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Article

Fresh-Cut Salads: Consumer Acceptance and Quality Parameter Evolution during Storage in Domestic Refrigerators

by
José M. Lorente-Mento
1,
Juan M. Valverde
2,
María Serrano
1 and
María T. Pretel
1,*
1
Department Applied Biology, University Miguel Hernández, Ctra Beniel, km 3.2, Orihuela, 03312 Alicante, Spain
2
Department Food Technology, University Miguel Hernández, Ctra Beniel, km 3.2, Orihuela, 03312 Alicante, Spain
*
Author to whom correspondence should be addressed.
Sustainability 2022, 14(6), 3473; https://doi.org/10.3390/su14063473
Submission received: 28 February 2022 / Revised: 10 March 2022 / Accepted: 13 March 2022 / Published: 16 March 2022
(This article belongs to the Special Issue Sustainable Agrifood Technologies)
Browse Figures
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Abstract

:
Ready-to-eat fresh-cut salads (RTESs) are fresh-cut vegetables that have been minimally processed and remain alive until consumption. A survey with 297 respondents was performed, showing that most respondents consumed RTESs composed of various vegetables once or twice a week. The most important items for consumers’ RTESs purchasing intention were the expiration date and the absence of exudates and brown and dehydrated leaves, while after storage in domestic refrigerators, the most important item for consumption refusal was the presence of strange odours. On the other hand, among the non-consumers of RTESs, the most important reason for not buying this kind of produce was the use of plastic packaging. Microbiological analysis of RTESs (composed of corn salads, radicchio and escarole leaves) showed that moulds, yeasts and psychrophilic aerobic microflora remained unchanged from buying to the expiration date, while increases occurred in mesophilic aerobic microflora, although all of them were within safety levels for consumption even after 4 days of the expiration date. Finally, total phenolics and antioxidant activity were higher in corn salads followed by radicchio and escarole leaves, and generally, no significant changes occurred in the bioactive compounds of RTESs during storage in domestic refrigerators.

1. Introduction

Eating habits have changed in industrialised countries mainly due to the reduced time available for food preparation and the emerging consumer’s demand for healthy and time-saving dietary solutions [1,2,3,4]. In this sense, the consumption of ready-to-eat salads (RTESs) has increased noticeably in the last years in developed counties since consumers perceive them as fresh, safe, nutritional and healthy products, which can be consumed without preparation, are 100% edible and socially appreciated as save-time and very high-quality products [4,5,6,7,8]. RTESs are minimally processed products. Their processing includes the selection of the plant material, cutting, washing, drying and packaging in plastic containers [9], which should be performed under highly hygienic conditions in order to avoid microbiological contamination during processing [10,11]. RTESs maintain sensorial, nutritional and microbiological quality for 5–7 days when stored at 4–6 °C in domestic refrigerators, their shelf life being shorter than the raw products [4,12,13].
Quality losses in RTESs are mainly due to microbial growth, which is increased by juice cellular leakage as a consequence of the cutting process [11,14,15,16]. Vegetables growing are inevitably contaminated by microorganisms present in soil and irrigation water, which can get internalised in the plant’s body, and contamination can also occur during each step of the production chain [17,18]. According to European Regulation (EC) No 1441/2007, concentrations of Listeria monocytogenes lower than 100 colony-forming units (CFU) per g and the absence of Salmonella spp. are essential criteria to define the safety of RTESs during their shelf life. There are no mandatory microbiological criteria for total aerobic mesophilic and E. coli, although several guidelines recommend as acceptable CFUg−1 lower than 106 and 102, respectively [19,20]. Browning and oxidation of the cut surfaces are other factors responsible for RTES quality losses [1,12,21]. Moreover, nutritional and functional quality losses also occur during the storage of RTESs. The functional properties of vegetable produce are due to bioactive compounds, such as fibre, phenolic compounds (phenolic acids and flavonoids), terpenes, phytosterols and carotenoids, among others [21,22,23]. Phenolic compounds have the ability to scavenge free radicals, acting as antioxidants with important benefits for reducing cell oxidative stress and leading to preventing degenerative disease development [23,24].
On the other hand, RTESs are expensive compared to the original products, being affordable for medium–high purchasing power consumers [5,6]. In some previous reports, key points and factors during RTES processing to obtain high-quality products have been addressed [1,10,25]. However, as far as we know, no information is available in the literature regarding factors determining consumers’ purchasing behaviour of RTESs, their consumption patterns and frequencies and the evolution of RTES quality properties during storage in domestic refrigerators. Thus, this research aims to determine the most important reasons influencing and dissuading consumers in purchasing RTESs by surveying 297 respondents. The survey results could be useful to the industry by permitting the development of new products according to consumers’ preferences. In addition, microbiological, sensory and functional quality properties were evaluated during storage in domestic refrigerators in a commercial RTES composed of corn salads, escarole leaves and radicchio.

