Editorial

4 pages, 202 KiB

Open AccessEditorial

Advances in Postharvest Preservation and Quality of Fruits and Vegetables

by Juan Luis Valenzuela

Foods 2023, 12(9), 1830; https://doi.org/10.3390/foods12091830 - 28 Apr 2023

Cited by 2 | Viewed by 2999

Numerous agricultural regions face the daunting task of providing high-quality fresh fruits and vegetables to increasingly competitive markets [...] Full article

(This article belongs to the Special Issue Advances in Post-harvest Preservation and Quality of Fruits and Vegetables)

Research

Jump to: Editorial, Review

21 pages, 3705 KiB

Open AccessArticle

The Relationships between Waxes and Storage Quality Indexes of Fruits of Three Plum Cultivars

by Shouliang Zhu, Shian Huang, Xin Lin, Xuan Wan, Qin Zhang, Junsen Peng, Dengcan Luo, Yun Zhang and Xiaoqing Dong

Foods 2023, 12(8), 1717; https://doi.org/10.3390/foods12081717 - 20 Apr 2023

Cited by 3 | Viewed by 1202

Abstract

In the present study, the cuticular wax morphology, composition and the relationship with storage quality in three plum cultivars of Prunus salicina ‘Kongxin’ (KXL), Prunus salicina ‘Fengtang’ (FTL) and Prunus salicina ‘Cuihong’ (CHL) were investigated during storage at room temperature of 25 ± [...] Read more.

In the present study, the cuticular wax morphology, composition and the relationship with storage quality in three plum cultivars of Prunus salicina ‘Kongxin’ (KXL), Prunus salicina ‘Fengtang’ (FTL) and Prunus salicina ‘Cuihong’ (CHL) were investigated during storage at room temperature of 25 ± 1 °C. The results illustrated that the highest cuticular wax concentration was discovered in KXL, followed by FTL and the lowest in CHL. The fruit wax composition of the three plum cultivars was similar and principally composed of alkanes, alcohols, fatty acids, ketones, aldehydes, esters, triterpenes and olefins. Alcohols, alkanes and triterpenes were the dominant fruit wax compounds of the three plum cultivars. After storage for 20 d at room temperature, the variation of cuticular wax crystal structure and composition showed significant cultivar-associated differences. The total wax content decreased for FTL and CHL and increased for KXL, and the wax crystal degraded and melted together over time. The higher contents of the main components in the three plum cultivars were nonacosane, 1-triacontanol, 1-heneicosanol, nonacosan-10-one, octacosanal, ursolic aldehyde and oleic acid. Alcohols, triterpenes, fatty acids and aldehydes were most dramatically correlated with the softening of fruit and storage quality, and alkanes, esters and olefins were most significantly correlated with the water loss. Nonacosane and ursolic aldehyde can enhance the water retention of fruit. Overall, this study will provide a theoretical reference for the further precise development of edible plum fruit wax. Full article

(This article belongs to the Special Issue Advances in Post-harvest Preservation and Quality of Fruits and Vegetables)

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13 pages, 2622 KiB

Open AccessFeature PaperArticle

Use of Sub-Atmospheric Pressure Storage to Improve the Quality and Shelf-Life of Marmande Tomatoes cv. Rojito

by María del Carmen Salas-Sanjuán, María del Mar Rebolloso, Fernando del Moral and Juan Luis Valenzuela

Foods 2023, 12(6), 1197; https://doi.org/10.3390/foods12061197 - 12 Mar 2023

Cited by 3 | Viewed by 1735

Abstract

In this study, the feasibility of storing Marmande tomatoes (Solanum lycopersicum, cv Rojito) under hypobaric conditions was evaluated. The fruits were sorted into four lots of 72 fruits each. One lot was considered as a control, and the fruits were kept in [...] Read more.

