Shelf Life Period Research Articles

FARKLI DOZLARDA UV-C IŞIN UYGULAMALARININ TAZE İNCİRİN HASAT SONRASI KALİTESİ ÜZERİNE ETKİLERİ

The aim of this study was to investigate the effects of 1.5, 3.0 and 4.5 kJ/m2 UV-C illumination doses on the postharvest quality of fresh fig (cv. Bursa Siyahi). For this purpose, fruit were stored at 0 ºC temperature with 90-95% humidity for 21 days and some fruits were kept at 20 °C for 3 days to simulate a period of shelf-life. UV-C treatments did not affect fruit firmness, total soluble solids, and titratable acidity content during cold storage and shelf-life. On the other hand, UV-C doses increased total phenolic content and antioxidant activity compared to control. In both storage conditions, 3.0 and 4.5 kJ/m2 UV-C doses were found to be more effective to control unmarketable fruit rate. In conclusion, a 4.5 kJ/m2 UV-C illumination dose can be effective in maintaining the postharvest quality of fresh fig fruit harvested at a 2/3 maturity stage.

Chlorophyll breakdown during fruit ripening: Qualitative analysis of phyllobilins in the peel of apples (Malus domestica Borkh.) cv. ‘Gala’ during different shelf life stages

Chlorophyll (Chl) degradation is an important process of fruit ripening, mediated by the pheophorbide a oxygenase/phyllobilin (PaO/PB) pathway. Chl is catabolized to linear tetrapyrrolic phyllobilins that resemble the bile pigments. Determining the optimal harvest date is of pivotal importance for the fruit industry. Among the physiological changes at the onset of ripening and during shelf life, the breakdown of Chl appears as a promising indicator for fruit maturity. In addition, PBs are a frequently overlooked component of the human diet with antioxidant and antiproliferative activities. However, their relevance for a healthy diet and their potential as ripening indicator in fruit cannot be evaluated yet, as details on emergence and composition of PBs in fruit are yet elusive. Using apple (Malus × domestica Borkh.) cv. ‘Gala’ as a model fruit, the Chl content and the emergence and identity of PBs were analyzed during a controlled shelf life period using UV/Vis spectroscopy and ultra-high pressure liquid chromatography coupled to high resolution quadrupole-time of flight-mass spectrometry (UHPLC-Q-TOF-MS). An in-house database with chromatographic and MS data from 51 PBs, revealed ten chlorophyll catabolites, including five NCCs, one YCC, and four DNCCs (including a previously unknown one). PBs were identified with increasing abundance and diversity from the onset of Chl degradation, suggesting a potential role as ripening indicators.

Structural Changes Caused by CO2 or Ethanol Deastringency Treatments in Cold-Stored ‘Giombo’ Persimmon

Persimmon cv. Giombo is astringent at harvest and must be subjected to astringency removal treatment. To date, the most widespread treatment for this variety involves applying ethanol instead of high CO2 concentrations, which is the usual treatment with other varieties. This study aims to evaluate the effect of high CO2 or ethanol concentrations as deastringency treatments on the quality and flesh structure of ’Giombo´ persimmon during cold storage. The deastringency process was faster in the fruit treated with CO2 than with ethanol. One day after treatment, the CO2-treated fruit showed lower soluble tannin levels than those detected sensorially for this variety, while with the ethanol-treated fruit, these values were obtained after 25 storage days plus the shelf-life period. The tannin insolubilisation process was observed by light microscopy. Loss of flesh firmness during storage was more pronounced when fruit were previously treated with ethanol than with CO2. This is closely related to greater parenchyma degradation during storage caused by ethanol treatment, which was observed by a microstructural study by cryo-scanning electron microscopy. Therefore, as deastringency treatment for ‘Giombo’, applying CO2 instead of ethanol treatment is recommended for better fruit quality, especially when fruit are to be cold-stored.