2. Materials and Methods

2.1. Survey of Consumers of RTESs and Ethical Standards Disclosure

The questionnaire aimed to assess Spanish people’s regularity in consuming RTESs alongside the reasons underlying their consumption patterns. This study was conducted according to the guidelines laid down in the Declaration of Helsinki, and all procedures involving research study participants were approved by the Ethics Committee of the University Miguel Hernández (reference DBA.MPP.01.21). The participants’ consent was asked for in a previous contact, and the questionnaire was sent only to participants who indicated their positive consent to participate in the survey. The personal features of the respondents (gender, age, purchasing power according to residence, education level and monthly income) were taken under principles of anonymity and confidentiality, and the data obtained were used exclusively for the present study. The questionnaire was made with Google Forms, and responses from 297 participants, whose personal characteristics are shown in Table 1, were received. Most of the participants (44.3%) were 36–50 years old, followed by 30.7% of the participants who were 51–65 years old, while less than 30% were between 18 and 35 years old. More than 70% of the participants lived as a couple with or without children, had high education levels and had a permanent job. Four of the respondents were unaware of RTESs’ existence. These respondents were omitted from the survey. Sixty-nine were not consumers of freshly cut salads. Accordingly, these participants were asked about the level of importance (none, little, medium, quite and very much) they attached to different reasons for no consumption of RTESs (Questionnaire is in Supplementary File). The remaining 224 respondents were consumers of RTESs and were asked about their frequency of consumption and the type of salads they consumed (single ingredient, several ingredients and both types). In addition, the value of different aspects by consumers when buying and consuming RTESs (none, little, medium, quite and very much) was evaluated (Questionnaire is in Supplementary File).

2.2. Plant Material

RTESs from a commercial brand composed of corn salads (Valerianella locusta L.), escarole leaves (Cichorium endivia L.) and radicchio (Cichorium intybus L) were purchased at a supermarket on the same day as delivery. They were transported to the laboratory in a thermic bag and stored in a domestic refrigerator. Three RTES bags were taken at day 0 (purchasing day) and after 4, 7 (one day after the sell-by date) and 11 (5 days after sell-by date) days of storage. The refrigerator was opened several times a day to simulate real conditions, and the temperature ranged from 4 to 7 °C.

2.3. Microbiological Analysis

Microbiological analyses were performed according to Sanchez-Bell et al. [26]. Briefly, a 10 g sample of each salad was homogenised with 90 mL of sterile peptone water for 2 min in a sterilised blender. Serial dilutions (1:10) were aseptically made from the homogenate, under the laminar flow hood, and inoculated on the different plates. Total mesophilic microorganisms were counted in Petri dishes filled with agar (PCA) and incubated at 30 °C for 48 h. Moulds and yeasts were counted in Petri dishes filled with Rosa de Bengala (RBA) incubated at 25 °C for 5 days. Psicrophilic microorganisms were counted in PCA incubated at 5 °C for 10 days. Data are expressed as log CFU g−1 and are the mean ± SE of three bags or replicates.

2.4. Determination of Total Phenolic Compounds and Antioxidant Activity

Total phenolic content and antioxidant activity were measured in each vegetable ingredient of RTESs independently: corn salads, radicchio and escarole, the last one being separated into white and green leaf portions. Extractions were performed by homogenising 5 g of tissue with 10 mL of methanol:water (8:2) by using a mortar and pestle. The extracts were centrifuged at 12,000× g for 15 min at 4 °C, and the supernatant was used to quantify total phenolic content with Folin–Ciocalteu reagent, as previously described by Serrano et al. [27]. Supernatants were also used to quantify total antioxidant activity by using horse-radish-ABTS-H2O2 assay, according to Asencio et al. [28].