In this study, the feasibility of storing Marmande tomatoes (Solanum lycopersicum, cv Rojito) under hypobaric conditions was evaluated. The fruits were sorted into four lots of 72 fruits each. One lot was considered as a control, and the fruits were kept in the open box, while the fruits of the rest of the three remaining lots were enclosed in airtight containers and subjected to 101, 75 and 50 Kpa, respectively. Control fruits and airtight containers were kept at room temperature, and every three days from the beginning of the experiment the following main quality parameters were analysed: ethylene production rate, firmness, colour, total solids content, ascorbic acid, total phenolics and pigments, as well as a sensory analysis carried out by panellists. The results show that sub-atmospheric storage led a reduction in ethylene production, which was associated with a delay in ripening. The differences in the evolution of pigments were very significant, while a large degradation of chlorophylls was observed in the control fruits and in those kept at 101 kPa, in the fruits kept at 75 kPa and 50 kPa the degradation was much slower. In relation to carotenoid pigments, it was observed that sub-atmospheric treatments delayed their appearance compared to control and 101 kPa fruits. In relation to other quality parameters, it was found that control fruit and fruit held at 101 kPa softened more rapidly than fruit under sub-atmospheric conditions, whose loss of firmness was more gradual with differences found only at 9 and 12 days of storage with respect to fruit firmness at harvest. The appearance of these fruits was evaluated with the same score as at the time of harvesting, during 9 of the 12 days of the experiment, then a positive effect of sub-atmospheric treatments was also found in the sensory analysis. The results suggest that sub-atmospheric storage could be a suitable method of increasing the shelf-life of fruits. Full article

(This article belongs to the Special Issue Advances in Post-harvest Preservation and Quality of Fruits and Vegetables)

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14 pages, 4821 KiB

Open AccessArticle

Magnolol Loaded on Carboxymethyl Chitosan Particles Improved the Antimicrobial Resistance and Storability of Kiwifruits

by Feixu Mo, Wenzhi Li, Youhua Long, Rongyu Li, Yi Ding and Ming Li

Foods 2023, 12(6), 1149; https://doi.org/10.3390/foods12061149 - 08 Mar 2023

Cited by 2 | Viewed by 1220

Abstract

Magnolol is a natural compound extracted from the traditional Chinese medicine Magnolia officinalis, which exhibits antimicrobial properties. However, magnolol is insoluble in water and consists of a phenolic hydroxyl group, which is volatile; these factors hinder its application. In this study, a [...] Read more.

Magnolol is a natural compound extracted from the traditional Chinese medicine Magnolia officinalis, which exhibits antimicrobial properties. However, magnolol is insoluble in water and consists of a phenolic hydroxyl group, which is volatile; these factors hinder its application. In this study, a safe and environmentally friendly method to improve the microbial resistance and storability of harvested fruits is developed using the water-soluble carrier carboxymethyl chitosan (CMCS) and magnolol. Magnolol was loaded on CMCS particles to form Magnolol@CMCS antimicrobial particles, a preservation coating agent. Magnolol@CMCS particles effectively solved the problems of water insolubility and agglomeration of magnolol and reduced the size distribution D50 value of magnolol from 0.749 to 0.213 μm. Magnolol@CMCS particles showed greater toxicity against Staphylococcus aureus, Escherichia coli, and Botryosphaeria dothidea than that of magnolol alone, with effective medium concentration (EC₅₀) values of 0.9408, 142.4144, and 8.8028 μg/mL, respectively. Kiwifruit treated with the Magnolol@CMCS solution showed delayed changes in fruit hardness and soluble solid and dry matter contents and significantly higher ascorbic acid (vitamin C) and soluble total sugar contents and sugar:acid ratios compared with that of the control fruit. In addition, no disease spots were observed on fruit treated with the Magnolol@CMCS solution within 7 days after inoculation with B. dothidea. In conclusion, Magnolol@CMCS particles showed antimicrobial activity on harvested fruits, effectively delayed the hardness and nutritional changes of fruits during storage, and improved the storability of kiwifruit. Full article

(This article belongs to the Special Issue Advances in Post-harvest Preservation and Quality of Fruits and Vegetables)

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14 pages, 6268 KiB

Open AccessArticle

The Effects of Storage Temperature, Light Illumination, and Low-Temperature Plasma on Fruit Rot and Change in Quality of Postharvest Gannan Navel Oranges

by Ying Sun, Yuanyuan Li, Yu Xu, Yali Sang, Siyi Mei, Chaobin Xu, Xingguo Yu, Taoyu Pan, Chen Cheng, Jun Zhang, Yueming Jiang and Zhiqiang Gao

Foods 2022, 11(22), 3707; https://doi.org/10.3390/foods11223707 - 18 Nov 2022

Cited by 6 | Viewed by 2148

Abstract

Gannan navel orange (Citrus sinensis Osbeck cv. Newhall) is an economically important fruit, but postharvest loss occurs easily during storage. In this study, the effects of different temperatures, light illuminations, and low-temperature plasma treatments on the water loss and quality of the [...] Read more.

