Next Article in Journal
Influence of Ethanol on the Acid-Induced Flocculation of Casein Micelles
Previous Article in Journal
An Evaluation of Nutritional and Therapeutic Factors Affecting Pre-Weaned Calf Health and Welfare, and Direct-Fed Microbials as a Potential Alternative for Promoting Performance—A Review
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
Journals
Dairy
Volume 3
Issue 3
10.3390/dairy3030046
dairy-logo
Submit to this Journal Review for this Journal Propose a Special Issue
► Article Menu

Article Menu

share Share announcement Help format_quote Cite question_answer Discuss in SciProfiles thumb_up
...
Endorse textsms
...
Comment
first_page
settings
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

Packaging Weight, Filling Ratio and Filling Efficiency of Yogurt and Relevant Packagings Depending on Commercial Packaging Design, Material, Packaging Type and Filling Quantity

by
Dejan Kostic
1,†,
Udo Hoffmann
1,
Siegfried Fürtauer
2,
Tanja Fell
2,
Cihat Yilmaz
1,
Dirk Burth
1 and
Sven Sängerlaub
1,2,*,†
1
Department of Building Services Engineering, Paper and Packaging Technology and Print and Media Technology, Munich University of Applied Sciences HM, Lothstraße 38, 80335 Munich, Germany
2
Fraunhofer Institute for Process Engineering and Packaging IVV, Giggenhauser Straße 35, 85354 Freising, Germany
*
Author to whom correspondence should be addressed.
†
These authors contributed equally to this work.
Dairy 2022, 3(3), 668-692; https://doi.org/10.3390/dairy3030046
Submission received: 16 May 2022 / Revised: 12 August 2022 / Accepted: 5 September 2022 / Published: 16 September 2022
Browse Figures
Review Reports Versions Notes

Abstract

:
Yogurt is a diverse dairy product category. It is available in different packaging designs made of different materials. To identify potential for improvement for these packagings, a better understanding about used materials and packaging efficiencies is necessary. For this study, 150 dairy products and some yogurt relevant desserts were bought from various supermarkets, street markets and discounters in the Munich region (Germany) in spring 2022. Commercial types of packaging are cups, buckets, pouches, bottles, glass packagings and bricks. The filling ratio of most packagings is above 70%, the rest of the volume is headspace. Poly(1-methylethylene) (PP) and poly(1-phenylethene) (PS) dominate as main materials for the different types of packaging. For bottle packagings, poly(ethylene terephthalate) (PET) and polyethene high-density (PE-HD) are used. Interestingly, poly(lactic acid) (PLA) is not found. Closures (caps) are responsible for 5 to 30% of the total packaging weight. Typical filling efficiencies are 20 to 40 g food product packaged in one gram of packaging material. For glass packagings, the values are 1.5 to 2 g food product packaged in one gram of packaging material. Therefore, plastic packaging results in an at least ten-times lower packaging use per unit of food, at single use packagings. With increasing product weights, we observe a tendency towards higher packaging efficiencies. By using paper/carton wrapping at cups, plastic use is reduced for the whole packaging.

1. Introduction

1.1. Relevance of Packaging for the Environment

Food packaging is mandatory to enable handling, transport and storage of food. Food packagings inform consumers about necessary information (food type, ingredients, nutritional value, shelf-life etc.). They fulfil marketing needs, and furthermore, packaging prevents food from contamination and spoilage, thereby saving resources during the whole life cycle, particularly resources used for food production [1,2,3].
Apparently, many food packaging materials exhibit several ecological drawbacks, e.g., hindered effective separation and recycling, and non-biodegradability when leaked into the environment. As a countermeasure, new packaging materials such as poly(lactic acid) (PLA), other biobased polymers and composites have been developed [4,5,6,7]. PLA is biomass-derived and it is associated with greenhouse gas (GHG) emission savings [8]. However, on a worldwide scale, packaging material use is more than ever seen with concern or even critical [9,10], since packagings consume for example 40% of annual plastic production. Therefore, different regulations and policies have been initiated [11,12,13,14]. Programs such as the ‘Plastic Strategy for Europe’ [15] or the ‘German Packaging Waste Law’ [16] assign core responsibilities to food packaging manufacturers. To evaluate the environmental impact of food packaging, tools such as life-cycle assessment (LCA) have been developed [6,17,18,19,20,21,22,23,24].
As not much data are available in the scientific literature about efficiencies and types of packaging material used for certain food groups, this work will provide some valuable insights. It will support decision-makers in their choice for the most appropriate packaging.

1.2. Packaging Consumption in Germany

This study focuses on products available in Germany. Packaging material use in Germany was 227.5 kg/(year person) in 2018 and 2019 [25]. In Germany, in 2018 8.3 Mio. t paper and board, 3.4 Mio. t wood, 3.2 Mio. t plastic, 2.9 Mio. t glass, 0.51 Mio t. tinplate, 0.35 thin sheet and steel, 0.13 Mio. t aluminium and 0.03 Mio. t others such as cork, rubber, ceramic and textile were used [26,27]. The overall packaging use in Germany in 2019 was 18.91 Mio. t [28]. Approximately half of it was used by private consumers with an amount of 8.59 Mio. t [28].

1.3. Materials and Packaging Production Process for Yogurt Packaging

Yogurt is available on the market in different categories, diversifications and varieties such as dessert, drink-yogurt, Skyr, cream cheese and curd [29,30,31,32,33,34]. These address different consumer segments, such as the ‘the green packaging segment’, the ‘price sensitive’, ‘brand loyal[s]’ and ‘convenience seeking’ [35]. It is typically cold stored at temperatures around 4–5 °C [33,34]. It is eaten by spoon, or the viscosity is so low that it is drunk directly, e.g., as drink-yogurt. Some drink yogurt specialties contain menthol as aroma substance that migrates into the PET-packaging material (flavour-scalping) [36,37]. In Germany 673.800 t yogurt were produced in 2020 [38]. Yogurt is sold in different types of packaging: Cups, jars, bottles, pouches and in bigger quantities in canisters [32,39]. Often plastic packaging is used because ‘people much appreciate and routinely use plastic’ [40].
Cups are made of poly(1-methylethylene) (PP) [41] known as ‘polypropylene’; poly(1-phenylethene) (PS) [41,42] known as polystyrene; poly(ethylene terephthalate) (PET) and PLA [43,44,45,46] by injection moulding (PP) [47,48,49] or thermoforming (PP, PS, PET, PLA) [49,50,51,52,53,54,55,56,57,58]. Thermoforming is often supported by pre-blowing and pre-suction [59]. A part of the PET is recycled (rPET). Canisters are made by injection moulding. Cups are closed with aluminium foil, paper laminates or a plastic film. Some cups are wrapped by a paper or carton sleeve. Plastics often contain additives such as pigments [60]. It is worth to mention that PS is discussed in the literature due to possible migration of styrene into food products [42,61,62,63,64,65,66] besides other substances that can migrate [66].
Jars and other glass packagings are made of glass with a metal closure containing a plastic sealing compound. Glass jars are either for single-use or multi-use.
Bottles are made by two processes. When injection-blow-moulding is applied, first a preform is produced by injection moulding and then blown [49,67]. For this process, PET [68,69,70], rPET [71,72,73,74] or PS is used. PET-bottles for oxygen sensitive beverages can contain oxygen scavengers [75,76,77]. However, their use is not obvious by visual inspection of PET-bottles. The other process is extrusion blow moulding [49,78]. The main polymer used there is polyethene high-density (PE-HD) [79,80]. Bottles are routinely wrapped by shrink sleeves made of oriented plastic film.
Pouches contain a spout. The pouch itself is a laminate made by co-extrusion and lamination. The spout is made by injection moulding.
Bricks are made of beverage carton. Such packagings and materials are known from beverage packagings and from milk packagings. These are multilayer materials made of carton that is extrusion coated with polymer layers.
Packagings are decorated by direct printing, labelling with printed paper or plastic labels or in-mould labels [81]. For in-mould labelling, the label is inserted into the mould before forming and it fuses with the plastic cup [82]. Paper/carton and shrink sleeves for the cups are printed.
In Figure 1, typical packagings for yogurt are shown. A food bundle of yogurt cups is also depicted. These are preferred by some consumers and provide advantages in marketing [83,84].

1.4. Packaging Efficiencies

It is generally expected that smaller packagings have a poorer packaging efficiency (ratio of the packaged food weight/packaging weight) than larger packagings [85]. These relationships have scarcely been investigated systematically. One described finding was that an increasing bottle size correlates with a better packaging efficiency [86]. However, at further increasing bottle sizes, the packaging efficiency starts to decrease. Another finding was that packaging efficiencies improved in past decades [87].

1.5. Intention of This Study and Hypotheses

Packaging materials are highly discussed in public for their environmental impact. However, not much data are published about packaging efficiencies that can be found at real packagings on the market. Such information is of value for decisions how to choose certain packaging materials, different types of packaging and sizes, for better sustainability. Lower amounts of used packaging material lead to a better scoring concerning sustainability of the packaging material [88].
We chose yogurt for our study because many different products in different types of packaging and materials are found on the market.
Our hypotheses for this study were: (1) With increasing filling quantity, the packaging efficiency improves. (2) Glass packagings are more heavy than plastic packagings at the same filling quantity. (3) Cups made by injection moulding are less efficient compared to cups made by thermoforming. Thermoforming allows thinner materials and therefore more efficient packaging materials. (4) Cups made by thermoforming with fibre-based sleeves require less plastic compared to pure plastic cups. The paper/carton sleeves stabilise the plastic cups. Therefore, these can be made thinner.

2. Materials and Methods

2.1. Sample Acquisition

Samples were bought in January 2022 in the Munich area from German supermarkets (ALDI, LIDL, EDEKA, Netto, Kaufland, Neckarsulm, Germany), food chains (Yormas, Hofpfisterei, Germany) and small bakeries for yogurt to be eaten as snack. Few cups were bought in 2021, two in 2020 and one in 2018. In addition, some dessert and yogurt muesli food preparations as well as a soya-drink and a coconut-drink were included because these foods are packaged in yogurt relevant packagings.

2.2. Sample Processing

The packagings were fully emptied and cleaned with water and then dried overnight at 23 °C and circa 50% RH. Product information was noted from the receipt, ingredient list and before-date printing: product name, brand, shop, product weight, costs, best-before-date and date of buying.