Seasonal differences in softening of early-harvested ‘Royal Gala’ apple fruit are correlated with at-harvest biomarkers indicative of abiotic stress responses

Softening of apple fruit depends on maturity at harvest and a range of orchard and environmental factors. We investigated seasonal effects on ‘Royal Gala’ storage performance independent of maturity and separate from potential orchard effects. In two consecutive seasons, fruit were harvested at four times: very early (H1), early (H2), commercial (H3) and late (H4), and were cold-stored at 0.5 °C for 100 d followed by a shelf-life period. In Year 1, fruit from H1 and H2 softened much less during storage than did fruit from Year 2. Later-harvested fruit (H3 and H4) did not show this seasonal difference and softened similarly in storage. A combined at-harvest transcriptomic and metabolomic study was analysed using mixOmics. Retained firmness in storage was correlated with increased abundance of transcripts indicative of abiotic stress, including those encoding universal stress protein, a drought stress protein, and several heat shock proteins and aquaporins. Greater softening in storage was correlated with higher abundance of fewer and different stress genes, and genes involved in cell wall metabolism. The data suggest that preharvest stresses experienced by the fruit have a profound effect on subsequent softening, at least in early-harvested fruit before ripening-related ethylene becomes the main driver. Ten potential at-harvest biomarkers were identified, including titratable acidity, erythritol and eight transcripts (notably Universal stress protein PHOS32-like and Homeobox leucine zipper protein HAT5-like). These could be useful for predicting the subsequent storage performance of batches of fruit.

Aroma volatiles as predictors of chilling injury development during peach (Prunus persica (L) Batsch) cold storage and subsequent shelf-life

As peaches ripen and deteriorate quickly, cold storage is used to extend their marketability. However, peach cold storage is limited by the development of physiological disorders, such as chilling injury (CI), that express during subsequent shelf-life. The aim of this research was three-fold: first, to determine CI incidence in the melting flesh ‘Red Haven’ peach stored at different temperatures throughout postharvest; secondly, to characterize and compare differences among these fruit with regards to ethylene production rates, physicochemical properties, flesh texture, and aroma volatile profiles; and thirdly, to assess correlations among CI incidence and all the evaluated features, and identify potential key aroma volatile compounds that could predict early stage peach CI development during storage. Fruit were harvested at optimal maturity and stored at 0 °C, 5 °C, and 20 °C for up to 30 d. Evaluations were conducted at harvest (0) and after 1, 3, 5, 15, and 30 d of storage, with and without 3 d shelf-life period. Fruit stored at 5 °C were sensitive to CI displaying impaired capacity for ethylene production, and alterations in fruit textural properties, including reduced expressible juice contents and failure to soften. Chilling-injured fruit decreased accumulation of fruity note lactones, esters and terpenoids (i.e., linalool), and increased production of aldehydes and alcohols, as compared to sound fruit. Furthermore, multivariate regression identified thirteen potential key volatiles that could predict peach CI. These volatiles could be used as markers to discriminate chilling-injured from sound fruit at early stages of development of the disorder, optimizing cold storage and fruit handling practices, while decreasing loss and waste.

Whole Transcriptome Analyses of Apricots and Japanese Plum Fruits after 1-MCP (Ethylene-Inhibitor) and Ethrel (Ethylene-Precursor) Treatments Reveal New Insights into the Physiology of the Ripening Process.

The physiology of Prunus fruit ripening is a complex and not completely understood process. To improve this knowledge, postharvest behavior during the shelf-life period at the transcriptomic level has been studied using high-throughput sequencing analysis (RNA-Seq). Monitoring of fruits has been analyzed after different ethylene regulator treatments, including 1-MCP (ethylene-inhibitor) and Ethrel (ethylene-precursor) in two contrasting selected apricot (Prunus armeniaca L.) and Japanese plum (P. salicina L.) cultivars, ‘Goldrich’ and ‘Santa Rosa’. KEEG and protein–protein interaction network analysis unveiled that the most significant metabolic pathways involved in the ripening process were photosynthesis and plant hormone signal transduction. In addition, previously discovered genes linked to fruit ripening, such as pectinesterase or auxin-responsive protein, have been confirmed as the main genes involved in this process. Genes encoding pectinesterase in the pentose and glucuronate interconversions pathway were the most overexpressed in both species, being upregulated by Ethrel. On the other hand, auxin-responsive protein IAA and aquaporin PIP were both upregulated by 1-MCP in ‘Goldrich’ and ‘Santa Rosa’, respectively. Results also showed the upregulation of chitinase and glutaredoxin 3 after Ethrel treatment in ‘Goldrich’ and ‘Santa Rosa’, respectively, while photosystem I subunit V psaG (photosynthesis) was upregulated after 1-MCP in both species. Furthermore, the overexpression of genes encoding GDP-L-galactose and ferredoxin in the ascorbate and aldarate metabolism and photosynthesis pathways caused by 1-MCP favored antioxidant activity and therefore slowed down the fruit senescence process.