2.5. Sensorial Analysis

A semi-trained panel of 5 judges performed the sensorial analysis on each independent ingredient of RTESs. For each one, judges evaluated decay symptoms, browning, firmness, dehydration and overall appearance on a scale from 0 (dislike extremely) to 10 (like extremely). Judges had at least one year of experience evaluating fresh vegetable products and were previously pre-trained on the parameters to be evaluated in these RTESs.

2.6. Statistical Analysis

Data of evaluated parameters during storage were submitted to an analysis of variance (ANOVA) by using the SPSS software version 20 (SPSS Inc., Chicago, IL, USA), and differences at p < 0.05 were considered significant. In the figures, LSD values are shown.

3. Results and Discussion

3.1. Responses to the Questionnaire

The survey revealed that 4 out of the 297 respondents did not know of RTESs’ existence, 69 did not consume them, and 224 were consumers of these prepared salads. The main reason given for not consuming RTESs was related to environmental issues, since 79.7% of the respondents gave between medium and very much importance to the use of plastic films in the packaging of RTESs (Table 2). The following reason for no consumption, stated by 58% of consumers, was that they thought these products were not as healthy as whole vegetables, and they gave medium (31.9%), quite (11.6%) or very much (14.5%) importance to this item. However, more than 40% of the consumers gave none or little importance to price, and thus, although RTESs are more expensive than whole products, this higher price is not the main reason for not consuming these products. Finally, the appearance of the product was not an important reason for consumption either, since 76.7% of the consumers rated this as having no, little or medium importance (Table 2). In agreement with our results, Dinnella et al. [29] reported that respondents gave more importance to the use of environmentally friendly packages in fresh-cut salads than to their sensorial properties. According to the present results, a sector of the Spanish population thinks that fresh and whole vegetables are healthier than RTESs and that plastic packaging of RTESs is not environmentally friendly, being the main reasons discouraging them to buy these kinds of products. However, these RTES disadvantages could be reduced if clear information regarding safety, nutritional and health properties of the cut vegetables and the environmental impact of the packaging were provided in RTESs labels, as previously suggested by other authors [29,30,31].
On the other hand, 224 out of the 297 participants (75.7%) were consumers of RTESs, and among the RTES consumers most of them ate RTESs once or twice a week. RTESs composed of a mixture of ingredients were consumed by 56.5% of the respondents, although a high percentage of them (38%) were consumers of both types of RTESs, with single or various ingredients (Table 3). Thus, consumers of RTESs are used to regularly eating these kinds of products, as usually occurs with other foods [29,32,33,34,35].
With respect to the level of importance (none, little, medium, quite and very much) that consumers gave to different items at the time of purchasing RTESs, results showed that 85.7 and 76.3% of the respondents gave medium to very much importance to the mix of ingredients and price, respectively (Table 4). In addition, it is worth noting that most consumers (ca. 70%) gave no or little importance to the presence of dressing and cutlery in the package of RTESs, while 71.9% gave medium to very high importance to the amount of plastic in the packaging of RTESs. Moreover, a high percentage of consumers (57.1%) scored the content of bioactive compounds in RTESs as quite or very much important, showing that they are aware of the beneficial health effects of vegetable consumption, either as fresh products or in RTESs. On the contrary, no consumers of RTESs thought that fresh vegetables are healthier than RTESs, which could be related to the education levels of consumers.
Expiration date and appearance (presence of exudates and brown and dehydrated leaves) were the most important items determining consumers’ RTESs purchase intention (Table 4), in agreement with Dinnella et al. [29]. Thus, the expiration date was considered as quite (26.3%) or very much important (53.6%), and the presence of exudates and brown and dehydrated leaves was rated as very much important by 61.6, 66.5 and 70.5% of consumers, respectively (Table 4). Accordingly, Ares et al. [12] showed that these quality traits were the most important factors responsible for consumers’ rejection of lettuce RTESs at the time of purchasing. However, the scores given by consumers to these quality traits for RTES consumption after storage at home were different. Thus, the expiration date had scored lower than at the time of buying and scores for the presence of exudates and brown and dehydrated leaves decreased almost ten points (Table 4). It is worth noting that the most important aspect for refusing RTES consumption was the presence of strange odours, for which most of the respondents (71%) gave very much importance.
In general, the results showed that consumers were more exigent of the high-quality traits of RTESs at the time of buying than at the time of consumption. In fact, with respect to the question “Would you buy the salad if any of the valued aspects failed?” 64.4% would never buy the RTESs while 50.3% would never eat them (Table 5). However, just 4.3% of the respondents were worried about wasting food and would be able to consume RTESs even if any of the quality traits failed, which is a surprising result contrasting with the awareness for environmental issues addressed by respondents regarding the use of plastics in RTESs. Thus, consumers seem not to associate waste of food with environmental risks, according to previous reports [36,37,38] despite the fact that this is one of the most important factors for reducing human environmental impact [34,35,38,39,40,41]. Nevertheless, the waste of fresh-cut salads could be reduced if consumed as soon as possible after buying [42]. Finally, 23.9% of consumers would buy RTESs even if any of their quality traits failed depending on price, expiration date and overall appearance (Table 5), which would justify a discount on these products being offered by supermarkets when they are close to the expiration date.
This survey pointed out that consumers gave high importance to the properties of the RTESs related to sensory, nutritional and health beneficial effect aspects. Thus, an experiment was performed to evaluate the evolution of some of these properties in RTESs during storage in a domestic refrigerator.

