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Summary: This work aimed to determine the total anthocyanin and phenolic contents and antioxidant capacity of extracts of the black rice's cold, hot and ultrasonic‐assisted extracts and their preservative effect on the storage quality of beef patties. The three extracts exhibited high anthocyanin, phenolic content and antioxidant capacity, and they were used in beef patties at five treatments (negative control without extract, positive control with 0.01% butylated hydroxytoluene (BHT), 7.5% cold extract, 7.5% hot extract and 7.5% ultrasound‐assisted extract). Raw and cooked beef patties were tested at 0, 3, 6, 9 and 12 days of cold storage in aerobically packaged polyethylene containers regarding pH, oxidative stability, antioxidant capacity and microbial quality. While adding black rice extracts did not influence the proximate composition of raw samples (P > 0.05), it slowed down the pH and lipid oxidation during storage and provided pH and thiobarbituric acid reactive substances (TBARS) stability in all final products. The BHT and treatments with extract indicated a higher 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) value than the negative control. Also, the incorporation of black rice extracts slightly retarded bacterial growth. These results suggest that the black rice extracts at 7.5% can be used effectively to protect beef patties from microbial spoilage and oxidation during cold storage for 12 days. [ABSTRACT FROM AUTHOR]

Summary: The objective of this study was to evaluate the effect of slurry ice (SI) in physicochemical changes, water migration, myofibrillar protein characterisation, and extended shelf life during cold storage of pufferfish (Takifugu obscurus). SI provided faster cooling rate, better structural stability of muscle tissue, and a significant reduction in total viable count (TVC). In addition, the use of SI treatment resulted in a considerable reduction in total volatile basic nitrogen (TVB‐N) and pH. The results of the texture profile analysis (TPA) demonstrated that SI had a significant inhibitory effect on the reduction of hardness, springiness, resilience, and chewiness. In addition, SI treatment better maintained a well‐structured myofibrillar protein stabilising the tertiary structure. Low‐field nuclear magnetic resonance (LF‐NMR) and magnetic resonance imaging (MRI) revealed that SI treatment could retard the water migration. Furthermore, the results of confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) indicated that SI treatment of pufferfish effectively slowed down the degradation of their myofibrillar protein fraction throughout the cold storage. [ABSTRACT FROM AUTHOR]

Summary: This work investigated the effect of bacterial cellulose nanocrystals (BCNCs)‐gelatin (GelA)/cinnamon essential oil (CEO) emulsion coatings (BCNCs‐GelA/CEO) on the shelf‐life extension of button mushrooms (Agaricus bisporus). CEO loadings between 1200 and 2400 μL/L were used in the coatings applied on the mushrooms' surface. The overall quality of coated mushrooms was monitored over 15 days of cold storage (4 ± 0.5 °C). Regardless of the storage time, using the highest amount of CEO within the coating formulation minimised the impact on tested parameters (weight loss, firmness, percentage of opened caps, total soluble solids, content of ascorbic acid and soluble protein, PPO/POD enzymatic activity) as compared to control samples. Interestingly, a linear relationship (R2 = 0.96 on average) between CEO concentration and the respiration rate of coated mushrooms was disclosed. Overall, this study pinpointed the capability of BCNCs‐GelA/CEO coatings to delay the aging process of button mushrooms under cold storage. Our findings could be applied to address the issue of food losses, highlighting the positive role of coating technology in enhancing the efficiency of the early stages of the food supply chain, especially in the case of button mushrooms. However, an assessment of the impact of the concentration of other coating components (BCNC and fish gelatin) on the shelf‐life extension of button mushrooms, as well as an evaluation of the coating's effectiveness in prolonging the shelf‐life of other food items, particularly non‐respiring products, is necessary to widespread the applicability of the proposed technology. [ABSTRACT FROM AUTHOR]

Summary: Postharvest application of 1‐methylcyclopropene (1‐MCP), lavender oil (LO) and geranium oil (GO) was investigated in alleviating chilling injury (CI) by regulating the cold tolerance of papaya cold stored at 4 °C for 16 days. The papaya was assessed on the attributes of CI, weight loss, firmness, colour, respiration rate, total soluble solids (TSS), soluble sugar (SS), proline and malondialdehyde content. The antagonistic effect of 1‐MCP against ethylene proved highly effective in delaying fruit ripening and metabolic processes. Notably, a 1‐h misting treatment with 600 mg L−1 1‐MCP (active ingredient, a.i.) solution significantly enhanced papaya's resistance to chilling conditions and reported a remarkable 2.08‐fold reduction in CI damage compared to the control. Furthermore, 1‐MCP‐treated papayas exhibited the highest proline concentration (61.59 μg/g FW) and the lowest malondialdehyde content (39.65 μmol/g FW). Additionally, 1‐MCP‐treated papayas displayed a 1.1‐fold reduction in oxygen consumption compared to the control. They also exhibited minimal changes in weight loss (3.6%), the least increase in TSS and SS compared to the control and better retention of fruit colour and firmness. Comparatively, GO known for its robust antioxidant and antimicrobial properties played a pivotal role in enhancing papaya's cold tolerance and providing superior protection against chilling‐induced damage when compared to the control. [ABSTRACT FROM AUTHOR]