NIR Spectroscopy Assessment of Quality Index of Fermented Milk (Laban) Drink Flavored with Date Syrup during Cold Storage

Fermented milk (laban) with added date syrup can be an excellent candidate for a nutritious drink. Modeling with quality index (Qi) can assist in assessing the quality of the drink’s physiochemical properties. The properties of the laban drink fortified with date syrup were measured and modeled with Qi during shelf life (7 days), and then analyzed with near-infrared spectra (NIR). The aim of this study was to develop a quality index model for the laban drink properties (objective and sensory assessments) and then to predict Qi with a non-destructive measurement of NIR (with partial least-square regression (PLSR) and artificial neural network (ANN) analysis). The results revealed that the developed Qi fits well with measured laban drink properties (viscosity, color, total soluble solids, pH, and sensory assessments during the shelf-life period with R2 = 0.977). The NIR spectrum was efficient to estimate the quality index of the fortified laban drink. It was found that ANN is more appropriate than the PLSR model in estimating the Qi of the Laban drink during cold storage. Thus, non-destructive NIR can predict Qi and can be utilized with great success in the whole chain of production, processing, transportation, storage, and retail market to check the “quality” and “shelf life” of the product.

Microbiological characteristics and applied preservation method of novel ready-to-eat vegetarian spreads and dips

A range of spreads and dips as novel vegetarian ready-to-eat foods are being introduced on the (European) retail market to response to an increasing number of vegetarian’/flexitarian’ consumers and the shift towards plant-based foods consumption. This innovative food group was explored by a product survey (n = 369) in Belgium. The spreads and dips were classified on the presence of main ingredients, the applied preservation mode, the remaining shelf-life period, and the presence of additives. The majority of the products have soybeans or other seeds as the main ingredient, are containing preservatives (e.g. potassium sorbate; E202) and organic acids/acid regulators (e.g. lactic acid; E270 and citric acid; E330) as additives. 45% of the products were marketed under the organic label and 36% of them were indicated as so-called ‘clean label’. From a selection (78 refrigerated and 23 ambient stored products), the physicochemical characteristics (i.e. pH, water activity, and headspace gas composition) were determined as well as the microbiological quality, hygiene, and safety at the moment of purchase and the end of the indicated shelf-life. The analyzed microbiological quality indicators for refrigerated samples demonstrated a psychrotrophic total plate count range of 1.0–9.4 log CFU/g, psychrotrophic lactic acid bacteria range of 1.0–8.8 log CFU/g, yeast and fungi range of 2.0–9.5 log CFU/g and sulfite reducing Clostridia range of 1.0–3.7 log CFU/g. E. coli and coliforms were analyzed as hygiene indicators and solely coliforms were detected on three samples with a maximum count of 3.6 log CFU/g. Listeria monocytogenes was not detected in 10g. Bacillus cereus never exceeded 3.5 log CFU/g. For the ambient stored samples, mesophilic total plate count, mesophilic lactic acid bacteria, yeast and fungi, sulfite reducing Clostridia, B. cereus, B. cereus spores, aerobic spores, and anaerobic spores were determined. Most of the products showed cell counts below the limit of detection (= 1.0 log CFU/g). Only products based on chickpeas, sesame seeds, and other seeds showed cell counts for mesophilic total plate count and aerobic plate count ranging respectively from 1.0 to 4.3 log CFU/g and 1.0 to 5.1 log CFU/g. The research gives insight into the variable microbiological composition and multiple applied preservation modes of this innovative food group of ready-to-eat vegetarian dips and spreads.