2.3. Packaging Classification

The products were classified for the analysis and information was taken as follows.
  • Category: yogurt, dessert, drink yogurt, Skyr, cream cheese, curd, drink, yogurt alternative such as soya-drink or coconut-drink;
  • Packaging: Cup, bottle, glass jar and other glass packaging, bucket, pouch, brick made of beverage carton;
  • Materials: PP, PS, PE-HD, PET, rPET, paper laminate, glass single-use and multi-use
  • Lid material: aluminium, PP, PET, metal, paper laminate, PE-HD;
  • Decoration and decoration material: direct printing, plastic label, paper label, shrink sleeve, carton sleeve, secondary packaging;
  • Label category: in-mould label, carton-plastic combination;
  • Secondary packaging material: carton, plastic, plastic and aluminium lid, lid made of PET- or PP-film;
  • Secondary packaging: sleeve, lid, top-up, separate cup (e.g., for honey);
  • Production method: thermoforming, injection moulding, film extrusion, injection-blow-moulding, extrusion-blow moulding, extrusion coating, lamination, glass forming;
  • Shape: round, cornered, pouch;
  • Optical properties: white, transparent, brown, multi-colour;
  • Board type: FSC-mix, primary fibre, pulp, secondary fibre;
  • Marketing aspects: health claims (‘Actimel’), surrogate product, Ayran, fruit yogurt for children, Greek yogurt, yogurt with corner, yogurt with foot-segment at packaging (‘Zott’), yogurt with top-up, kefir, ‘Müllermilch’, curd, ‘Quetschies’ (yogurt in pouch), Skyr, street-food to go, drink yogurt;
  • Disposal note: all disposal notes, post-consumer recycling system, green dot, carton sleeve to be separated from cup, deposit information, no information about disposal.
Following information was not found on all packagings, but taken if available.
  • Company of cup production;
  • Recycling advice, remarks, certificates;
  • Printing techniques;
  • Light transmission (visual evaluation);
  • Pressure resistance (haptically evaluation).

2.4. Measuring of Weights

The measurements were carried out with an analytical balance (Sartorius, Germany, model BP 221 S, with a weighing range of 220 g and accuracy of 0.1 mg). For heavy glasses and the determination of the rim full volume (packaging totally filled to the edge), another balance was used (precision balance from Kern & Sohn GmbH, Germany, model KERN 572, with a weighing range of 8100 g and accuracy of 0.1 g).
Measured properties were:
  • Cup weight without label;
  • Cup weight with fixed label (with IML or paper label);
  • Lid weight, label weight;
  • Outer packaging weight; and
  • The maximum rim full volume of the container.
At bundles, the total packaging weight per packaging unit was calculated by summation of the total packaging weights for the entire product and division by the number of cups or number of packaging units.
To determine the rim full volume, the empty packaging was placed on the scale and the scale was zeroed. Then tap water was filled in, using a measuring beaker until the packaging was filled to the top rim (maximum filling amount before overflow) and the measured weight of the water was noted. The deviation that occurred due to surface tension during filling was marginal and was neglected if, after visual inspection, the measurement was legitimized by looking at it from the side and the water surface is flush with the beaker. The used tap water with a temperature of around 20 °C was assumed to have a density of 1 g/cm3. Therefore, the measured weight was equal to the volume and the rim full volume can be expressed in the units mL or in g. Consequently, the ratio of rim full volume or weight/package weight has the unit mL/g or g/g. The total volume of the food product at bundles was the rim full volume of a unit, multiplied with the total number of units.
The most important parameter of our evaluation is the ratio of the rim full volume or weight (maximum filling volume up to the edge of the packaging) in mL or g to the packaging weight in g. The ratio is the same for a packaging unit and the total food product. The ratio of the food weight to packaging weight was not always meaningful due to the different densities of the food products.
The plastic type of cups, whose plastic type was not declared on the cup base or outer packaging, can be determined by means of density differences in the float/sink method and distinguished between polyolefins/PP and PS/PET [89]. The density of PP is between 0.90 and 0.91 [90,91], PS 1.05, PLA 1.24 g/cm3 [92], and PET 1.37 g/cm3 [93]. An additional method is infrared identification and separation [94]. However, these methods of characterization were not applied in this study.

3. Results and Discussion

3.1. Product Categories, Packaging Means, Bundles, Filling Weight Distributions, Filling Ratios, Materials and Processes for Packaging Production

3.1.1. Product Categories

In Figure 2 the analysed product categories are shown. Information was taken from the labels. Every product category represents one type of packaging. 58% of all samples were (spoonable) yogurt, 10% drink yogurt; 18% Skyr, fresh cheese, curd, yogurt surrogates (plant yogurt) and drinks (e.g., flavoured milk) and 14% dessert such as ‘Creme Brulee’, ‘Mango Passione’ dessert and similar. Drinks and desserts were included in this study when these products were packaged in packaging means that could be used also for yogurt. Some of the desserts were packaged in glass packagings, which allowed correlations with such kind of packagings.

3.1.2. Packaging Means

In Figure 3 the amount of packagings in each packaging mean classification are shown. The depicted packagings are all different. However, in shops the same packaging mean can be used for different flavours of yogurt.
The most often found packaging means were cups. The reason is the established production method thermoforming (see Section 3.1.6) and existing and well-developed (aseptic) filling lines at manufacturers. It is worth to mention that the number of packagings in each category does not represent how much volume is sold on the market. Several packagings are positioned in niche markets with low selling quantities. Surprising was that cups made of deep drawn or pulled fibre material or coated fibre material were not found, even though such materials have been subject of intensive research [95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117]. Only one packaging was found (not depicted) that consisted of formed, coated and sealed paper. (However, it was not deep drawn or pulled fibre material.)
Interestingly, only a small part of the analysed packagings were made of glass (n = 13), despite its advantages. Glass packagings are perceived as more pleasant and sustainable by consumers [118]. Saint-Eve et al. found better aroma preservation of flavoured stirred yogurts in glass packaging, compared to PS- and PP-based packaging [119], explained by higher barrier in case of glass packagings. Restricted use of glass is probably influenced by higher weight, higher packaging price, higher logistic costs due to packaging weight and volume (often not stackable) and safety concerns (glass breakage) at production sites.
Pictures of packaging means are shown in the Supplementary Materials Figure S1.

3.1.3. Bundles

In Figure 4, the amount of single packaging units per bundle is shown. Most packagings were sold as single packaging (124), 17 in bundles of 4 smaller units and the rest in bundles up to 2, 6, 8 and 12 smaller units. Bundles often require a secondary packaging. Bundles are perceived differently by consumers compared to single packagings [83], which is relevant for marketing [120].

3.1.4. Filling Weight Distribution

In Table 1 the filling weights in g product per unit primary packaging are shown. The filling weights are widely distributed between 50 g and 1000 g. Filling weights of 150 g occur most often, followed by 500 g and 200 g for single packagings. For buckets, only one filling weight (1000 g) was observed.

3.1.5. Filling Ratio

A packaging is considered as a ‘deceptive packaging’ (in German ’Mogelpackung’) when it contains more than 30 vol.-% of headspace [121,122]. In Figure 5 the filling ratio is shown. It is calculated from the product weight in the packaging and the rim full weight. For simplification, the density of the food was assumed as 1 g/cm3.
Values for pouches and bricks underestimate the filling ratio. These packagings are flexible and buckle when filled with water to determine the rim full weight. Therefore, real filling ratios might have higher values there when filled with real products.
Low filling ratios of cups are associated to foamed products. At foamed products such as mousse and whipped cream the density is lower than 1 g/cm3.
Cups, buckets, bottles and glass packagings always have a head space volume. Therefore, filling ratios are always below one. Considering the previous mentioned restrictions for the interpretation (plastic) bottles have the best filling ratio with a mean value of 0.95, followed by bricks with a measured mean value of 0.93. For cups and glass packagings the filling ratios vary most, which is attributed to the variations in the packaging design. Flat packagings have a worse filling ratio. Overall, the filling ratio was above 70 wt.-% or vol.-% in almost all cases. Therefore, most of the analysed packagings cannot be considered as deceptive packagings.

3.1.6. Materials and Processes for Packaging Material Production

The dominating materials for cups (Figure 6) were PP (60%), followed by PS (32%). PET and rPET represented around 4% each. Only one sample was made of coated fibre material. Four samples could not be assigned to a certain material. This finding is interesting, since PLA was hardly or not at all present on the market, even though it has been a subject of research and development for packaging for several decades [123,124,125,126,127,128,129,130,131,132,133,134]. A possible explanation is that the bioplastic PLA is not seen by consumers as more sustainable as conventional plastics. The willingness to pay more for packagings perceived by consumers as non-sustainable is restricted [135]. PLA can be assumed to be a more expensive polymer. Moreover, recycling of PLA is not established (yet), even though, current regulations require higher recycling rates.
The minor part of cups (n = 13) was produced by injection moulding. These were made of PP. The rest of the samples were produced by thermoforming (n = 95). The fibre-based cup was made by lamination.
Dominating closures were aluminium lids with 86 % (n = 94). Moreover, PET (n = 6), rPET (n = 2), PP (n = 2) and cellulosic fibre materials (coated and sealed paper) were used (n = 1). In four samples, the material was unclear.
PP- and PET-packagings are well recyclable if they are transparent and clear [136,137,138,139,140]. For PP-recyclates, a commercial market exists [141], as well as for rPET. For PS a solvent-based recycling process is relevant [136,142]. Post-consumer recyclates often contain odour active substances [143,144,145,146,147,148]. A source for unpleasant odours is the filled good. Such must be considered when foods with volatile aroma components are packaged that migrate into the plastic material.
In Figure 7 the decoration of the cups (excluding lids) is shown.
Slightly less than half of the packagings had decoration that can be removed by consumers (shrink sleeves made of plastic film, thickness 40 to 50 µm; paper/carton wrappings with a thickness of 250–540 µm and paper wrappings at bundles) or had no decoration. Such packagings are considered as more recycling friendly if consumers remove the shrink sleeve and wrappings and dispose them separately. No decoration was observed at packagings sold at street shops for direct eating. Printing inks from direct print are potentially problematic for recycling since it required additional efforts to remove them.
One reason for different decoration materials (paper and plastic) is that different packaging materials are perceived differently concerning its sustainability and these may influence the perceived taste and quality [149]. Furthermore, decoration is relevant because printed claims on the decoration can influence ‘perceived taste’ and the ‘amount consumers were willing to pay for the product’ [150]. Decoration and its design is therefore a part of the marketing strategy [151,152]. Wang et al. found for yogurt packagings, that ‘consumers presented the highest preference for yogurt packaging shape, followed by graphics, label text and packaging colour’ [153].
All analysed buckets (n = 5) were made of PP by injection moulding. The lids were also made of PP. Decoration were in-mould labels.
All analysed pouches (n = 5) were multilayer films made of unknown plastic types. Possible production methods were film extrusion and lamination. Decorations were directly printed on the films. The closures were made of plastics either. In one case, the secondary packaging was made of cardboard.
From the analysed bottles (n = 14), ten were made of PET via injection blow moulding. Two bottles were made of PS, one by injection moulding and one by extrusion blow moulding, two bottles were made of PE-HD by extrusion blow moulding. A total of 12 of the 14 bottles had a printed plastic shrink sleeve, one a paper label and one a plastic label. In case of bundles, a carton sleeve was used. The closures were made of PE-HD closures made by injection moulding (n = 10), PE (n = 1) and aluminium lids (n = 3).
Glass packagings (n = 13) were for multi-use (n = 4) and single use (n = 9). The closures were lids of metal (n = 8) presumably coated metal sheets, aluminium (n = 2) and plastic (n = 3). Glass packagings had a printed paper label (n = 7), a printed paper/carton wrapping (n = 4), a printed wrapping for a bundle (n = 1) or a printed plastic label (n = 1).
Bricks (n = 4) were made of directly printed beverage carton made by extrusion coating. The closures were made of PE-HD (n = 4).
The cardboard types of the paper/carton wrappings and folding boxes are based on 40% FSC MIX and have different compositions of primary and secondary fibres (Figure 8). The other part is 37% secondary fibres and 24% primary fibres. In total, 54 cartons were considered.
For recycling, the appearance is an important aspect, as sorting works via various scanning systems using near infrared radiation (NIR) [94,154,155,156,157,158,159,160,161,162,163,164,165,166]. Apart from black, colouring is negligible in sorting, but it does influence the colour results of the recyclates and it reduces their value. The appearance of the analysed packaging (packaging body, not labels; Figure 9) is mainly white (66%) or transparent (27%). A few products are coloured (4%) or brown (3%).
The colour and transparency is also of relevance because light-induced quality changes can occur [167,168]. These are explained by oxidation and were observed also at other dairy products [169,170,171].