Gannan navel orange (Citrus sinensis Osbeck cv. Newhall) is an economically important fruit, but postharvest loss occurs easily during storage. In this study, the effects of different temperatures, light illuminations, and low-temperature plasma treatments on the water loss and quality of the Gannan navel orange were investigated. The fruit began to rot after 90 d of storage at 5 °C and 20–45 d at 26 °C. Navel oranges stored at 26 °C had 7.2-fold and 3.1-fold higher rates of water loss at the early and late storage stages, respectively, as compared with those stored at 5 °C. Storage at 5 °C decreased the contents of total soluble solids at the early storage stage and the contents of titratable acids at the late storage stage, whereas storage at 26 °C decreased the contents of total soluble solids at the late storage stage and the contents of titratable acids at the early storage stage, respectively. Application of low-temperature plasma produced by air ionization for 6 min, or continuous blue or red light illumination significantly inhibited water loss within 7 and 21 d of storage at 22 °C, respectively, but exhibited no significant effect on fruit quality. Furthermore, the low-temperature plasma treatment protected against fruit rot. Thus, treatment with low-temperature plasma followed by storage at a low temperature under continuous red or blue light illumination was of potential value as a green technology for preserving Gannan navel orange during storage. Full article

(This article belongs to the Special Issue Advances in Post-harvest Preservation and Quality of Fruits and Vegetables)

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14 pages, 2547 KiB

Open AccessArticle

Gene Expression Analyses Reveal Mechanisms of Inhibited Yellowing by Applying Selenium-Chitosan on Fresh-Cut Broccoli

by Gang Ren, Yaping Liu, Bing Deng, Yu Wang, Wenyan Lin, Yulei Zhang, Jianbing Di and Jiali Yang

Foods 2022, 11(19), 3123; https://doi.org/10.3390/foods11193123 - 08 Oct 2022

Cited by 4 | Viewed by 1870

Abstract

The yellowing of green broccoli is a phenomenon that indicates a serious deterioration of freshness. The green broccoli has been more popular than the yellow one, with its higher nutritional value. Chitosan coating has been employed in vegetables for green-keeping, owing to its [...] Read more.

The yellowing of green broccoli is a phenomenon that indicates a serious deterioration of freshness. The green broccoli has been more popular than the yellow one, with its higher nutritional value. Chitosan coating has been employed in vegetables for green-keeping, owing to its functions of regulating chlorophyll metabolism and antioxidant defense. Furthermore, selenium was commonly utilized in the pre-harvest of fruit and vegetables as an antioxidant and chlorophyll regulator. However, there have not yet been concerns about the effects of selenium-chitosan on vegetable yellowing. This study first investigated the impact of selenium-chitosan on the quality of fresh-cut broccoli yellowing during storage by analyzing the chromatic aberration and phytochromes. Additionally, then, the gene expression related to chlorophyll metabolism (POR, CAO, HO, CHLI, NYC1), carotenoid metabolism (VDE, CCS, LCYE, ZEP, HYD), and transcription factors (NAC92, ZIPPER, bHLH66, APL, PIF4) were analyzed using the RT-qPCR technique. Test results showed that treatment with selenium-chitosan can slow down the reduction in h° (Hue angle values) and reduce ethylene release rate and respiration intensity. Via the molecular approach, it was further identified that this treatment could inhibit chlorophyll degradation and carotenoid biosynthesis, accompanied by lower expression levels of heme oxygenase (HO), chlorophyllide A oxygenase (CAO), violaxanthin de-epoxidase (VDE), β-carotene 3-hydroxylase (HYD), NAC92, basic leucine zipper (ZIPPER), bHLH66, PIF4 and APL, and higher expression levels of magnesium chelatase subunit I (CHLI) and lycopene ε-cyclase (LCYE) genes. This work can be used to explore the molecular mechanism of selenium-chitosan in inhibiting the yellowing of fresh-cut broccoli. This study will be of great economic importance in marketing and export by increasing the shelf life of fruits and vegetables. Full article

(This article belongs to the Special Issue Advances in Post-harvest Preservation and Quality of Fruits and Vegetables)

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12 pages, 852 KiB

Open AccessArticle

Post-Harvest LED Light Irradiation Affects Firmness, Bioactive Substances, and Amino Acid Compositions in Chili Pepper (Capsicum annum L.)