Programas comerciais de resfriamento rápido para manga ‘Rosa’: Impactos na qualidade da fruta

ABSTRACT This study aimed to verify the impact of commercial fast-cooling programs on physicochemical quality of ‘Rosa’ mangoes. The study was carried out in a mango packing house in the São Francisco Valley region, Petrolina, PE, Brazil, between August and October 2018. The experiment followed a randomized block design, with three replicates and one pallet per replicate. The treatments were organized in a factorial scheme 2 × 2 × 3 (two fast-cooling times [120 and 240 min] × two storage times x three positions in the pallet). Sixty mangoes were proportionally distributed in three layers at different heights on each of the six pallets. Three pallets were subjected to fast cooling for 120 min and the other three for 240 min. All fruits were stored for 7 and 14 days at 6 °C plus three days of shelf-life at 20 °C. Regardless of cooling program and fruit position in the pallet, the seven-eighths cooling time (SECT) was not attained. The titratable acidity of fruits under 240-min fast cooling decreased significantly after 14 days of cold storage. Fruit weight loss, pulp firmness, dry matter, and soluble solids content were not affected by the fast-cooling programs, both after storage and during shelf-life period. Commercial fast-cooling program can be performed for 120 min.

Optimization of Disinfection Treatment for Shelf Life Extension of Fresh Cut Salad Vegetables

In the present study, disinfectant pre-treatment conditions were optimized for Fresh cut salad vegetables after evaluating bactericidal efficacy of the five different disinfectants viz. Sodium hypochlorite, potassium metabisulfite, citric acid, acetic acid and benzoic acid. Sodium hypochlorite @ 100ppm was selected for disinfectant pretreatment of fresh cut vegetables viz. cucumber, carrot and tomato through physicochemical and microbial analysis. Optimization of pre-treatment conditions viz. temperature, pH and contact time was statistically designed and analyzed using response surface methodology. Numerical optimization of results revealed a temperature of 6.5, 10.0 and 6.5°C; pH 6.0, 7.0 and 7.0; contact time 23.0, 8.0 and 30.0 minutes was found to be optimized for fresh cut cucumber, carrot and tomato disinfectant pretreatment with a desirability level of 94, 94 and 92%, respectively. Shelf life analysis of pre-treated (under optimized conditions) and untreated fresh cut vegetables stored under refrigeration conditions (5-7°C) revealed enhancement in shelf life of treated fresh cut vegetables from 6, 9 and 6 days to 9, 12 and 9 days of fresh cut cucumber, carrot and tomato, respectively. During shelf life period, all physicochemical parameters of pre-treated fresh cut vegetables differed non-significantly along with microbial load under acceptable limits and a good sensory score.

A Study on the Applicability of Wood Preservatives to Wooden Cultural Properties by Aging Treatment

Wooden cultural heritage are exposed to the external environment as they and there are many difficulties in conservation due to their location and size. Among them, biological damage caused by termites or mold consumes a lot of money and time. Select and use wood preservatives to prevent biological damage: Wood preservatives were selected and the worst environmental conditions, temperature 60±3℃, humidity 55±5%, and light intensity of 0.35 W/m2, were subjected to aging treatment to analyze chemical changes. Through the deterioration process, it was confirmed that the change in color difference decreased in the wood preservative treatment compared to the Control group. As a result of measuring the content of the active ingredient contained in the deterioration process of the wood preservative, it was confirmed that the active ingredient content of Gori22 and Bondex Preserve Ⅲ was higher than that of the comparative Wood Keeper A. Through experiments, the shelf life and treatment period can be predicted by measuring the extent to which wood preservatives affect the change of wood specimens during the deterioration process and the content of active ingredients. In conclusion, various wood preservatives were prepared, and the possibility of selectively selecting wood preservatives according to the environment, topography and period was presented as a major evaluation factor.

Exogenous Application of Glycine Betaine Maintains Bioactive Compounds, Antioxidant Activity, and Physicochemical Attributes of Blood Orange Fruit During Prolonged Cold Storage.

Exogenous application of glycine betaine (GB) was evaluated on bioactive compounds, antioxidant activity, and physicochemical attributes of blood orange fruit cv. Moro at 3°C for 90 days. Vacuum infiltration (30 kPa) of GB was applied at 15 and 30 mM for 8 min. Parameters were measured after 1, 30, 60, and 90 days of storage plus 2 days at 20°C to simulate the shelf-life period. GB treatments significantly reduced weight and firmness losses in “Moro” blood orange fruit during cold storage. GB treatment maintained a higher concentration of organic acids (citric, malic, succinic, and oxalic acids) and sugars (sucrose, glucose, and fructose), especially for the higher GB doses (30 mM). During storage, GB treatments enhanced total anthocyanin concentration, total phenolic content, and total antioxidant activity. With respect to enzyme activities, the application of exogenous GB showed increases in catalase (CAT), ascorbate peroxidase, superoxide dismutase, phenylalanine ammonia-lyase, while suppressing the polyphenol oxidase activity. Overall, the most effective treatment was 30 mM GB leading to maintaining bioactive compounds, antioxidant activity, and quality in “Moro” blood orange fruit during long-term storage. The positive results would permit the use of GB as a postharvest tool to maintain the quality attributes of blood orange fruit.