3.2. Closure to Packaging Weight Ratio

An interesting property is the ratio between closure and packaging. In Figure 10, the closure weights are compared to the weights of the packaging, including lid, possible shrink sleeve, and possible shrink labels. In a simplified manner, a straight-line equation with origin 0 was applied. As expected, the closure weight positively correlates with the packaging weight.
In Figure 11, the ratio of closure weight to the packaging weight is depicted as box plot. The packaging weight includes sleeves (at bundles, weight divided by single packagings) and shrink labels. For heavy packagings, the closure has the smallest share of the overall packaging weight. For pouches, which are thin and light materials, the closure takes a bigger part of the overall weight, as expected.

3.3. Packaging Efficiencies at All Different Types of Packaging

Packaging Efficiencies Related to Food Product Weight

In Figure 12 the food product weights (packaged food) versus the packaging weights are shown. The food product weight was taken from the packaging declaration, e.g., labels or prints (the results for the body without closure, but with in-mould label, because it could not be removed and with all packaging parts used for a single packaging, are depicted in Supplementary Materials, Figure S2). In case of bundles wrappings are distributed evenly to each packaging. For representation, a linear correlation is included.
By the results is shown that the packaging weight and the product weight have no strong correlation. Because of the different packaging means used, different packaging weights can be found in one packaging category. (Also, the density of product can cause different results even for the same filling volume. This was not further examined). This data was used for the calculation of the packaging efficiencies (see next paragraph).
The food product weights were divided by the packaging weights (Figure 13) to be able to compare packaging material use efficiency. Up to almost 40 g food could be packaged in one gram of packaging material. Most packagings enable to package 15 to 25 g of food in one gram of packaging material. The values scatter highly especially for cups, which is caused by different foods packaged and different packaging means used. Best efficiencies are observed at some cups, bricks, buckets, and pouches. Glass packagings had the lowest efficiencies due to the high weights required (1.6 g to 1.7 g product per 1 g of product). Glass has a high density with 2.5 g/cm3 (soda-lime glass) [172,173] and it is a brittle material. Therefore, the wall thickness must be higher compared to the other types of packaging. When the values are calculated for the packaging bodies only (separatable elements excluded), the packaging efficiencies become even slightly better (see Supplementary Materials, Figure S2). Such values are interesting because separatable elements can be substituted by well recyclable fibre-based materials.
The ‘GVM Gesellschaft für Verpackungsmarktforschung mbH’ showed in a study from May 2022 that yogurt in plastic cups had a packaging efficacy of 41.7 g yogurt packaged in one gram of packaging material valid for the year 2020 [87]. For the year 1998, this value was worse with 35.6 g yogurt packaged in one g of packaging material. For glass packagings, they reported 1.52 g yogurt packaged in one gram of packaging material. Even though, it is not clear if these efficiencies were calculated for the packaging materials with or without labels and closures, these values are the range of the results of our study.
Klooster et al. showed for glass bottles a ratio of similar values of about 2 g beverage per 1 g of glass packaging [174]. Another study found a packaging use of all packaging at yogurt between 10 and 20 g of food packaged with 1 g packaging material [175]. For beverages (not in glass bottles), a ratio of circa 25 to 35 g of packaging material use for 1 g of packaging was found [176]. The packaging efficiencies found in our study, for both cups and bottles, were therefore slightly better than that reported in the literature.
An important question is, if a higher filling quantity causes a better packaging material use efficiency. To analyse this correlation, the efficiency (filled food product weight/required packaging weight) is depicted as function of the product weight (Figure 14). Even though the results scatter highly for cups, bottles and bricks, it can be concluded that the packaging material use efficiency improved with higher weight of filled good. In Supplementary Materials Figure S2, the values referring only to the packaging bodies are shown. Results for this evaluation are similar.

3.4. Packaging Efficiencies of Cups

Cups can be differentiated by their types of packaging, applied polymers and production methods. Therefore, this packaging type was investigated in more detail. Because food products of different densities were packaged in cups, the results in this chapter are correlated to the rim full weight of water of the packagings. Packaging consisting of separate elements such as ‘top-ups’ filled with product were not considered in this evaluation.
In Figure 15, rim full weights (filled packaging to edge with water) of water divided by the packaging weights are shown. In Figure 15a, the ratio of the rim full weight divided by the overall packaging weight (including the lid and wrapping) is shown. In Figure 15b, the ratio of the rim full weight divided by the cup body only is shown. This allows to evaluate if a paper/carton wrapping causes less plastic use. As expected in Figure 15a, the efficiencies are lower than in Figure 15b because all parts of the packaging are counted.
Direct printing resulted in the best efficiencies when all packaging components are included (Figure 15a). For direct printed thermoformed cups, PS as used polymer was slightly more efficient than PP.
Injection moulding as well as wrappings and shrink sleeves causes less efficient packaging and more packaging material use (Figure 15a).
However, if the rim full weight is divided only by the weight of the cup body (excluding the paper/carton wrapping and lid), the cups made by thermoforming with paper/carton wrapping yield the best results. That is explained by the properties of the paper/carton wrapping. It provides stiffness and higher mechanical strength. Therefore, the plastic cup wall thickness can be reduced. The plastic use is significantly reduced (Figure 15b). That is an important result since many companies try to reduce their plastic use. However, as discussed before, when the paper/carton wrap weight is considered for the calculation of the packaging efficiency (Figure 15a), the packaging material use efficiency is reduced. Hereby, it is worth to consider that the paper/carton wrapping can be separately disposed into the paper recycling stream. Disposal advice was found at almost all such packagings (see Section 3.5). At cups with paper/carton wrapping for 1 g of cup-material (plastic), circa 0.9 g of wrapping-material (paper) and 0.1 g of materials for the closures were used. A shrink sleeve at PP did increase packaging material use efficiency. However, not as much as paper/carton wrappings.
Similar results as in this study for yogurt cups with paper wraps were found before by Aggarwal et al. with a slightly higher use of PP compared to PS for cups [128]. In his study it is reported that 46 g and 43 g of yogurt are packages for every one gram PP and PS cup material (only body, without paper wrap). PLA resulted in 63 g yogurt for one gram of PLA. The paper/carton sleeve thickness presented in Aggarwal’s study was 153 µm and 393 µm. In our study we found carton sleeve thicknesses of 250 to 520 µm.

3.5. Disposal Advice on Packagings

Interestingly, most (54 %) of the packagings had no exposed advice for recycling. The other packagings had various recycling advice (Figure 16).
The packagings without advice for recycling were decorated by an in-mould label (n = 11), a label (n = 12), direct print (n = 13) and a shrink sleeve (n = 3). We assume that it is expected that such packagings are disposed by consumers to the post-consumer packaging collection systems for further recycling. Advice for separation would in this case only be of value for the lid. The rest had no decorative label, e.g., as street food.
Only one sample with paper/carton wrapping had no disposal advice. Disposal advice for packagings with paper/carton wrappings are important since all components (cup, lid, wrapping) must be separated. For single cups with paper/carton wrapping, the paper and the plastic body of the cup are glued with few glue-points. For recycling it is important that the paper wrapping is separated from the plastic body and of the cup, as well as that lid is separated. The paper should be disposed in the paper stream.
More than half of these packagings had disposal advice for all parts (n = 14), the rest for the paper wrapping only (n = 9) or no advice at all (n = 1). Some pictures of disposal advice can be found in the Supplementary Materials, Figure S3.

3.6. Correlation between Product Cost and Packaging Use

An interesting aspect is the correlation between the food cost and the amount of packaging material use per food filling weight. In Figure 17 the packaging efficiency (food product weight versus used packaging weight) is correlated with the product cost. The higher the cost of the food the lower is the packaging material efficiency. More packaging material is used to package the same amount of food. An explanation is that more expensive foods are packaged in smaller units with less food weight per single packaging.

4. Conclusions

Our study provides indications that a higher filling amount results in a better packaging material use efficiency. In addition, our results show that a paper/carton wrapping reduces overall required plastic use. However, it also reduces the packaging efficiency of the whole packaging when the paper/carton wrapping is included. Injection moulding causes more material use compared to thermoforming and it was therefore slightly less efficient in terms of plastic usage. At least ten-times higher packaging weight per packaged food unit was seen when glass is used. Overall, our hypotheses were proved by the study.
Alternative packaging materials made of PLA, pulled or deep-drawn fibre materials (paper, carton, paperboard) or other biopolymers were not found. This result is interesting because much research has been done on these materials.
Our results are a valuable input for the calculation of life cycle assessments, in which packaging weights play an important role. Recycled plastics, here only rPET, for yogurt packagings was identified only at four products in our survey. Interesting for future investigations is a comparison of our results with results from other countries, since product types and materials might differ.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/dairy3030046/s1, Figure S1: Pictures of samples, Figure S2: Packaging efficiencies related to product weight, Figure S3: Disposal advice on packagings, Table S1: Raw data.

Author Contributions

Conceptualisation, S.S. and D.K.; methodology, S.S. and D.K.; validation, D.K., S.S., S.F., U.H. and T.F.; formal analysis, D.K., C.Y. and S.S.; investigation, D.K.; resources, S.S. and D.K.; data curation, D.K.; writing—original draft preparation, S.S. and D.K.; writing—review and editing, S.S., S.F., T.F., D.B. and D.K.; visualisation, S.S. and D.K.; supervision, S.S., U.H.; project administration, S.S. All authors have read and agreed to the published version of the manuscript.

Funding

This work was financially supported by the Munich University of Applied Sciences HM and the German Research Foundation (DFG) through the “Open Access Publishing” program.

Institutional Review Board Statement

Ethical review and approval were waived for this study due to the fact, that all products have been eaten and not wasted.

Informed Consent Statement

Not applicable.

Data Availability Statement

Data are available upon request.

Acknowledgments

The authors would like to thank everyone who helped to buy and eat all dairy products used for measurements.