by Chaochao Liu, Hongjian Wan, Youxin Yang, Qingjing Ye, Guozhi Zhou, Xiaorong Wang, Golam Jalal Ahammed and Yuan Cheng

Foods 2022, 11(17), 2712; https://doi.org/10.3390/foods11172712 - 05 Sep 2022

Cited by 10 | Viewed by 2357

Abstract

Chili pepper is an important vegetable and spice crop with high post-harvest deteriorations in terms of commercial and nutritional quality. Light-emitting diodes (LEDs) are eco-friendly light sources with various light spectra that have been demonstrated to improve the shelf-life of various vegetables by [...] Read more.

Chili pepper is an important vegetable and spice crop with high post-harvest deteriorations in terms of commercial and nutritional quality. Light-emitting diodes (LEDs) are eco-friendly light sources with various light spectra that have been demonstrated to improve the shelf-life of various vegetables by manipulating light quality; however, little is known about their effects on the post-harvest nutritional quality of chili peppers. This study investigated the effects of different LED lightings on the post-harvest firmness and nutritional quality of chili peppers. We found that red and blue light could increase the content of capsaicinoids, whereas white and red light could increase the essential and aromatic amino acid (AA) content in pepper. Nonetheless, the influence of light treatments on AA contents and compositions depends strongly on the pepper genotype, which was reflected by total AA content, single AA content, essential AA ratio, delicious AA ratio, etc., that change under different light treatments. Additionally, light affected fruit firmness and the content of nutrients such as chlorophyll, vitamin C, and total carotenoids, to varying degrees, depending on pepper genotypes. Thus, our findings indicate that LED-light irradiation is an efficient and promising strategy for preserving or improving the post-harvest commercial and nutritional quality of pepper fruit. Full article

(This article belongs to the Special Issue Advances in Post-harvest Preservation and Quality of Fruits and Vegetables)

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18 pages, 2725 KiB

Open AccessArticle

Fruitomics: The Importance of Combining Sensory and Chemical Analyses in Assessing Cold Storage Responses of Six Peach (Prunus persica L. Batsch) Cultivars

by Antonella Muto, Sarah R. Christofides, Tiziana Maria Sirangelo, Lucia Bartella, Carsten Muller, Leonardo Di Donna, Innocenzo Muzzalupo, Leonardo Bruno, Antonio Ferrante, Adriana A. C. Chiappetta, Maria Beatrice Bitonti, Hilary J. Rogers and Natasha Damiana Spadafora

Foods 2022, 11(17), 2554; https://doi.org/10.3390/foods11172554 - 24 Aug 2022

Cited by 6 | Viewed by 2090

Abstract

Cold storage is used to extend peach commercial life, but can affect quality. Quality changes are assessed through the content of nutritionally relevant compounds, aroma, physical characters and/or sensorially. Here, six peach and nectarine cultivars were sampled at commercial harvest and after 7 [...] Read more.

Cold storage is used to extend peach commercial life, but can affect quality. Quality changes are assessed through the content of nutritionally relevant compounds, aroma, physical characters and/or sensorially. Here, six peach and nectarine cultivars were sampled at commercial harvest and after 7 days of 1 °C storage. A trained panel was used to evaluate sensorial characters, while carotenoids, phenolics, vitamin C, total sugars, and qualitative traits including firmness, titrable acidity and soluble solid content were integrated with volatile organic compound (VOC) analysis previously reported. The different analyses reveal interesting patterns of correlation, and the six cultivars responded differently to cold storage. Sensory parameters were correlated with 64 VOCs and seven intrinsic characters. Acidity, firmness, and 10 VOCs were strongly negatively correlated with harmony and sweetness, but positively correlated with bitterness, astringency, and crunchiness. In contrast, Brix, b-carotene, and six VOCs were positively correlated with harmony and sweetness. Full article

(This article belongs to the Special Issue Advances in Post-harvest Preservation and Quality of Fruits and Vegetables)

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16 pages, 3289 KiB

Open AccessArticle

Pulsed Electric Field and Freeze-Thawing Pretreatments for Sugar Uptake Modulation during Osmotic Dehydration of Mango

by Pingdwendé Assana Zongo, Seddik Khalloufi, Sergey Mikhaylin and Cristina Ratti

Foods 2022, 11(17), 2551; https://doi.org/10.3390/foods11172551 - 23 Aug 2022

Cited by 7 | Viewed by 1666

Abstract

Osmotic dehydration kinetics depends on food tissue microstructure; thus, modulation of mango porosity could help selectively enhance water removal over sugar gain. In this present study, pretreatments of freeze-thawing (freezing at −36 °C for 2 weeks and thawing at 4 °C for 24 [...] Read more.