3.2. Evolution of Quality Parameters of RTESs in a Domestic Refrigerator

3.2.1. Microbiological Quality

Counts for moulds and yeast were 4.27 ± 0.24 log CFU g−1 at day 0 and remained without significant changes (p > 0.05) until day 7 (one day after the expiration date), increasing up to 5.38 ± 0.33 log CFU g−1 at day 11. Marinelli et al. [14] reported an increase of 2 log CFU g−1 in moulds and yeast count in ready-to-eat salads during nine days of storage, although initial values were higher than those found in the present experiment, showing that sanitising operations are significant tasks to preserve microbiological quality in RTESs. The major fungi species identified in RTESs have been reported to be Cladosporium, Penicillium, Alternaria and Geotrichum spp., with percentages of 35%, 20%, 15% and 15%, respectively, being the primary fungi responsible for inducing decay in a few days [15]. Ramos et al. [10] reported that the count of total mesophilic microorganisms in recently packaged RTESs was 103–106 CFU g−1 and very similar (103–109 CFU g−1) when they arrived at the supermarket or sale point [10]. Accordingly, Arienzo et al. [9] reported that 100% of the samples of baby leaves in ready-to-eat salads displayed more than 6 log CFU g−1 for total mesophilic microorganism on the packaging date, increasing up to 7.5 CFU g−1 at the expiration date. Therefore, measures of the CFU of total mesophilic could be a good tool to evaluate sanitary conditions in RTESs during processing. In the present experiment, counts for total mesophilic microorganisms were 4.54 ± 0.76 CFU g−1 at day 0 and increased significantly (p < 0.05), up to 6.22 ± 0.37 and 6.47 ± 0.28 CFU g−1, after 7 and 11 days of storage, respectively (Figure 1). However, counts for total mesophilic were at acceptable levels and safety for consumption, according to Ramos et al. [10], Miceli et al. [43] and Manzzoco et al. [42], even three days after the expiration date. Accordingly, Benicardino et al. [44] reported that total mesophilic count increased by 2 CFU g−1 from packaging to the expiration date, although it is worth noting that the initial counts were 2 CFU g−1 higher in their studies than in the present one.
With respect to psychrophilic aerobic microflora, values remained unchanged (ca. 6.2 log CFU g−1) from day 0 to day 7 of storage and increased by 1.0 log CFU g−1 at day 11 (Figure 1). Among psychrophilic microorganisms, Pseudomonas fluorescens has been identified as the main psychrophilic microorganism responsible for alterations in modified atmosphere-packaged salads [45,46] with values of 6.3 log CFU g−1 at the expiration date, similar to counts for psychrophilic microorganisms found in the present experiment. However, in this previous study, mesophilic microorganisms were out of the safety limit and mould and yeast counts were higher than in the present study. The count increases for all these microorganisms in RTESs during storage in domestic refrigerators and could be accelerated by temperature changes due to the continuous opening of the fridge since a temperature increase of up to 8–10 °C for more prolonged periods has been reported [16].