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. Lindh, H.; Williams, H.; Olsson, A.; Wikström, F. Elucidating the indirect contributions of packaging to sustainable development: A terminology of packaging functions and features. Packag. Technol. Sci. 2016, 29, 225–246. [Google Scholar] [CrossRef]
  2. Welle, F. Food packaging. Chem. Unserer Zeit 2007, 41, 96–106. [Google Scholar] [CrossRef]
  3. Rasul, S.F.; Noori, R.J.; Ali, K.M.; Khdhir, R.B.; Ahmed, S.R.; Qadir, A.M. Roles of different packaging materials on the quality and shelf life of yogurt. Food Sci. Technol. 2022, 42. [Google Scholar] [CrossRef]
  4. Brody, A.L. Sustainability and alternatives to today’s food packaging. Food Technol. 2006, 60, 72–74. [Google Scholar]
  5. Reichert, C.L.; Bugnicourt, E.; Coltelli, M.-B.; Cinelli, P.; Lazzeri, A.; Canesi, I.; Braca, F.; Martínez, B.M.; Alonso, R.; Agostinis, L.; et al. Bio-based packaging: Materials, modifications, industrial applications and sustainability. Polymers 2020, 12, 1558. [Google Scholar] [CrossRef] [PubMed]
  6. Aggarwal, A.; Schmid, M.; Patel, M.K.; Langowski, H.-C. Function-driven investigation of non-renewable energy use and greenhouse gas emissions for material selection in food packaging applications: Case study of yoghurt packaging. In Proceedings of the 27th CIRP Life Cycle Engineering Conference, LCE 2020, Grenoble, France, 13–15 May 2020; Brissaud, D., Zwolinski, P., Paris, H., Riel, A., Eds.; Elsevier: Amsterdam, The Netherlands, 2020; pp. 728–733, ISBN 22128271. [Google Scholar]
  7. Shah, M.A.; Schmid, M.; Aggarwal, A.; Wani, A.A. Testing and quality assurance of bioplastics. In Food Packaging Materials: Testing & Quality Assurance; CRC Press: Boca Raton, FL, USA, 2017; pp. 201–231. ISBN 9781466559950. [Google Scholar]
  8. Philp, J.C.; Bartsev, A.; Ritchie, R.J.; Baucher, M.-A.; Guy, K. Bioplastics science from a policy vantage point. New Biotechnol. 2013, 30, 635–646. [Google Scholar] [CrossRef] [PubMed]
  9. Verghese, K.; Lewis, H.; Fitzpatrick, L. Packaging for Sustainability; Springer: London, UK, 2012; ISBN 9780857299888. [Google Scholar]
  10. Licciardello, F. Packaging, blessing in disguise. Review on its diverse contribution to food sustainability. Trends Food Sci. Technol. 2017, 65, 32–39. [Google Scholar] [CrossRef]
  11. Sinclair, A.J.; Fenton, R.W. Stewardship for packaging and packaging waste: Key policy elements for sustainability. Can. Public Admin. 1997, 40, 123–148. [Google Scholar] [CrossRef]
  12. Bailey, I.G. Competition, sustainability and packaging policy in the UK. J. Environ. Plan. Manag. 1999, 42, 83–102. [Google Scholar] [CrossRef]
  13. Bailey, I. Principles, policies and practice: Evaluating the environmental sustainability of Britain’s packaging regulations. Sustain. Dev. 2000, 8, 51–64. [Google Scholar] [CrossRef]
  14. Lewis, H. Defining product stewardship and sustainability in the Australian packaging industry. Environ. Sci. Policy 2005, 8, 45–55. [Google Scholar] [CrossRef]
  15. European Union. Communication from the Commission to the European Parliament, the Council, the European Economic and Social Committee and the Committee of the Regions a European Strategy for Plastics in a Circular Economy, Document 52018DC0028; COM/2018/028 Final; European Union: Brussels, Belgium, 2018. [Google Scholar]
  16. Deutscher Bundestag. Gesetz Über das Inverkehrbringen, die Rücknahme und die Hochwertige Verwertung von Verpackungen: (VerpackG); Bundesgesetzblatt: Köln, Germany, 2017; pp. 2234–2261.
  17. Lewis, H.; Verghese, K.; Fitzpatrick, L. Evaluating the sustainability impacts of packaging: The plastic carry bag dilemma. Packag. Technol. Sci. 2010, 23, 145–160. [Google Scholar] [CrossRef]
  18. Wever, R.; Vogtländer, J. Eco-efficient value creation: An alternative perspective on packaging and sustainability. Packag. Technol. Sci. 2013, 26, 229–248. [Google Scholar] [CrossRef]
  19. Pauer, E.; Wohner, B.; Heinrich, V.; Tacker, M. Assessing the environmental sustainability of food packaging: An extended life cycle assessment including packaging-related food losses and waste and circularity assessment. Sustainability 2019, 11, 925. [Google Scholar] [CrossRef]
  20. Keller, J.; Scagnetti, C.; Albrecht, S. The Relevance of Recyclability for the Life Cycle Assessment of Packaging Based on Design for Life Cycle. Sustainability 2022, 14, 4076. [Google Scholar] [CrossRef]
  21. Dormer, A.; Finn, D.P.; Ward, P.; Cullen, J. Carbon footprint analysis in plastics manufacturing. J. Clean. Prod. 2013, 51, 133–141. [Google Scholar] [CrossRef]
  22. Suwanmanee, U.; Varabuntoonvit, V.; Chaiwutthinan, P.; Tajan, M.; Mungcharoen, T.; Leejarkpai, T. Life cycle assessment of single use thermoform boxes made from polystyrene (PS), polylactic acid, (PLA), and PLA/starch: Cradle to consumer gate. Int. J. Life Cycle Assess. 2013, 18, 401–417. [Google Scholar] [CrossRef]
  23. Keoleian, G.A.; Phipps, A.W.; Dritz, T.; Brachfeld, D. Life Cycle Environmental Performance and Improvement of a Yogurt Product Delivery System. Packag. Technol. Sci. 2004, 17, 85–103. [Google Scholar] [CrossRef]
  24. Detzel, A.; Bender, C.; Ettinger, T.; Schmidt, A.; Kauertz, B. Rahmendokument zu den Übersichtsökobilanzen im Projekt Innoredux, Heidelberg. 2021. Available online: https://www.plastik-reduzieren.de/ (accessed on 1 May 2022).
  25. Statista. Verpackungen: Verbrauch pro Person in Deutschland bis 2019. Available online: https://de.statista.com/statistik/daten/studie/914344/umfrage/verpackungen-verbrauch-pro-person-in-deutschland/ (accessed on 1 March 2022).
  26. Statista. Verbrauch von Verpackungen nach Materialart in Deutschland im Jahr 2018 (in 1.000 Tonnen). Available online: https://de.statista.com/statistik/daten/studie/914285/umfrage/verpackungen-verbrauch-in-deutschland/ (accessed on 1 March 2022).
  27. BMUV. Verpackungen gesamt Verbrauch, Verwertung, Quoten 1991 bis 2018 (in Kilotonnen) in der Bundesrepublik Deutschland. 2020. Available online: https://www.bmuv.de/fileadmin/Daten_BMU/Download_PDF/Abfallwirtschaft/datentabelle_verbrauch_verwertung_quoten_bf.pdf (accessed on 1 April 2022).
  28. Burger, A.; Cayé, N.; Jaegermann, C.; Schüler, K. Texte 148/2021, Aufkommen und Verwertung von Verpackungsabfällen in Deutschland im Jahr 2019, Abschlussbericht, 2021. Available online: https://www.umweltbundesamt.de/sites/default/files/medien/1410/publikationen/2021-11-23_texte_148-2021_aufkommen-verwertung-verpackungsabfaelle-deutschland-2019_bf.pdf (accessed on 1 March 2022).
  29. Chandan, R.C.; Kilara, A. Manufacturing Yogurt and Fermented Milks, 2nd ed.; John Wiley and Sons: Hoboken, NJ, USA, 2013; ISBN 9781119967088. [Google Scholar]
  30. Verriet, J.; Leroy, F. Yogurt’s flexible image during its rise in popularity in post-war Belgium. Appetite 2017, 108, 132–140. [Google Scholar] [CrossRef]
  31. Wierzejska, R.; Siuba-Strzelińska, M.; Jarosz, M. Evaluation of dairy products available on the Polish market in the context of nutrient profiles. Clear arguments for reformulation of foodstuffs. Rocz. Panstw. Zakl. Hig. 2017, 68, 43–50. [Google Scholar]
  32. Aryana, K.J.; Olson, D.W. A 100-Year Review: Yogurt and other cultured dairy products. J. Dairy Sci. 2017, 100, 9987–10013. [Google Scholar] [CrossRef] [PubMed]
  33. Corrieu, G.; Béal, C. Yogurt: The product and its manufacture. In Encyclopedia of Food and Health; Caballero, B., Finglas, P.M., Toldrá, F., Eds.; Academic Press: Oxford, UK, 2016; pp. 617–624. ISBN 978-0-12-384953-3. [Google Scholar]
  34. Behare, P.; Kumar, H.; Mandal, S. Yogurt: Yogurt based products. In Encyclopedia of Food and Health; Caballero, B., Finglas, P.M., Toldrá, F., Eds.; Academic Press: Oxford, UK, 2016; pp. 625–631. ISBN 978-0-12-384953-3. [Google Scholar]
  35. Rokka, J.; Uusitalo, L. Preference for green packaging in consumer product choices—Do consumers care? Int. J. Consum. Stud. 2008, 32, 516–525. [Google Scholar] [CrossRef]
  36. Farhoodi, M.; Emam-Djomeh, Z.; Oromiehie, A.; Ehsani, M.R. Influence of menthol absorption on the mechanical properties of PET bottles. Iran. Polym. J. Eng. Ed. 2009, 18, 227–232. [Google Scholar]
  37. Farhoodi, M.; Emam-Djomeh, Z.; Falah, A.; Sabetghadam, S.; Nemati, M. Effect of menthol absorption by packaging material on the quality of yogurt drink during storage time. J. Agric. Sci. Technol. 2013, 15, 1373–1380. [Google Scholar]
  38. Ahrens, S. Produktion von Joghurt (ohne Zusätze) in Deutschland in den Jahren 2000 bis 2020. 2021. Available online: https://de.statista.com/statistik/daten/studie/239697/umfrage/herstellung-von-joghurterzeugnissen-in-deutschland/ (accessed on 1 May 2022).
  39. Wohner, B.; Schwarzinger, N.; Gürlich, U.; Heinrich, V.; Tacker, M. Technical emptiability of dairy product packaging and its environmental implications in Austria. PeerJ 2019, 2019, e7578. [Google Scholar] [CrossRef] [PubMed]
  40. Heidbreder, L.M.; Bablok, I.; Drews, S.; Menzel, C. Tackling the plastic problem: A review on perceptions, behaviors, and interventions. Sci. Total Environ. 2019, 668, 1077–1093. [Google Scholar] [CrossRef] [PubMed]
  41. Franz, R.; Welle, F. Recycling of post-consumer packaging materials into new food packaging applications—Critical review of the European approach and future perspectives. Sustainability 2022, 14, 824. [Google Scholar] [CrossRef]
  42. Guazzotti, V.; Hendrich, V.; Gruner, A.; Fiedler, D.; Störmer, A.; Welle, F. Migration of styrene in yogurt and dairy products packaged in polystyrene: Results from market samples. Foods 2022, 11, 2120. [Google Scholar] [CrossRef]
  43. Markevičiūtė, Z.; Varžinskas, V. Smart Material Choice: The Importance of Circular Design Strategy Applications for Bio-Based Food Packaging Preproduction and End-of-Life Life Cycle Stages. Sustainability 2022, 14, 6366. [Google Scholar] [CrossRef]
  44. Sirisinha, K.; Wirasate, S.; Sirisinha, C.; Wattanakrai, N. One-Pot Reactive Melt Recycling of PLA Post-Consumer Waste for the Production of Block Copolymer Nanocomposites of High Strength and Ductility. Polymers 2022, 14, 3642. [Google Scholar] [CrossRef]
  45. Jungbluth, N.; Keller, R.; Meili, C. Life cycle assessment of a detailed dairy processing model and recommendations for the allocation to single products. Int. J. Life Cycle Assess. 2018, 23, 1806–1813. [Google Scholar] [CrossRef]
  46. Weinkötz, P.; Schade, C. To each Yoghurt tub, its own polystyrene. Kunsts. Int. 2006, 96, 55–59. [Google Scholar]
  47. Bonten, C. Kunststofftechnik: Einführung und Grundlagen, 3rd ed.; Hanser: Munich, Germany, 2020; ISBN 9783446465381. [Google Scholar]
  48. Rosato, D.V.; Rosato, D.V.; Rosato, M.G. (Eds.) Injection Molding Handbook, 3rd ed.; Springer International Publishing: Cham, Switzerland, 2000; ISBN 9781461545972. [Google Scholar]
  49. Selke, S.E.M.; Culter, J.D. Plastics Packaging: Properties, Processing, Applications, and Regulations, 3rd ed.; Hanser Publishers: Munich, Germany, 2016; ISBN 9781569905463. [Google Scholar]
  50. Engelmann, S. Advanced Thermoforming: Methods, Machines and Materials, Applications and Automation; John Wiley & Sons: New York, NY, USA, 2012; ISBN 9781118207055. [Google Scholar]
  51. Schwarzmann, P. Thermoforming: A Practical Guide, 2nd ed.; Hanser Publishers: Cincinnati, OH, USA, 2019. [Google Scholar]
  52. Kayatz, F.; Schult, A.; Majschak, J.-P.; Liebmann, A. New developments in thermoforming. Kunsts. Int. 2017, 107, 24–26. [Google Scholar]