Osmotic dehydration kinetics depends on food tissue microstructure; thus, modulation of mango porosity could help selectively enhance water removal over sugar gain. In this present study, pretreatments of freeze-thawing (freezing at −36 °C for 2 weeks and thawing at 4 °C for 24 h) and pulsed electric field (1 kV/cm, 10 and 30 pulse numbers), were applied to mango 1 cm-thickness slices prior to osmotic dehydration conducted at 40 °C for 4 h. Three different 60 °Brix agave syrup solutions with or without added polysaccharides (inulin or xanthan gum) were used in the osmotic dehydration operation. Water loss (WL), sugar gain (SG) and microstructure images were used to compare the effects of pretreatments on mango osmotic dehydration efficiency. Results indicated that pulsed electric field (PEF) pretreatment increased slightly WL during osmotic dehydration, contrary to freeze-thawing (F-T), which for most cases led to a decrease. As for solids uptake, due to higher damage induced by F-T to mango tissue, SG was higher than for fresh and PEF pretreated mangoes. Using xanthan gum as additive to agave syrup solution, helped to decrease sugar uptake in frozen-thawed mango due to an increase in solution viscosity. A similar WL/SG ratio was obtained with frozen-thawed mango in solution with xanthan gum. Therefore, in the case of frozen-thawed mango, it is recommended to use an osmotic solution with high viscosity to obtain low sugar uptake in the final product. The novelty of this contribution is twofold: (i) using pretreatments (F-T or PEF) to minimize sugar uptake during osmotic dehydration, and (ii) using agave syrup with added polysaccharides to enrich final product with inulin. Full article

(This article belongs to the Special Issue Advances in Post-harvest Preservation and Quality of Fruits and Vegetables)

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12 pages, 1733 KiB

Open AccessArticle

Effect of Gaseous Citral on Table Grapes Contaminated by Rhizopus oryzae ITEM 18876

by Laura Quintieri, Francesco Fancello, Leonardo Caputo, Andrea Sorrentino, Severino Zara, Vincenzo Lippolis, Salvatore Cervellieri, Francesca Fanelli, Antonia Corvino, Bernardo Pace and Maria Cefola

Foods 2022, 11(16), 2478; https://doi.org/10.3390/foods11162478 - 17 Aug 2022

Cited by 4 | Viewed by 1906

Abstract

Rhizopus oryzae is responsible for rapidly producing a deliquescent appearance in grape berries, generally favoured by cold chain interruptions. To counteract fruit spoilage and to meet consumer acceptance, innovative strategies based on the application of natural compounds are ongoing. Due to their biological [...] Read more.

Rhizopus oryzae is responsible for rapidly producing a deliquescent appearance in grape berries, generally favoured by cold chain interruptions. To counteract fruit spoilage and to meet consumer acceptance, innovative strategies based on the application of natural compounds are ongoing. Due to their biological activities, including antimicrobial ones, natural flavour compounds extend the shelf life and improve the nutritional value as well as the organoleptic properties of foods. Thus, in this work, the application of the antimicrobial citral, a flavor component of monoterpenes identified in plant and fruit essential oils, was developed and validated against one spoiler of R. oryzae. Citral, as pure compound, was first investigated in vitro against R. oryzae ITEM 18876; then, concentrations equal to the minimal inhibitory concentration (MIC) and 4-fold MIC (4MIC) value were applied on the table grape cv Italia infected with this strain and stored. The MIC value was equal to 0.0125 μL/cm³; both citral concentrations (0.0125 and 0.05 µL/cm³) were effective in counteracting the microbial decay of infected table grapes over the storage period. The HS-SPME/GC-MS method showed citral persistence in the head space of plastic trays with the infected samples; as expected, a higher content of citral isomers was found in the sample treated with 4MIC value. In conclusion, citral revealed its efficacy to counteract the onset of soft rot by R. oryzae ITEM 18876 under storage conditions. Thus, it could be successfully exploited to develop an active packaging or natural preservatives to extend table grape shelf life without affecting its quality and sensory characteristics, whilst also satisfying the consumer demand for natural preservative agents. Full article