3.2.2. Functional Quality of RTESs Ingredients during Storage

Phenolic compounds are the major attributes responsible for antioxidant activity and the functional properties of vegetable products [22,23,24], and thus, their content was evaluated in each independent ingredient of the RTESs during storage. Corn salads had the highest total phenolic content, followed by radicchio, while the lowest levels were found in escarole, mainly in the white part of its leaves (Figure 2A). Similarly, a high total of phenolic content (90–110 mg 100 g−1) has been reported in other corn salad cultivars as compared with other vegetables used in RTESs, the major individual phenolic in corn salads being chlorogenic acid, followed by diosmetin, rutin (quercetin 3-O-rutinoside), luteolin, kaempferol 3-O-rutinoside and genistein, which were found at very low concentrations [47,48]. Phenolic content remained without significant changes in corn salads during the whole storage period, while significant increases (p < 0.05) occurred in radicchio, from 64.71 ± 3.87 mg 100 g−1 FW at day 0 to 95.89 ± 7.13 mg 100 g−1 FW at day 11 (Figure 2A). On the contrary, the total phenolic concentration decreased significantly (p < 0.05) in green parts of escarole leaves, from day 4 to day 8 (before the expiration date), while no significant changes occurred in white escarole leaves (Figure 2A).
Corn salads were the ingredient with the highest antioxidant activity with values of 175–200 mg 100 g−1 during storage, followed by radicchio, in which antioxidant activity at day 0 was 62.08 ± 3.71 mg 100 g−1 and increased significantly (p < 0.05) until day 7 (80.2 ± 4.77 mg 100 g−1) decreasing afterwards. Finally, escarole showed the lowest values of antioxidant activity, being significantly (p < 0.05) lower in white than in green portions of leaves and showing a decreasing trend during storage (Figure 2B). A high correlation was found between total phenolic content and antioxidant activity by taking into account data of all ingredients and sampling dates (y = 0.676x + 6.45; r2 = 0.849). Thus, in general, phenolic compounds could be considered as the major factor responsible for antioxidant properties and beneficial health effects of RTES consumption, as has been reported for a wide range of fresh vegetables [22,23,24,49], although in some RTESs, carotenoids and ascorbic acid also make a high contribution to the antioxidant capacity of the produce [47]. However, it is worth noting that differences between corn salads and radicchio in total phenolic content were lower than differences in antioxidant activity, especially at the last sampling dates. These results could be explained by the higher ascorbic acid concentration reported in canon leaves [48,49] than in radicchio [45,50], which were 20–38 and 8–20 mg 100 g−1, depending on cultivars and growing conditions. Nowadays, it has been proved that the success of any technological food depends on consumer acceptance and that consumers demand high-quality products with added health properties [51,52]. Thus, since cannons are an ingredient with high phenolic content and antioxidant activity, it could be interesting to increase the relative proportion of corn salads in RTESs and provide information to consumers in package labels about this enhanced functional property.

3.2.3. Sensorial Quality of the Different RTES Ingredients

Browning was detected at day 7 (a day after expiration date) in all the RTES ingredients, mainly in the white leaves of escarole and radicchio, 23.33 ± 5.53% and 15 ± 5%, respectively, which increased until the last sampling date, reaching values of 47 and 22%, respectively, while browning was very low (less than 3%) in corn salads and green escarole leaves (Figure 3A). Accordingly, Mazzocco et al. [42] reported that browning started after seven days of storage in domestic refrigerators and was attributed to chlorophyll degradation and phenolic compound oxidation by polyphenol oxidase activity, which was induced by cutting vegetable products during processing operations. The percentage of cut leaves showing visible dehydration symptoms increased during storage, reaching the highest values in corn salads (≈60%) and the lowest in green escarole leaves (≈35%) at the last sampling date (Figure 3B). Rotten areas started to be visible at day 7, affecting ≈6% of the cut leaves of all ingredients and remained without significant changes until the last sampling date except for corn salads, in which this percentage increased up to ≈10% (Figure 3C). Finally, general appearance decreased after day 4 in all ingredients of RTESs, although all of them had scored higher than six at day 7 (8.33 ± 1.00, 7.56 ± 0.73, 6.67 ± 1.41 and 6.67 ± 1.94 for green escarole, corn salads, radicchio and white escarole, respectively), still over the limit of acceptance for consumption (Figure 3D). Accordingly, Preti and Vinci [25] reported losses of general appearance in ready-to-eat salads after four days of storage.