  53. Wagner, S.; Münsch, M.; Kayatz, F.; Majschak, J.-P.; Delgado, A. Modeling of the Compressed-Air Flow Impact for Thermoforming Simulations; Springer: Berlin/Heidelberg, Germany, 2018; ISBN 14397358. [Google Scholar]
  54. Wagner, S.; Kayatz, F.; Münsch, M.; Sanjon, C.W.; Hauptmann, M.; Delgado, A. Numerical modeling of forming air impact thermoforming. Int. J. Adv. Manuf. Technol. 2022, 120, 4917–4933. [Google Scholar] [CrossRef]
  55. Wagner, S.; Sheikhi, R.; Kayatz, F.; Münsch, M.; Hauptmann, M.; Delgado, A. Fluid–structure-interaction simulations of forming-air impact thermoforming. Polym. Eng. Sci. 2022, 62, 1294–1309. [Google Scholar] [CrossRef]
  56. Kuehne, G. Thermoforming. Kunsts Ger. Plast. 1981, 71, 28–29. [Google Scholar]
  57. Guo, C.; Guo, H. Progress in the Degradability of Biodegradable Film Materials for Packaging. Membranes 2022, 12, 500. [Google Scholar] [CrossRef]
  58. Sängerlaub, S.; Lehmann, E.; Müller, K.; Wani, A.A. Porosity, thickness distribution and water vapour sorption of thermoformed foamed PP films with dispersed sodium chloride for humidity regulation. Food Packag. Shelf Life 2020, 24, 100482. [Google Scholar] [CrossRef]
  59. Hopmann, C.; Michaeli, W. Einführung in die Kunststoffverarbeitung, 8th ed.; Hanser: Munich, Germany, 2017; ISBN 9783446453562. [Google Scholar]
  60. Singh, P.; Saengerlaub, S.; Wani, A.A.; Langowski, H.-C. Role of plastics additives for food packaging. Pigment Resin Technol. 2012, 41, 368–379. [Google Scholar] [CrossRef]
  61. Tawfik, M.S.; Huyghebaert, A. Polystyrene cups and containers: Styrene migration. Food Addit. Contam. 1998, 15, 592–599. [Google Scholar] [CrossRef]
  62. Vitrac, O.; Challe, B.; Leblanc, J.-C.; Feigenbaum, A. Contamination of packaged food by substances migrating from a direct-contact plastic layer: Assessment using a generic quantitative household scale methodology. Food Addit. Contam. 2007, 24, 75–94. [Google Scholar] [CrossRef] [PubMed]
  63. Vitrac, O.; Leblanc, J.-C. Consumer exposure to substances in plastic packaging. I. Assessment of the contribution of styrene from yogurt pots. Food Addit. Contam. 2007, 24, 194–215. [Google Scholar] [CrossRef] [PubMed]
  64. Pilevar, Z.; Bahrami, A.; Beikzadeh, S.; Hosseini, H.; Jafari, S.M. Migration of styrene monomer from polystyrene packaging materials into foods: Characterization and safety evaluation. Trends Food Sci. Technol. 2019, 91, 248–261. [Google Scholar] [CrossRef]
  65. Guazzotti, V.; Gruner, A.; Juric, M.; Hendrich, V.; Störmer, A.; Welle, F. Migration testing of GPPS and HIPS polymers: Swelling effect caused by food simulants compared to real foods. Molecules 2022, 27, 823. [Google Scholar] [CrossRef] [PubMed]
  66. Welle, F. Diffusion coefficients and activation energies of diffusion of organic molecules in polystyrene below and above glass transition temperature. Polymers 2021, 13, 1317. [Google Scholar] [CrossRef]
  67. Belcher, S.L. Practical Guide to Injection Blow Molding; CRC Press: Boca Raton, FL, USA, 2007; ISBN 9780429119262. [Google Scholar]
  68. Müller, K. Oxygen permeability of plastic bottles for oxygen sensitive beverages. Brew. Sci. 2007, 60, 74–83. [Google Scholar]
  69. Müller, K.; Welle, F. PET in beverage packaging. Kunsts Plast. Eur. 2005, 95, 120–125. [Google Scholar]
  70. Franz, R.; Welle, F. Post-consumer Poly(ethylene terephthalate) for direct food contact applications—Final proof of food law compliance. Dtsch. Lebensm.-Rundsch. 1999, 95, 424–427. [Google Scholar]
  71. Franz, R.; Welle, F. Recycled poly(ethylene terephthalate) for direct food contact applications: Challenge test of an inline recycling process. Food Addit. Contam. 2002, 19, 502–511. [Google Scholar] [CrossRef]
  72. Franz, R.; Mauer, A.; Welle, F. European survey on post-consumer poly(ethylene terephthalate) (PET) materials to determine contamination levels and maximum consumer exposure from food packages made from recycled PET. Food Addit. Contam. 2004, 21, 265–286. [Google Scholar] [CrossRef]
  73. Benyathiar, P.; Kumar, P.; Carpenter, G.; Brace, J.; Mishra, D.K. Polyethylene Terephthalate (PET) Bottle-to-Bottle Recycling for the Beverage Industry: A Review. Polymers 2022, 14, 2366. [Google Scholar] [CrossRef]
  74. Pinter, E.; Welle, F.; Mayrhofer, E.; Pechhacker, A.; Motloch, L.; Lahme, V.; Grant, A.; Tacker, M. Circularity study on pet bottle-to-bottle recycling. Sustainability 2021, 13, 7370. [Google Scholar] [CrossRef]
  75. Müller, K.; Sängerlaub, S.; Kramer, A.; Huber, C.; Fritsch, K. Temperature-dependent oxygen permeation through PET/MXD6-barrier blend bottles with and without oxygen absorber. Brew. Sci. 2011, 64, 161–167. [Google Scholar] [CrossRef]
  76. Sängerlaub, S.; Müller, K. Long-time performance of bottles made of pet blended with various concentrations of oxygen scavenger additive stored at different temperatures. Packag. Technol. Sci. 2017, 30, 45–58. [Google Scholar] [CrossRef]
  77. Sängerlaub, S.; Glas, C.E.; Schlemmer, D.; Müller, K. Influence of multiple extrusions of blends made of polyethylene terephthalate and an oxygen scavenger on processing and packaging-related properties. J. Plast. Film Sheet. 2020, 36, 260–284. [Google Scholar] [CrossRef]
  78. Thielen, M. Extrusion Blow Molding; Hanser Publications: Munich, Germany, 2021; ISBN 9781569908419. [Google Scholar]
  79. Zhang, J.; Gong, M.; Du, T.; Hen, C.; Wang, S.; Lu, X.; Li, K. Study on technology of room temperature yogurt in HDPE bottles. J. Food Sci. Technol. 2018, 36, 106–110. [Google Scholar] [CrossRef]
  80. Welle, F. Post-consumer contamination in high-density polyethylene (HDPE) milk bottles and the design of a bottle-to-bottle recycling process. Food Addit. Contam. 2005, 22, 999–1011. [Google Scholar] [CrossRef]
  81. Knights, M. Leading the way in IML packaging. Plast. Technol. 2005, 51, 88. [Google Scholar]
  82. Baur, E.; Harsch, G.; Moneke, M. Werkstoff-Führer Kunststoffe: Eigenschaften—Prüfungen—Kennwerte, 11th ed.; Hanser: Munich, Germany, 2019; ISBN 9783446457980. [Google Scholar]
  83. Qiu, R.; Qi, Y.; Wan, X. An event-related potential study of consumers’ responses to food bundles. Appetite 2020, 147, 104538. [Google Scholar] [CrossRef]
  84. Carroll, K.A.; Samek, A.; Zepeda, L. Consumer Preference for Food Bundles under Cognitive Load: A Grocery Shopping Experiment. Foods 2022, 11, 973. [Google Scholar] [CrossRef]
  85. Gell, M. Packaging innovations and evolution in the food & drinks sector. WRAP 2013. Available online: https://www.iopp.org/files/wrap_innovations.pdf (accessed on 1 May 2022).
  86. Becerril-Arreola, R.; Bucklin, R.E. Beverage bottle capacity, packaging efficiency, and the potential for plastic waste reduction. Sci. Rep. 2021, 11, 3542. [Google Scholar] [CrossRef] [PubMed]
  87. GVM Gesellschaft für Verpackungsmarktforschung mbH. Entwicklung von Konsumverhalten, Aufkommen und Materialeffizienz von Verpackungen, Mainz. 2022. Available online: https://www.bvse.de/dateien2020/2-PDF/01-Nachrichten/03-Kunststoff/2022/GVM_Studie_Konsum__Verpackung_-_Tag_der_Verpackung_2022.pdf (accessed on 1 May 2022).
  88. Licciardello, F.; Sapienza, G.; Mazzaglia, A.; D’Amico, L.; Tornatore, G.; Muratore, G. Packaging reduction to improve the sustainability of carbonated soft drinks. Ital. J. Food Sci. 2015, 2015, 1–6. [Google Scholar]
  89. Gaedeke, H. Trennverfahren—Schwimm/Sink-Verfahren: Modul 03—Entsorgung und Recycling. [ER+7]. Plastic 360. Available online: https://www.chemie.uni-wuerzburg.de/fileadmin/08010034/user_upload/plastic360/Zusatzmaterialien/ER_7_Schwimm-Sink-Verfahren.pdf (accessed on 1 May 2022).
  90. Sängerlaub, S.; Seibel, K.; Miesbauer, O.; Pant, A.; Kiese, S.; Rodler, N.; Schmid, M.; Müller, K. Functional properties of foamed and/or stretched polypropylene-films containing sodium chloride particles for humidity regulation. Polym. Test 2018, 65, 339–351. [Google Scholar] [CrossRef]
  91. Sängerlaub, S.; Böhmer, M.; Stramm, C. Influence of stretching ratio and salt concentration on the porosity of polypropylene films containing sodium chloride particles. J. Appl. Polym. Sci. 2013, 129, 1238–1248. [Google Scholar] [CrossRef]
  92. Sängerlaub, S.; Miesbauer, O.; Michael, L.; Müller, K.; Stramm, C.; Pecyna, M.; Langowski, H.-C. Humidity regulation by stretched PP and PLA films with dispersed CaCl2. J. Appl. Polym. Sci. 2018, 135, 45713. [Google Scholar] [CrossRef]
  93. Lechleitner, A.; Schwabl, D.; Schubert, T.; Bauer, M.; Lehner, M. Chemisches Recycling von gemischten Kunststoffabfällen als ergänzender Recyclingpfad zur Erhöhung der Recyclingquote. Österr. Wasser-Abfallw. 2020, 72, 47–60. [Google Scholar] [CrossRef]
  94. Kaiser, K.; Schmid, M.; Schlummer, M. Recycling of Polymer-Based Multilayer Packaging: A Review. Recycling 2018, 3, 1. [Google Scholar] [CrossRef]
  95. Lohse, H.; Weber, J.; Helduser, S.; Hauptmann, M.; Majschak, J.-P.; Enz, B.; Heibig, A. Pulling of paper and carton: Electrohydraulic drive system enables a flexible process design. Olhydraul. Pneum. 2010, 54, 118–123. [Google Scholar]
  96. Hauptmann, M.; Majschak, J.-P. New quality level of packaging components from paperboard through technology improvement in 3D forming. Packag. Technol. Sci. 2011, 24, 419–432. [Google Scholar] [CrossRef]
  97. Hauptmann, M.; Ehlert, S.; Majschak, J.-P. The effect of concave base shape elements on the three dimensional forming process of advanced paperboard structures. Packag. Technol. Sci. 2014, 27, 975–986. [Google Scholar] [CrossRef]
  98. Vishtal, A.; Hauptmann, M.; Zelm, R.; Majschak, J.-P.; Retulainen, E. 3D forming of paperboard: The influence of paperboard properties on formability. Packag. Technol. Sci. 2014, 27, 677–691. [Google Scholar] [CrossRef]
  99. Hauptmann, M.; Wallmeier, M.; Erhard, K.; Zelm, R.; Majschak, J.-P. The role of material composition, fiber properties and deformation mechanisms in the deep drawing of paperboard. Cellulose 2015, 22, 3377–3395. [Google Scholar] [CrossRef]
  100. Wallmeier, M.; Hauptmann, M.; Majschak, J.-P. New methods for quality analysis of deep-drawn packaging components from paperboard. Packag. Technol. Sci. 2015, 28, 91–100. [Google Scholar] [CrossRef]
  101. Hauptmann, M.; Kaulfürst, S.; Majschak, J.-P. Advances on geometrical limits in the deep drawing process of paperboard. BioResources 2016, 11, 10042–10056. [Google Scholar] [CrossRef]
  102. Hauptmann, M.; Majschak, J.-P. Characterization of influences on the wall stability of deep drawn paperboard shapes. BioResources 2016, 11, 2640–2654. [Google Scholar] [CrossRef]
  103. Hauptmann, M.; Weyhe, J.; Majschak, J.-P. Optimisation of deep drawn paperboard structures by adaptation of the blank holder force trajectory. J. Mater. Process. Technol. 2016, 232, 142–152. [Google Scholar] [CrossRef]
  104. Wallmeier, M.; Hauptmann, M.; Majschak, J.-P. The occurrence of rupture in deep-drawing of paperboard. BioResources 2016, 11, 4688–4704. [Google Scholar] [CrossRef]
  105. Wallmeier, M.; Noack, K.; Hauptmann, M.; Majschak, J.-P. Shape accuracy analysis of deep drawn packaging components made of paperboard. Nord. Pulp Pap. Res. J. 2016, 31, 323–332. [Google Scholar] [CrossRef]
  106. Hauptmann, M.; Kustermann, T.; Schmalholz, M.; Haug, H.; Majschak, J.-P. Examination of the transferability of technological key features of paperboard deep drawing towards the application in fast-running packaging machines. Packag. Technol. Sci. 2017, 30, 21–31. [Google Scholar] [CrossRef]