The live bacterial load and microbiota composition of prepacked “ready-to-eat” leafy greens during household conditions, with special reference to E. coli

Ready-to-eat (RTE) leafy greens are popular products that unfortunately have been associated with numerous foodborne illness outbreaks. Since the influence of consumer practices is essential for their quality and safety, the objective of this study was to analyze the microbiota of RTE products throughout shelf life during simulated household conditions. Products from different companies were analyzed in terms of plate counts, and resealed and unopened packages were compared. High bacterial loads were found, up to a total plate count of 9.6 log10 CFU/g, and Enterobacteriaceae plate counts up to 6.0 CFU/g on the expiration date. The effect of consumer practice varied, thus no conclusions regarding resealed or unopened bags could be drawn. The tested products contained opportunistic pathogens, such as Enterobacter homaechei, Hafnia paralvei and Pantoea agglomerans. Amplicon sequencing revealed that the relative abundance of major taxonomic groups changed during shelf life; Pseudomonadaceae and Xanthomonadaceae decreased, while Flavobacteriaceae and Marinomonadaceae inceased. Inoculation with E. coli CCUG 29300T showed that the relative abundance of Escherichia-Shigella was lower on rocket than on other tested leafy greens. Inoculation with E. coli strain 921 indicate growth at the beginning of shelf-life time, while E. coli 731 increases at the end, seemingly able to adapt to cold storage conditions. The high levels of live microorganisms, the detection of opportunistic pathogens, and the ability of E. coli strains to grow at refrigeration temperature raise concerns and indicate that the shelf life may be shortened to achieve a safer product. Due to variations between products, further studies are needed to define how long the shelf-life of these products should be, to ensure a safe product even at the end of the shelf-life period.

The Effect of Combining Post-Harvest Calcium Nanoparticles with a Salicylic Acid Treatment on Cucumber Tissue Breakdown via Enzyme Activity during Shelf Life.

In the present study, an experiment was carried out on the postharvest of cucumber fruit during a 14-day shelf life. The aim was to assess the impact of calcium nanoparticles (CaNPs) blended with different concentrations of salicylic acid (SA) on the shelf life of cucumbers during the seasons of 2018 and 2019. The investigation further monitored the influences of CaNPs-SA on some physical properties of cucumber, including the percentage weight loss, color, and fruit firmness. In addition, chemical properties, such as total soluble solids (SSC%), total acidity (TA%), total soluble sugars, and chlorophyll pigmentation of the fruit skin, were assessed during a 14-day shelf lifeCell wall degradation enzymes (CWEAs) such as polygalacturonase (PG), cel-lulase (CEL), xylanase (XYL), and pectinase (PT) were also researched. In addition, the generation rates of H2O2 and O2•− were calculated, as well as the reduction of DPPH. The lipid peroxidation (malondialdehyde, MDA) and cell membrane permeability (IL%) of cell wall composites were also determined. CaNPs-SA at 2 mM suppressed CWEAs, preserved fruit quality, reduced weight loss throughout the shelf-life period, and reduced the percent leakage value. At this concentration, we also found the lowest levels of MDA and the highest levels of DPPH.

Assessment of samples of common dill (Anethum graveolens L.) by a complex of valuable characteristics