4. Conclusions

This survey was performed with 296 participants, 55.7% female and 44.3% male, most of them (75%) usual consumers once–twice a week of RTESs with mixed ingredients. The most important reason for not consuming RTESs was the use of plastic packages for environmental concerns. Consumers of RTESs gave more importance to the expiration date and visual quality properties when buying them than when consuming after storage in a domestic refrigerator at home. The microbiological quality of RTESs was maintained at acceptable and safe levels even after the expiration date. Finally, the content of bioactive compounds, such as total phenolics and antioxidant activity, was generally maintained and even increased during RTES storage in a domestic refrigerator, with the higher values being found in corn salads. Thus, quality properties of RTESs composed of mixed ingredients were maintained in domestic refrigerators even after the expiration date, and these food products could be considered healthy due to their high content of bioactive compounds, which would be enhanced by increasing the relative proportion of corn salads.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/su14063473/s1, Questionnaire is in Supplementary File.

Author Contributions

M.T.P. conceived and designed the work in association with other authors. J.M.L.-M. and J.M.V. performed the survey and the analytical determinations. M.T.P. and M.S. analysed the data and wrote the manuscript. All authors have read and agreed to the published version of the manuscript.

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. University Miguel Hernández (UMH) has funded the laboratory equipment and publishing fees.

Institutional Review Board Statement

This study was conducted according to the guidelines laid down in the Declaration of Helsinki and all procedures involving research study participants were approved by the Ethics Committee of the University Miguel Hernández (reference DBA.MPP.01.21).

Informed Consent Statement

Informed consent was obtained from all participants involved in the survey.

Data Availability Statement

Not applicable.

Acknowledgments

We are grateful to participants in the survey for answering the questionnaire, to University Miguel Hernández for facilities and publishing fees and to Anthony Nicolson for editing and correcting the manuscript.

Conflicts of Interest

The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.