  107. Lenske, A.; Müller, T.; Penter, L.; Schneider, M.; Hauptmann, M.; Majschak, J.-P. Evaluating the factors influencing the friction behavior of paperboard during the deep drawing process. BioResources 2017, 12, 8340–8358. [Google Scholar] [CrossRef]
  108. Löwe, A.; Hauptmann, M.; Majschak, J.-P. The effect of ultrasonic oscillation on the quality of 3D shapes during deep-drawing of paperboard. BioResources 2017, 12, 7178–7194. [Google Scholar] [CrossRef]
  109. Löwe, A.; Hofmann, A.; Hauptmann, M. The use and application of ultrasonic vibrations in the 3D deformation of paper and cardboard. J. Mater. Process. Technol. 2017, 240, 23–32. [Google Scholar] [CrossRef]
  110. Müller, T.; Lenske, A.; Hauptmann, M.; Majschak, J.-P. Analysis of dominant process parameters in deep-drawing of paperboard. BioResources 2017, 12, 3530–3545. [Google Scholar] [CrossRef] [Green Version]
  111. Müller, T.; Lenske, A.; Hauptmann, M.; Majschak, J.-P. Method for fast quality evaluation of deep-drawn paperboard packaging components. Packag. Technol. Sci. 2017, 30, 703–710. [Google Scholar] [CrossRef]
  112. Müller, T.; Meyer, M.; Lenske, A.; Hauptmann, M.; Majschak, J.-P. Optical inline quality assessment of deep-drawn paperboard containers. J. Mater. Process. Technol. 2018, 262, 615–621. [Google Scholar] [CrossRef]
  113. Hauptmann, M. The path to formable cellulose-based barrier solutions in packaging. In Proceedings of the 17th Biennial TAPPI European PLACE Conference 2019, Porto, Portugal, 20–22 May 2019; TAPPI Press: Peachtree Corners, GA, USA, 2019; pp. 50–60, ISBN 9781510888012. [Google Scholar]
  114. Hofmann, A.; Wallmeier, M.; Hauptmann, M.; Majschak, J.-P. Characterization of the material elongation in the deep drawing of paperboard. Packag. Technol. Sci. 2019, 32, 287–296. [Google Scholar] [CrossRef]
  115. Lenske, A.; Müller, T.; Hauptmann, M.; Majschak, J.-P. New method to evaluate the frictional behavior within the forming gap during the deep drawing process of paperboard. BioResources 2019, 13, 5580–5597. [Google Scholar] [CrossRef]
  116. Müller, T.; Lenske, A.; Barbier, C.; Hauptmann, M.; Majschak, J.-P. Geometry-invariant wrinkle detection in sealing rims of paperboard containers. BioResources 2019, 14, 2536–2549. [Google Scholar] [CrossRef]
  117. Löwe, A.; Nikowski, A.; Hauptmann, M. Functional design of sonotrodes for deep-drawing of cardboard. BioResources 2020, 15, 2763–2773. [Google Scholar] [CrossRef]
  118. Balzarotti, S.; Maviglia, B.; Biassoni, F.; Ciceri, M.R. Glass vs. plastic: Affective judgments of food packages after visual and haptic exploration. Procedia Manuf. 2015, 3, 2251–2258. [Google Scholar] [CrossRef]
  119. Saint-Eve, A.; Lévy, C.; le Moigne, M.; Ducruet, V.; Souchon, I. Quality changes in yogurt during storage in different packaging materials. Food Chem. 2008, 110, 285–293. [Google Scholar] [CrossRef] [PubMed]
  120. Wang, C.; Qiu, L.; Zhang, W.; Wan, X. Influence of flavor variety and color variety on consumer preference and choices of yogurt bundles. Food Qual. Prefer. 2022, 96, 104424. [Google Scholar] [CrossRef]
  121. Schmidt, S.; Wellbrock, W. Alltäglicher nachhaltiger Konsum—Bewusster Umgang mit Lebensmitteln vs. skandalträchtige Verschwendung. In Nachhaltiger Konsum: Best Practices aus Wissenschaft, Unternehmenspraxis, Gesellschaft, Verwaltung und Politik; Wellbrock, W., Ludin, D., Eds.; Springer Fachmedien Wiesbaden: Wiesbaden, Germany, 2021; pp. 719–741. ISBN 978-3-658-33353-9. [Google Scholar]
  122. Leibinger, T. (Ed.) Downsizing bei Konsumgütern: Wahrnehmung und Reaktionen von Konsumenten; Springer Fachmedien: Wiesbaden, Germany, 2017; ISBN 978-3-658-18971-6. [Google Scholar]
  123. Bosiers, L.; Engelmann, S. Thermoformed packaging made of PLA. Kunsts Plast. Eur. 2003, 93, 21–23+48. [Google Scholar]
  124. Green, R.; Kunnemann, D. (Eds.) PLA—A Renewable/Sustainable Packaging Option. In Proceedings of the TAPPI 2006 PLACE Conference, Cincinnati, OH, USA, 17–21 September 2006. [Google Scholar]
  125. Colomines, G.; Domenek, S.; Ducruet, V.; Guinault, A. Influences of the crystallisation rate on thermal and barrier properties of polylactide acid (PLA) food packaging films. Int. J. Mater. Form. 2008, 1, 607–610. [Google Scholar] [CrossRef]
  126. Topiarzová, R.; Čablík, V.; Nezvalová, L.; Fečko, P. Launch of biodegradable pla bottles: A sociological survey on packaging material awareness in the Czech Republic. Rocz. Ochr. R. 2011, 13, 149–162. [Google Scholar]
  127. Moretti, C.; Hamelin, L.; Jakobsen, L.G.; Junginger, M.H.; Steingrimsdottir, M.M.; Høibye, L.; Shen, L. Cradle-to-grave life cycle assessment of single-use cups made from PLA, PP and PET. Resour. Conserv. Recycl. 2021, 169, 105508. [Google Scholar] [CrossRef]
  128. Aggarwal, A.; Langowski, H.-C. Packaging functions and their role in technical development of food packaging systems: Functional equivalence in yoghurt packaging. In Proceedings of the 27th CIRP Life Cycle Engineering Conference, LCE 2020, Grenoble, France, 13–15 May 2020; Brissaud, D., Zwolinski, P., Paris, H., Riel, A., Eds.; Elsevier: Amsterdam, The Netherlands, 2020; pp. 405–410, ISBN 22128271. [Google Scholar]
  129. Sinclair, R.G. The Case for Polylactic Acid as a Commodity Packaging Plastic. J. Macromol. Sci. Part A 1996, 33, 585–597. [Google Scholar] [CrossRef]
  130. Mikloskova, H.; Witte, F.; Joeres, E.; Terjung, N. Storage stability of plain stirred whole milk yoghurt (3.7% fat) packed in polylactic acid and polystyrene. Int. Dairy J. 2021, 120, 105088. [Google Scholar] [CrossRef]
  131. Naitove, M.H. Conference report: Bioplastics are breaking out of their ‘green’ niche. Plast. Technol. 2012, 58, 13–17+58–62. [Google Scholar]
  132. Petchwattana, N.; Naknaen, P. Influence of packaging material and storage time on physical, chemical and microbiological properties of set yogurt: A comparative study between modified biodegradable poly(lactic acid) and polypropylene. J. Eng. Sci. Technol. 2016, 11, 1437–1449. [Google Scholar]
  133. Leaversuch, R. Renewable PLA polymer gets ‘green light’ for packaging uses. Plast. Technol. 2002, 48, 50–55. [Google Scholar]
  134. Sari, N.; Suteja, S.; Sapuan, S.; Ilyas, R. Properties and Food Packaging Application of Poly-(Lactic) Acid. In Bio-Based Packaging: Material, Environmental and Economic Aspects; John Wiley & Sons Ltd.: Hoboken, NJ, USA, 2021; ISBN 9781119381228. [Google Scholar]
  135. Herrmann, C.; Rhein, S.; Sträter, K.F. Consumers’ sustainability-related perception of and willingness-to-pay for food packaging alternatives. Resour. Conserv. Recycl. 2022, 181, 106219. [Google Scholar] [CrossRef]
  136. Voet, V.; Folkersma, R.; Jager, J. Plastics in the Circular Economy; De Gruyter: Berlin, Germany, 2021; ISBN 9783110666762. [Google Scholar]
  137. Rudolph, N.; Kiesel, R.; Aumnate, C. Understanding Plastics Recycling: Economic, Ecological, and Technical Aspects of Plastic Waste Handling, 2nd ed.; Hanser Publishers: Munich, Germany, 2021; ISBN 9781569908464. [Google Scholar]
  138. Welle, F. Is PET bottle-to-bottle recycling safe? Evaluation of post-consumer recycling processes according to the EFSA guidelines. Resour. Conserv. Recycl. 2013, 73, 41–45. [Google Scholar] [CrossRef]
  139. Welle, F. Twenty years of PET bottle to bottle recycling—An overview. Resour. Conserv. Recycl. 2011, 55, 865–875. [Google Scholar] [CrossRef]
  140. Lehner, M.; Schlemmer, D.; Sängerlaub, S. Recycling of blends made of polypropylene and an iron-based oxygen scavenger—Influence of multiple extrusions on the polymer stability and the oxygen absorption capacity. Polym. Degrad. Stab. 2015, 122, 122–132. [Google Scholar] [CrossRef]
  141. Ladhari, A.; Kucukpinar, E.; Stoll, H.; Sängerlaub, S. Comparison of properties with relevance for the automotive sector in mechanically recycled and virgin polypropylene. Recycling 2021, 6, 76. [Google Scholar] [CrossRef]
  142. Schlummer, M.; Maurer, A.; Agulla, K. That’s the “solution”! Kunsts Int. 2008, 98, 59–61. [Google Scholar]
  143. Strangl, M.; Fell, T.; Schlummer, M.; Maeurer, A.; Buettner, A. Characterization of odorous contaminants in post-consumer plastic packaging waste using multidimensional gas chromatographic separation coupled with olfactometric resolution. J. Sep. Sci. 2017, 40, 1500–1507. [Google Scholar] [CrossRef]
  144. Strangl, M.; Schlummer, M.; Maeurer, A.; Buettner, A. Comparison of the odorant composition of post-consumer high-density polyethylene waste with corresponding recycled and virgin pellets by combined instrumental and sensory analysis. J. Clean. Prod. 2018, 181, 599–607. [Google Scholar] [CrossRef]
  145. Strangl, M.; Ortner, E.; Buettner, A. Evaluation of the efficiency of odor removal from recycled HDPE using a modified recycling process. Resour. Conserv. Recycl. 2019, 146, 89–97. [Google Scholar] [CrossRef]
  146. Cabanes, A.; Strangl, M.; Ortner, E.; Fullana, A.; Buettner, A. Odorant composition of post-consumer LDPE bags originating from different collection systems. Waste Manag. 2020, 104, 228–238. [Google Scholar] [CrossRef]
  147. Strangl, M.; Ortner, E.; Fell, T.; Ginzinger, T.; Buettner, A. Odor characterization along the recycling process of post-consumer plastic film fractions. J. Clean. Prod. 2020, 260, 121104. [Google Scholar] [CrossRef]
  148. Strangl, M.; Lok, B.; Breunig, P.; Ortner, E.; Buettner, A. The challenge of deodorizing post-consumer polypropylene packaging: Screening of the effect of washing, color-sorting and heat exposure. Resour. Conserv. Recycl. 2021, 164, 105143. [Google Scholar] [CrossRef]
  149. Steenis, N.D.; van Herpen, E.; van der Lans, I.A.; Ligthart, T.N.; van Trijp, H.C. Consumer response to packaging design: The role of packaging materials and graphics in sustainability perceptions and product evaluations. J. Clean. Prod. 2017, 162, 286–298. [Google Scholar] [CrossRef]
  150. Niedziela, M.M.; Jordan, A.; Stone, H. Tasteful packaging: How health and ethical messaging can affect the consumer experience. Agro Food Ind. Hi-Tech 2016, 27, 34–37. [Google Scholar]
  151. Arrúa, A.; Vidal, L.; Antúnez, L.; Machín, L.; Martínez, J.; Curutchet, M.R.; Giménez, A.; Ares, G. Influence of label design on children’s perception of 2 snack foods. J. Nutr. Educ. Behav. 2017, 49, 211–217.e1. [Google Scholar] [CrossRef]
  152. Schifferstein, H.N.; Lemke, M.; de Boer, A. An exploratory study using graphic design to communicate consumer benefits on food packaging. Food Qual. Prefer. 2022, 97, 104458. [Google Scholar] [CrossRef]
  153. Wang, F.; Wang, H.; Cho, J.H. Consumer preference for yogurt packaging design using conjoint analysis. Sustainability 2022, 14, 3463. [Google Scholar] [CrossRef]
  154. Camacho, W.; Karlsson, S. NIR, DSC, and FTIR as quantitative methods for compositional analysis of blends of polymers obtained from recycled mixed plastic waste. Polym. Eng. Sci. 2001, 41, 1626–1635. [Google Scholar] [CrossRef]
  155. Kulcke, A.; Gurschler, C.; Spöck, G.; Leitner, R.; Kraft, M. On-line classification of synthetic polymers using near infrared spectral imaging. J. Near Infrared Spectrosc. 2003, 11, 71–81. [Google Scholar] [CrossRef]
  156. Tachwali, Y.; Al-Assaf, Y.; Al-Ali, A.R. Automatic multistage classification system for plastic bottles recycling. Resour. Conserv. Recycl. 2007, 52, 266–285. [Google Scholar] [CrossRef]