Relevance. Among green and spice crops, dill occupies a special place in the human diet. The crop is widespread and is represented by varieties for various purposes. At present, dill varieties are subject to requirements for morphological (upright form of a bush, large leaf, etc.), phenological characteristics, high productivity of green mass and seeds, and quality. The biochemical composition is one of the main indicators of the quality of dill. Dill contains up to 90% moisture, however, even in that small amount of dry matter found in dill, there are many biologically impor- tant compounds that are necessary for the normal functioning of the human body. Therefore, when creating varieties, these indicators should be taken into account. For this, it is necessary to study and evaluate the parent material and identify promising forms for further breeding work in order to create varieties that have a complex of valuable characteristics. The purpose of the research is to evaluate the collection material of common dill according to a complex of breeding and valuable traits.Materials and Methods. The studies were carried out in the experimental field of the Horticulture Department of the Belarusian State Agricultural Academy in 2019–2020 on soddy-podzolic medium loamy soil. The experiments were performed in compliance with the agrotechnical require- ments for plant care throughout the entire observation period. The objects of research were breeding samples (26) of dill, selected at the Horticulture Department as a result of individual selection from the collection of varieties: Dukat, Sevastopol, Grenadier, Local Bulgarian, Mamut, Uzory, Salut, Almaz, Local Chinese, Alligator, Reshelie, Max, Dalniy, Rzheutsky, a local Krasnodar variety, Hoarfrost.Results. The article presents the results of a study of 26 breeding samples of common dill in 2019–2020. In the course of evaluating the collection material of common dill, highly productive samples were identified at different ripening periods. Differences in the content of dry matter, vitamin C, carotene, low accumulation of nitrates were revealed in the biochemical composition of common dill samples. According to the complex of traits valuable for breeding, samples were selected that can be used in further breeding work to create new varieties characterized by early maturity, high yield and product quality, as well as those having a longer term for the onset of the phase of industrial ripeness and a long period of shelf life.

Postharvest behavior and chilling injury in avocado (Persea americana Mill) fruit cv. Hass treated with 1-methylcyclopropene, ethylene, and intermittent warming

Persea americana, cv. Hass has become an important crop in Colombia due to increased exports to European markets; however, the avocado is a climacteric fruit sensitive to chilling injury, reducing its shelf-life and affecting commercialization abroad. This research aimed to evaluate the effect of 1-methylcyclopropene, ethylene, and intermittent warming on chilling injury and postharvest behavior of avocado cv. Hass. Five treatments were evaluated: Control; Intermittent warming cycles of 4 days at 2 °C + 1 day at 18 °C; Intermittent warming cycles of 7 days at 2 °C + 1 day at 18 °C; 1-methylcyclopropene, and ethylene. The fruits were stored for 29 days at 2 °C and then up to 14 days in the shelf-life period. The intermittent warming treatment 4-days cycles reduced chilling injuries. However, this treatment increased weight loss, respiration, epidermal color index, and electrolyte leakage during the storage period at 2 °C. Intermittent warming showed that Hass avocado fruit ripens faster, regardless of the application of ethylene in the shelf-life period. The results indicated that intermittent warming reduced the chilling injury, the treatment with 1-methylcyclopropene delayed ripening but it is not recommended for avocado cv. Hass when stored at 2 °C because the chilling injury is not reduced.

Impacts of Gum Arabic and Polyvinylpyrrolidone (PVP) with Salicylic Acid on Peach Fruit (Prunus persica) Shelf Life.

Peaches are grown in many Egyptian orchards for local and global fresh market sales. The interior fruit tissue breakdown (IFTB), often resulting in decayed peaches, is a severe problem during marketing. Therefore, to minimize FTB of peaches, in this study, gum arabic (GA) and polyvinylpyrrolidone (PVP) were mixed with different concentrations of salicylic acid (SA) (0, 1, and 2 mM) and were applied as edible coating to extend the shelf life of peach fruits. Mature peaches were selected and harvested when peaches reached total soluble solid content (SSC: 8.5%) and fruit firmness of about 47 N. Fruits were coated and stored at room temperature (26 ± 1 °C and air humidity 51 ± 1%) for 10 days during two seasons: 2020 and 2021. Fruit coated with GA/PVP-SA 2 mM showed a significant (p < 0.05) inhibition in degrading enzyme activities (CWDEs), such as lipoxygenase (LOX), cellulase (CEL), and pectinase (PT), compared to uncoated and coated fruits during the shelf-life period. Hence, cell wall compartments were maintained. Consequently, there was a reduction in browning symptoms in fruits by inhibiting polyphenol oxidase (PPO) and phenylalanine ammonia-lyase (PAL) activities. Thus, the fruit skin browning index showed almost no symptoms. The lipid peroxidation process and ionic permeability declined as well. The result suggests that, by applying GA/PVP-SA 2 mM as an edible coating, fruit tissue breakdown can be minimized, and the shelf life of peach can be extended up to 10 days without symptoms of tissue breakdown.