(This article belongs to the Special Issue Advances in Post-harvest Preservation and Quality of Fruits and Vegetables)

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11 pages, 3620 KiB

Open AccessArticle

Research on Damage Properties of Apples Based on Static Compression Combined with the Finite Element Method

by Xiaopeng Liu, Zhentao Cao, Liu Yang, Huan Chen and Yonglin Zhang

Foods 2022, 11(13), 1851; https://doi.org/10.3390/foods11131851 - 23 Jun 2022

Cited by 6 | Viewed by 1893

Abstract

Apples are easily damaged during transportation due to extrusion and collision, resulting in structural damage and deterioration. To better understand apples’ mechanical–structural damage behavior, a texture analyzer platform combined with in situ observation was established. The effects of extrusion distance, speed, working temperature, [...] Read more.

Apples are easily damaged during transportation due to extrusion and collision, resulting in structural damage and deterioration. To better understand apples’ mechanical–structural damage behavior, a texture analyzer platform combined with in situ observation was established. The effects of extrusion distance, speed, working temperature, and typical kinds of apple were considered for damage mechanisms. Apple damage was analyzed via the finite element method (FEM). The results indicated that the apple extrusion behavior can be divided into elastic interaction and plastic damage. Compression displacement effects were obviously significant in terms of structural damage, and apple samples were in an elastic stage with displacement of less than 2.3 mm, and no structural damage. The peak force energy-displacement mathematical model was established, showing an “s” shape and upward parabolic shape. The critical compression energy was around 100N·mm during elastic interaction. The damaged area was positively correlated with the compression energy. The FEM simulation results were consistent with the damage distribution of apples. The effects of speed on the three apple types were different. Red Fuji apples with a bruised area were not sensitive to pressure speed. The effect on the crack forming of Ralls apples was significant. Golden Delicious apples with a bruised area and crack formation showed an intermediate effect. The peak force–temperature fitting curve showed a downward parabolic shape and an R² determination factor of 0.99982. Apple squeeze damage mechanisms provide theoretical guidance for apple damage control. Full article

(This article belongs to the Special Issue Advances in Post-harvest Preservation and Quality of Fruits and Vegetables)

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23 pages, 2388 KiB

Open AccessArticle

Prediction of Date Fruit Quality Attributes during Cold Storage Based on Their Electrical Properties Using Artificial Neural Networks Models

by Maged Mohammed, Muhammad Munir and Aljazi Aljabr

Foods 2022, 11(11), 1666; https://doi.org/10.3390/foods11111666 - 06 Jun 2022

Cited by 26 | Viewed by 3117

Abstract

Evaluating and predicting date fruit quality during cold storage is critical for ensuring a steady supply of high-quality fruits to meet market demands. The traditional destructive methods take time in the laboratory, and the results are based on one specific parameter being tested. [...] Read more.

Evaluating and predicting date fruit quality during cold storage is critical for ensuring a steady supply of high-quality fruits to meet market demands. The traditional destructive methods take time in the laboratory, and the results are based on one specific parameter being tested. Modern modeling techniques, such as Machine Learning (ML) algorithms, offer unique benefits in nondestructive methods for food safety detection and predicting quality attributes. In addition, the electrical properties of agricultural products provide crucial information about the interior structures of biological tissues and their physicochemical status. Therefore, this study aimed to use an alternative approach to predict physicochemical properties, i.e., the pH, total soluble solids (TSS), water activity (a_w), and moisture content (MC) of date fruits (Tamar), during cold storage based on their electrical properties using Artificial Neural Networks (ANNs), which is the most popular ML technique. Ten date fruit cultivars were studied to collect data for the targeted parameters at different cold storage times (0, 2, 4, and 6 months) to train and test the ANNs models. The electrical properties of the date fruits were measured using a high-precision LCR (inductance, capacitance, and resistance) meter from 10 Hz to 100 kHz. The ANNs models were compared with a Multiple Linear Regression (MLR) at all testing frequencies of the electrical properties. The MLR models were less accurate than ANNs models in predicting fruit pH and had low performance and weak predictive ability for the TSS, a_w, and MC at all testing frequencies. The optimal ANNs prediction model consisted of the input layer with 14 neurons, one hidden layer with 15 neurons, and the output layer with 4 neurons, which was determined depending on the measurements of the electrical properties at a 10 kHz testing frequency. This optimal ANNs model was able to predict the pH with R² = 0.938 and RMSE = 0.121, TSS with R² = 0.954 and RMSE = 2.946, a_w with R² = 0.876 and RMSE = 0.020, and MC with R² = 0.855 and RMSE = 0.803 b by using the measured electrical properties. The developed ANNs model is a powerful tool for predicting fruit quality attributes after learning from the experimental measurement parameters. It can be suggested to efficiently predict the pH, total soluble solids, water activity, and moisture content of date fruits based on their electrical properties at 10 kHz. Full article