  157. Becker, W.; Sachsenheimer, K.; Klemenz, M. Detection of black plastics in the middle infrared spectrum (MIR) using photon Up-conversion technique for polymer recycling purposes. Polymers 2017, 9, 435. [Google Scholar] [CrossRef] [PubMed]
  158. Yan, H.; Siesler, H.W. Identification performance of different types of handheld near-infrared (NIR) spectrometers for the recycling of polymer commodities. Appl. Spectrosc. 2018, 72, 1362–1370. [Google Scholar] [CrossRef]
  159. Küppers, B.; Schloegl, S.; Oreski, G.; Pomberger, R.; Vollprecht, D. Influence of surface roughness and surface moisture of plastics on sensor-based sorting in the near infrared range. Waste Manag. Res. 2019, 37, 843–850. [Google Scholar] [CrossRef]
  160. Li, J.; Li, C.; Liao, Q.; Xu, Z. Environmentally-friendly technology for rapid on-line recycling of acrylonitrile-butadiene-styrene, polystyrene and polypropylene using near-infrared spectroscopy. J. Clean. Prod. 2019, 213, 838–844. [Google Scholar] [CrossRef]
  161. Signoret, C.; Caro-Bretelle, A.-S.; Lopez-Cuesta, J.-M.; Ienny, P.; Perrin, D. MIR spectral characterization of plastic to enable discrimination in an industrial recycling context: I. Specific case of styrenic polymers. Waste Manag. 2019, 95, 513–525. [Google Scholar] [CrossRef]
  162. Chen, X.; Kroell, N.; Feil, A.; Pretz, T. Determination of the composition of multilayer plastic packaging with nir spectroscopy. Detritus 2020, 13, 62–66. [Google Scholar] [CrossRef]
  163. Akopian, D.; Creutzburg, R.; Bassey, U.; Rojek, L.; Hartmann, M.; Creutzburg, R.; Volland, A. (Eds.) The Potential of NIR Spectroscopy in the Separation of Plastics for Pyrolysis. In Mobile Devices and Multimedia: Enabling Technologies, Algorithms, and Applications 2021, Proceedings of the IS&T International Symposium on Electronic Imaging 2021, held online, 11–28 January 2021; Society for Imaging Science and Technology: Springfield, VA, USA, 2021. [Google Scholar]
  164. Schmidt, J.; Auer, M.; Moesslein, J.; Wendler, P.; Wiethoff, S.; Lang-Koetz, C.; Woidasky, J. Challenges and solutions for plastic packaging in a circular economy. Chem. Ing. Tech. 2021, 93, 1751–1762. [Google Scholar] [CrossRef]
  165. Adarsh, U.K.; Kartha, V.B.; Santhosh, C.; Unnikrishnan, V.K. Spectroscopy: A promising tool for plastic waste management. TrAC Trends Anal. Chem. 2022, 149, 116534. [Google Scholar] [CrossRef]
  166. Neo, E.; Yeo, Z.; Low, J.; Goodship, V.; Debattista, K. A review on chemometric techniques with infrared, Raman and laser-induced breakdown spectroscopy for sorting plastic waste in the recycling industry. Resour. Conserv. Recycl. 2022, 180, 106217. [Google Scholar] [CrossRef]
  167. Bosset, J.O.; Daget, N.; Desarzens, C.; Dieffenbacher, A.; Flückiger, E.; Lavanchy, P.; Nick, B.; Pauchard, J.-P.; Tagliaferri, E. The influence of light transmittance and gas permeability of various packing materials on the quality of whole natural yoghurt during storage. LWT Food Sci. Technol. 1986, 19, 104–116. [Google Scholar]
  168. Frederiksen, C.S.; Haugaard, V.K.; Poll, L.; Miquel Becker, E. Light-induced quality changes in plain yoghurt packed in polylactate and polystyrene. Eur. Food Res. Technol. 2003, 217, 61–69. [Google Scholar] [CrossRef]
  169. Böhner, N.; Adolf, L.; Tybussek, T.; Rieblinger, K.; Verin, M.; Langowski, H.-C. Influence of novel retail lighting on the quality of coffee cream in different types of packaging. Int. Dairy J. 2017, 64, 37–47. [Google Scholar] [CrossRef]
  170. Beauchamp, J.; Zardin, E.; Silcock, P.; Bremer, P.J. Monitoring photooxidation-induced dynamic changes in the volatile composition of extended shelf life bovine milk by PTR-MS. J. Mass Spectrom. 2014, 49, 952–958. [Google Scholar] [CrossRef]
  171. Zardin, E.; Silcock, P.; Siefarth, C.; Bremer, P.J.; Beauchamp, J. Dynamic changes in the volatiles and sensory properties of chilled milk during exposure to light. Int. Dairy J. 2016, 62, 35–38. [Google Scholar] [CrossRef]
  172. Fellows, P.J. 25—Packaging. In Food Processing Technology, 3rd ed.; Fellows, P.J., Ed.; Woodhead Publishing Series in Food Science, Technology and Nutrition; Woodhead Publishing: Sawston, UK, 2009; pp. 713–781. ISBN 978-1-84569-216-2. [Google Scholar]
  173. Grayhurst, P. 7—Glass packaging. In Packaging Technology; Emblem, A., Emblem, H., Eds.; Woodhead Publishing: Sawston, UK, 2012; pp. 109–121. ISBN 978-1-84569-665-8. [Google Scholar]
  174. Ten Klooster, R.; de Koeijer, B.; de Lange, J. Towards a Generic Set of Packaging Material Key Figures. In Proceedings of the 28th IAPRI Symposium on Packaging, Lausanne, Switzerland, 9–12 May 2017. [Google Scholar]
  175. Lilienfeld, R. A Study of Packaging Efficiency as It Relates to Waste Prevention; Prepared by the Editors of The ULS Report January 2016; ULS: Louisville, CO, USA, 2016. [Google Scholar]
  176. Kauertz, B.; Busch, M.; Bader, J. Ökobilanzielle Betrachtung von Getränkeverbundkartons in Deutschland. In Den Getränkesegmenten Säfte und Nektare Sowie H-Milch und Frischmilch; IFEU: Heidelberg, Germany, 2020. [Google Scholar]
Dairy 03 00046 g001 550
Figure 1. From left to right: cup directly printed, cup with paper label, cup with printed carton sleeve, cup with shrink sleeve, cup with sleeve.
Figure 1. From left to right: cup directly printed, cup with paper label, cup with printed carton sleeve, cup with shrink sleeve, cup with sleeve.
Dairy 03 00046 g001
Dairy 03 00046 g002 550
Figure 2. Analysed product categories; numbers: number of samples, n = 150.
Figure 2. Analysed product categories; numbers: number of samples, n = 150.
Dairy 03 00046 g002
Dairy 03 00046 g003 550
Figure 3. Analysed packaging mean categories; numbers: number of samples, n = 150.
Figure 3. Analysed packaging mean categories; numbers: number of samples, n = 150.
Dairy 03 00046 g003
Dairy 03 00046 g004 550
Figure 4. Amount of single packagings (1) and single packagings in bundles of 2, 4, 6, 8 and 12 smaller units; numbers: number of samples, n = 150.
Figure 4. Amount of single packagings (1) and single packagings in bundles of 2, 4, 6, 8 and 12 smaller units; numbers: number of samples, n = 150.
Dairy 03 00046 g004
Dairy 03 00046 g005 550
Figure 5. Filling ratios of different packaging categories, simplified density of product 1 g/cm3, n = 150.
Figure 5. Filling ratios of different packaging categories, simplified density of product 1 g/cm3, n = 150.
Dairy 03 00046 g005
Dairy 03 00046 g006 550
Figure 6. Polymers used for cups; number: number of samples, n = 105.
Figure 6. Polymers used for cups; number: number of samples, n = 105.
Dairy 03 00046 g006
Dairy 03 00046 g007 550
Figure 7. Decoration used for cups, without glass packaging; number: number of samples, IML: in-mould label, n = 137.
Figure 7. Decoration used for cups, without glass packaging; number: number of samples, IML: in-mould label, n = 137.
Dairy 03 00046 g007
Dairy 03 00046 g008 550
Figure 8. Used fibre material for fibre-based packagings; numbers: number of samples, n = 54.
Figure 8. Used fibre material for fibre-based packagings; numbers: number of samples, n = 54.
Dairy 03 00046 g008
Dairy 03 00046 g009 550
Figure 9. Colour of the plastic body of the packaging; numbers: number of samples, n = 150.
Figure 9. Colour of the plastic body of the packaging; numbers: number of samples, n = 150.
Dairy 03 00046 g009
Dairy 03 00046 g010a 550Dairy 03 00046 g010b 550
Figure 10. Closure weight versus packaging weight (all parts including wrapper and shrink label if applicable), (a): cup, (b): bucket, (c): pouch, (d): plastic bottle, (e): glass packaging, (f): brick; straight line equation with origin 0 applied.
Figure 10. Closure weight versus packaging weight (all parts including wrapper and shrink label if applicable), (a): cup, (b): bucket, (c): pouch, (d): plastic bottle, (e): glass packaging, (f): brick; straight line equation with origin 0 applied.
Dairy 03 00046 g010aDairy 03 00046 g010b
Dairy 03 00046 g011 550
Figure 11. Ratio of closure weight to packaging weight (all parts including wrapper and shrink label if applicable).
Figure 11. Ratio of closure weight to packaging weight (all parts including wrapper and shrink label if applicable).
Dairy 03 00046 g011
Dairy 03 00046 g012 550
Figure 12. Food product weight (from packaging declaration) versus used packaging weight, all packaging components used (e.g., labels, wrappings, shrink sleeves); (a): cup, (b): bucket, (c): pouch, (d): plastic bottle, (e): glass packaging, (f): brick; straight line equation with origin 0 applied.
Figure 12. Food product weight (from packaging declaration) versus used packaging weight, all packaging components used (e.g., labels, wrappings, shrink sleeves); (a): cup, (b): bucket, (c): pouch, (d): plastic bottle, (e): glass packaging, (f): brick; straight line equation with origin 0 applied.
Dairy 03 00046 g012
Dairy 03 00046 g013 550
Figure 13. Packaging efficiencies for different types of packaging; packagings include all packaging components (labels, wrappings, shrink sleeves, lid).
Figure 13. Packaging efficiencies for different types of packaging; packagings include all packaging components (labels, wrappings, shrink sleeves, lid).
Dairy 03 00046 g013
Dairy 03 00046 g014a 550Dairy 03 00046 g014b 550
Figure 14. Packaging efficiencies over increasing product weights for different types of packaging, all packaging components are included; (a): cup, (b): bucket, (c): pouch, (d): plastic bottle, (e): glass packaging, (f): brick.
Figure 14. Packaging efficiencies over increasing product weights for different types of packaging, all packaging components are included; (a): cup, (b): bucket, (c): pouch, (d): plastic bottle, (e): glass packaging, (f): brick.
Dairy 03 00046 g014aDairy 03 00046 g014b
Dairy 03 00046 g015 550
Figure 15. Packaging efficiencies (rim full weight divided by packaging weight; packagings filled with water) for different types of packaging, (a): all packaging components included (with labels, wrappings, shrink sleeves if applicable), (b): only body (separatable components are excluded).
Figure 15. Packaging efficiencies (rim full weight divided by packaging weight; packagings filled with water) for different types of packaging, (a): all packaging components included (with labels, wrappings, shrink sleeves if applicable), (b): only body (separatable components are excluded).
Dairy 03 00046 g015
Dairy 03 00046 g016 550
Figure 16. Recycling advice on packagings, numbers: number of samples, n = 150.
Figure 16. Recycling advice on packagings, numbers: number of samples, n = 150.
Dairy 03 00046 g016
Dairy 03 00046 g017a 550Dairy 03 00046 g017b 550
Figure 17. Packaging use related to food costs; (a): non-glass packaging, (b): glass packaging.
Figure 17. Packaging use related to food costs; (a): non-glass packaging, (b): glass packaging.
Dairy 03 00046 g017aDairy 03 00046 g017b
Table
Table 1. Filling weight distribution of different packaging means; number in field: amount of packagings.
Table 1. Filling weight distribution of different packaging means; number in field: amount of packagings.
Filling Weight/gCupBucketPouchBottleGlass PackagingBrick∑
502 2
601 1
65 1 1
70 1 1
751 1
80 1 1
90 1 1 2
1005 114 11
1154 4
1201 1
1253 2 5
1301 1
15029 1 30
1602 2
1755 5
1802 2
20014 1 15
2301 1
2508 12 11
2551 1
3003 3
330 1 1
375 1 1
4008 19
423 1 1
4501 1 2
50016 73228
100015 17
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Share and Cite