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Figure 1. Mesophilic aerobic, psychrophilic aerobic and mould and yeast counts in ready-to-eat salads (RTESs) during storage in domestic refrigerator. Day 0 was the date of buying when RTESs arrived at the supermarket. Data are the mean ± SE. LSD value shows significant differences at p < 0.05.
Figure 1. Mesophilic aerobic, psychrophilic aerobic and mould and yeast counts in ready-to-eat salads (RTESs) during storage in domestic refrigerator. Day 0 was the date of buying when RTESs arrived at the supermarket. Data are the mean ± SE. LSD value shows significant differences at p < 0.05.
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Figure 2. Total phenolic content as mg gallic acid equivalent (A) and total antioxidant activity as mg L-ascorbic acid equivalent (B) in each one of the ingredients of ready-to-eat salads (RTESs) during storage in domestic refrigerator. Day 0 was the date of buying when RTESs arrived at the supermarket. Data are the mean ± SE. LSD value shows significant differences at p < 0.05.
Figure 2. Total phenolic content as mg gallic acid equivalent (A) and total antioxidant activity as mg L-ascorbic acid equivalent (B) in each one of the ingredients of ready-to-eat salads (RTESs) during storage in domestic refrigerator. Day 0 was the date of buying when RTESs arrived at the supermarket. Data are the mean ± SE. LSD value shows significant differences at p < 0.05.
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Figure 3. Brown leaves (A), dehydrated leaves (B), leaves with rotten areas (C) and general appearance of ready-to-eat salads (RTESs) during storage in domestic refrigerator. (D) Day 0 was the date of buying when RTESs arrived at the supermarket. Data are the mean ± SE. LSD value shows significant differences at p < 0.05.
Figure 3. Brown leaves (A), dehydrated leaves (B), leaves with rotten areas (C) and general appearance of ready-to-eat salads (RTESs) during storage in domestic refrigerator. (D) Day 0 was the date of buying when RTESs arrived at the supermarket. Data are the mean ± SE. LSD value shows significant differences at p < 0.05.
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Table
Table 1. Characteristics of the participants in the survey (n = 297).
Table 1. Characteristics of the participants in the survey (n = 297).
CharacteristicPercentage (%)
Gender
Female55.7
Male44.3
Age
18–246.8
25–3515.9
36–5044
51–6531
Older than 652.3
Educational level
Primary school2.7
Secondary school7.8
Technical education12.5
University77
Marital status
Couples with children53.6
Childless couples21.2
Single-parent family6
Single without children19.2
Employment
Student7.1
Employed (permanently)73.6
Employed (temporary)12
Unemployed5.1
Pensioner2.2
Consumer of minimally processed salads
Consumer75.7
Non consumer24.3
Table
Table 2. Level of importance (none, little, medium, quite, very much) that consumers give to different aspects. Answer to the question: Why are you not a consumer of minimally processed salads? (n = 69).
Table 2. Level of importance (none, little, medium, quite, very much) that consumers give to different aspects. Answer to the question: Why are you not a consumer of minimally processed salads? (n = 69).
AnswerNone (%)Little (%)Medium (%)Quite (%)Very Much (%)
Price (they are very expensive)14.527.531.911.614.5
Fresh produce is healthier 13.121.714.527.523.2
I don't like their appearance21.733.321.714.58.8
The use of plastics in packaging7.213.118.823.237.7
Table
Table 3. Frequency of consumption and type of fresh-cut salads that consumers usually buy (n = 224).
Table 3. Frequency of consumption and type of fresh-cut salads that consumers usually buy (n = 224).
CharacteristicPercentage (%)
Frequency of consumption
Less than 1 time/month8.5
1–2 times/month28.5
1–2 times/week40
3–4 times/week17
Daily6
Type of salad you eat
Single ingredient5.5
Various ingredients56.5
Both types38
Table
Table 4. Level of importance (none, little, medium, quite, a lot) that consumers gave to different aspects of RTESs at purchasing and consuming times (n = 224).
Table 4. Level of importance (none, little, medium, quite, a lot) that consumers gave to different aspects of RTESs at purchasing and consuming times (n = 224).
Answer to the Consumer of Minimally Processed SaladsNone (%)Little (%)Medium (%)Quite (%)Very Much (%)
Time of purchase of the fresh-cut salads
Variety of ingredients2.711.620.140.225.4
Price6.72032.629.913.8
Accompaniment of dressing and cutlery37.531.714.38.58.0
Amount of plastic it contains9.818.329.916.125.9
Bioactive compounds5.813.822.325.931.3
Date of expiration1.36.38.926.353.6
Presence of exudates2.78.08.519.261.6
Presence of brown leaves2.36.76.318.366.5
Presence of dehydrated leaves1.85.83.118.870.5
Time to consume the fresh-cut salad after several days stored in the refrigerator
Date of expiration3.110.719.226.340.6
Presence of strange odours0.95.44.018.371.4
Presence of exudates1.85.47.119.665.2
Presence of brown leaves0.95.810.32558.0
Presence of dehydrated leaves1.36.37.62559.8
Table
Table 5. Question addressed to consumers about whether they would buy/consume fresh-cut salads if any of the assessed aspects failed (n = 224).
Table 5. Question addressed to consumers about whether they would buy/consume fresh-cut salads if any of the assessed aspects failed (n = 224).
Answer to the QuestionPercentage (%)
Would you buy the salad if any of the valued aspects failed?
Yes. It depends on the price1
Yes. It depends on the aspect9
Yes. It depends on the expiration date1.7
Yes. It depends on the price, the appearance and the expiration date23.9
Never64.4
Would you eat the salad if any of the valued aspects failed?
Yes. I don't want to waste food4.3
Yes. It depends on the expiration date4.3
Yes. It depends on the appearance of the product41.1
Never50.3
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Lorente-Mento, J.M.; Valverde, J.M.; Serrano, M.; Pretel, M.T. Fresh-Cut Salads: Consumer Acceptance and Quality Parameter Evolution during Storage in Domestic Refrigerators. Sustainability 2022, 14, 3473. https://doi.org/10.3390/su14063473

AMA Style

Lorente-Mento JM, Valverde JM, Serrano M, Pretel MT. Fresh-Cut Salads: Consumer Acceptance and Quality Parameter Evolution during Storage in Domestic Refrigerators. Sustainability. 2022; 14(6):3473. https://doi.org/10.3390/su14063473

Chicago/Turabian Style

Lorente-Mento, José M., Juan M. Valverde, María Serrano, and María T. Pretel. 2022. "Fresh-Cut Salads: Consumer Acceptance and Quality Parameter Evolution during Storage in Domestic Refrigerators" Sustainability 14, no. 6: 3473. https://doi.org/10.3390/su14063473

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