(This article belongs to the Special Issue Advances in Post-harvest Preservation and Quality of Fruits and Vegetables)

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19 pages, 1337 KiB

Open AccessArticle

Storage Stability and Consumer Acceptability of Dried Apple: Impact of Citric Acid, Potassium Sorbate and Moringa oleifera Leaf Extract Powder

by Washiela Arendse and Victoria Jideani

Foods 2022, 11(7), 984; https://doi.org/10.3390/foods11070984 - 28 Mar 2022

Cited by 3 | Viewed by 1975

Abstract

The effects of a dipping solution containing 2.0% citric acid (CA) and 0.1% Moringa oleifera leaf extract powder (MOLEP) (CMO) and another dipping solution with CA at 2.0%, MOLEP at 0.1% and potassium sorbate (PS) at 0.2% (CMOP) on the storage stability over [...] Read more.

The effects of a dipping solution containing 2.0% citric acid (CA) and 0.1% Moringa oleifera leaf extract powder (MOLEP) (CMO) and another dipping solution with CA at 2.0%, MOLEP at 0.1% and potassium sorbate (PS) at 0.2% (CMOP) on the storage stability over 3 months and consumer acceptability of dried apple slices were evaluated. Microbiological testing (osmophilic yeast, Escherichia coli and yeast and moulds) and total acidity testing were performed and physical tests, namely moisture analysis, water activity (A_w), texture analysis and colour were performed at day 0, day 60 and day 120. Moisture increased over the shelf-life period, which affected the extensibility of the pre-treated dried sliced apples negatively. The CMO pre-treatment was effective in reducing browning and inhibiting microbial growth on the dried apple slices over the storage period. A consumer acceptability test was performed using the nine-point hedonic scale. The dried sliced apples pre-treated with the 2% CA and 0.1% MOLEP powder water solution were acceptable to consumers with regards to colour, texture and taste. Full article

(This article belongs to the Special Issue Advances in Post-harvest Preservation and Quality of Fruits and Vegetables)

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Review

Jump to: Editorial, Research

28 pages, 4369 KiB

Open AccessReview

Advances in the Role and Mechanisms of Essential Oils and Plant Extracts as Natural Preservatives to Extend the Postharvest Shelf Life of Edible Mushrooms

by Yuxi Guo, Xuefeng Chen, Pin Gong, Ruotong Wang, Aoyang Han, Zhenfang Deng, Zhuoya Qi, Hui Long, Jiating Wang, Wenbo Yao, Wenjuan Yang, Jing Wang and Nan Li

Foods 2023, 12(4), 801; https://doi.org/10.3390/foods12040801 - 13 Feb 2023

Cited by 16 | Viewed by 3513

Abstract

China has a large variety of edible mushrooms and ranks first in the world in terms of production and variety. Nevertheless, due to their high moisture content and rapid respiration rate, they experience constant quality deterioration, browning of color, loss of moisture, changes [...] Read more.

China has a large variety of edible mushrooms and ranks first in the world in terms of production and variety. Nevertheless, due to their high moisture content and rapid respiration rate, they experience constant quality deterioration, browning of color, loss of moisture, changes in texture, increases in microbial populations, and loss of nutrition and flavor during postharvest storage. Therefore, this paper reviews the effects of essential oils and plant extracts on the preservation of edible mushrooms and summarizes their mechanisms of action to better understand their effects during the storage of mushrooms. The quality degradation process of edible mushrooms is complex and influenced by internal and external factors. Essential oils and plant extracts are considered environmentally friendly preservation methods for better postharvest quality. This review aims to provide a reference for the development of new green and safe preservation and provides research directions for the postharvest processing and product development of edible mushrooms. Full article

(This article belongs to the Special Issue Advances in Post-harvest Preservation and Quality of Fruits and Vegetables)

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