MDPI and ACS Style

Kostic, D.; Hoffmann, U.; Fürtauer, S.; Fell, T.; Yilmaz, C.; Burth, D.; Sängerlaub, S. Packaging Weight, Filling Ratio and Filling Efficiency of Yogurt and Relevant Packagings Depending on Commercial Packaging Design, Material, Packaging Type and Filling Quantity. Dairy 2022, 3, 668-692. https://doi.org/10.3390/dairy3030046

AMA Style

Kostic D, Hoffmann U, Fürtauer S, Fell T, Yilmaz C, Burth D, Sängerlaub S. Packaging Weight, Filling Ratio and Filling Efficiency of Yogurt and Relevant Packagings Depending on Commercial Packaging Design, Material, Packaging Type and Filling Quantity. Dairy. 2022; 3(3):668-692. https://doi.org/10.3390/dairy3030046

Chicago/Turabian Style

Kostic, Dejan, Udo Hoffmann, Siegfried Fürtauer, Tanja Fell, Cihat Yilmaz, Dirk Burth, and Sven Sängerlaub. 2022. "Packaging Weight, Filling Ratio and Filling Efficiency of Yogurt and Relevant Packagings Depending on Commercial Packaging Design, Material, Packaging Type and Filling Quantity" Dairy 3, no. 3: 668-692. https://doi.org/10.3390/dairy3030046

Article Metrics

Back to TopTop