Analysis of Alternative Shelf Life-Extending Protocols and Their Effect on the Preservation of Seafood Products.

Seafood is essential to a healthy and varied diet due to its highly nutritious characteristics. However, seafood products are highly perishable, which results in financial losses and quality concerns for consumers and the industry. Due to changes in consumer concerns, demand for healthy products has increased. New trends focusing on reducing synthetic preservatives require innovation and the application of additional or alternative strategies to extend the shelf life of this type of product. Currently, refrigeration and freezing storage are the most common methods for fish preservation. However, refrigeration alone cannot provide long shelf-life periods for fish, and freezing worsens sensorial characteristics and consumer interest. Therefore, the need to preserve seafood for long periods without exposing it to freezing temperatures exists. This review focuses on the application of other approaches to seafood products, such as biodegradable films and coating technology; superchilling; irradiation; high-pressure processing; hyperbaric storage; and biopreservation with lactic acid bacteria, bacteriocins, or bacteriophages. The efficiency of these techniques is discussed based on their impact on microbiological quality, sensorial degradation, and overall preservation of the product’s nutritional properties. Although these techniques are already known, their use in the industrial processing of seafood is not widespread. Thus, the novelty of this review is the aggregation of recent studies on shelf life extension approaches, which provide useful information for the selection of the most appropriate technology and procedures and industrial innovation. Despite the fact that all techniques inhibit or delay bacterial proliferation and product decay, an undesirable sensory impact may occur depending on the treatment conditions. Although no technique appears to replace refrigeration, the implementation of additional treatments in the seafood processing operation could reduce the need for freezing, extending the shelf life of fresh unfrozen products.

Effect of Some Edible Coating Materials On Quality and Storability of Cherry Tomato Fruits During Cold Storage and Shelf Life Periods

This research was conducted in the Post-Harvest Laboratory of the Horticulture Department, Faculty of Agriculture, Zagazig University, Egypt, during two seasons of 2019 and 2020 to study the effect of dipping cherry tomatoes fruits in solutions of edible materials on fruits quality and storability during storage at 7±2°C and 90 ± 3% relative humidity for 28 days. Where the fruits were dipped in chitosan nano particles (ChNPs) solution at 0.5 and 1 %, Arabic gum solution at 5 and 10%, bottle gourd seed oil at 0.2 and 0.4 % and distilled water (control). The results showed that, fresh weight losses, fruit decay, total soluble solids (TSS) content, fruit red color value a*and fruit red color value a*/b* increased progressive as the storage duration was extended from zero to 28 days. On the other hand, increasing the cold storage time reduced the fruit firmness, titratable acidity, vitamin C content and fruit red color value b*. Dipping in solution of bottle gourd seed oil at 0.4% gave the highest fruit firmness, vitamin C and the lowest values of weight loss percentage, Also, dipping in bottle gourd seed oil solution at 0.2 and 0.4 % did not show any decayed fruits and gave the highest values of a*/b*ratio, in addition, it is increased TSS in fruits at 28 days of storage. In general, ChNPs solution at 1 and Arabic gum solution at 10% % gave the highest values of titratable acidity.

Impact of Starch Coating Embedded with Silver Nanoparticles on Strawberry Storage Time.

The strawberry has a very short postharvest life due to its fast softening and decomposition. The goal of this research is to see how well a starch-silver nanoparticle (St-AgNPs) coating affects the physical, chemical, and microbiological qualities of strawberries during postharvest life. Additionally, the effect of washing with running water on silver concentration in coated strawberry fruit was studied by an inductively coupled plasma-optical emission spectrometer (ICP-OES). Furthermore, the shelf-life period was calculated in relation to the temperature of storage. Fourier transform infrared-attenuated total reflectance (FTIR-ATR), UV-Visible, and Transmission Electron Microscopic (TEM) were used to investigate the structure of starch-silver materials, the size and shape of AgNPs, respectively. The AgNPs were spherical, with an average size range of 12.7 nm. The coated samples had the lowest weight loss, decay, and microbial counts as compared to the uncoated sample. They had higher total acidity and anthocyanin contents as well. The washing process led to the almost complete removal of silver particles by rates ranging from 98.86 to 99.10%. Finally, the coating maintained strawberry qualities and lengthened their shelf-life from 2 to 6 days at room storage and from 8 to 16 days in cold storage.