Summary: The objective of this study was to apply multivariate data analytical methods to evaluate the effect of both storage conditions (cold and room temperature) and production systems (cage and free range) on the physical properties of chicken eggs produced under tropical conditions. The results of this study indicated that most of the physical quality parameters (Haugh units, egg weight, albumin height, yolk colour, shell breaking and shell thickness) measured in the egg samples stored at room temperature (RT) were lower compared with egg samples stored in cold room (CT) conditions. The weight loss rate (WLR) was higher in the egg samples from RT compared with CT conditions. Both egg samples from either CT storage conditions or FR production system had the best quality parameters (high Haugh units, heavy egg weights and low WLR). The highest classification rate using linear discriminant analysis was obtained for the prediction of systems of production where egg samples from cage (C) and FR were 83% and 80% correctly classified. However, the classification of weeks of storage provides with intermediate classification results based on the physical parameters measured where 75% and 72% of the samples were correctly classified as stored in CT or RT storage conditions, respectively. The utilisation of multivariate data analysis allowed for the analysis of all the variables at the time without the need to isolate effects such as birds age, housing systems or by the solely interpretation of a single parameter. [ABSTRACT FROM AUTHOR]

Summary: Carbon dioxide (CO2) has the potential to extend the storage time of raw milk, but its industrial application in this regard has not been thoroughly explored. This study aimed to investigate the microflora of CO2‐treated and untreated raw milk from South China using Illumina sequencing. The sequencing results confirmed the presence of Delftia, Pseudomonas and Serratia as the main spoilage species in raw cow milk from South China. However, CO2 treatment was found to selectively inhibit the growth of these spoilage bacteria. Principal coordinate analysis revealed differences in the microbiota structures of samples collected from the Fuyi and Guanyuan sites. Additionally, a total of 119 and 120 bacterial species were identified in the Fuyi and Guanyuan samples, respectively. The spoilage of raw milk from the Fuyi and Guanyuan was delayed by 7 and 19 days, respectively, with the application of CO2 treatment. Conversely, the samples without CO2 treatment were found to be contaminated with Pseudomonas fluorescens and Serratia. Moreover, the CO2‐treated samples from the Fuyi and Guanyuan ranches exhibited a different composition of spoilage bacteria, with a significant increase in the number of lactic acid bacteria (LAB) compared to the control samples. This study suggests that LAB have a remarkable tolerance to CO2, which is consistent with their selection in fruit, vegetable and meat products stored in CO2‐enriched modified atmosphere packaging. The findings of this study provide a foundation for further exploration of the potential application of CO2 treatment in raw milk processing. [ABSTRACT FROM AUTHOR]

Summary: This work evaluated the effect of a pectin‐based coating added with guava leaf extract on the quality and conservation of fresh beef during cold storage. Beef steak (CON), beef steak coated with pectin (PCB) and beef steak coated with pectin added with 5% guava leaf extract (PCB‐GLE) were evaluated for physical (weight loss, colour) and chemical (pH, lipid oxidation) parameters quality, as well as tissue modifications during 7 days of storage at 4 °C. PCB and PCB‐GLE showed the least weight loss, maintained the L* value and increased the a* value during the storage. Coated beef steaks showed lower lipid oxidation values during storage when compared with uncoated beef, highlighting samples covered with pectin coating added with guava leaf extract for the lowest TBARS indices during storage. Thus, the extract concentration added to the pectin coating showed potential antioxidant effect on beef steak. In fact, pectin‐based coating proved to be an excellent technology to improve the quality attributes of beef steak during refrigerated storage. [ABSTRACT FROM AUTHOR]

Summary: The quality changes of cold‐stored (4 °C) large yellow croaker (Pseudosciaena crocea) were studied by using stable chlorine dioxide combined with dual‐frequency ultrasound assisted‐slightly acidic electrolysed water (CUSS). The results of microbial indicators demonstrated that CUSS treatment inhibited microbial growth. Moreover, CUSS treatment had lower values of pH, total volatile basic nitrogen (TVB‐N) and thiobarbituric acid (TBA), and higher immobilised water content. CUSS treatment also inhibited the degradation of inosine monophosphate, suppressed the accumulation of hypoxanthine riboside and hypoxanthine. Through the results of texture profile analysis (TPA), protein degradation, and scanning electron microscopy (SEM), CUSS treatment could effectively protect the protein structure and maintain good texture characteristics of large yellow croaker. According to microbial indexes, K‐value, and sensory analysis, compared with dual‐frequency ultrasound treatment, CUSS treatment could prolong the shelf‐life of large yellow croaker for another six days. Therefore, CUSS treatment is a potential solution to preserve large yellow croaker, improving its protein characteristics. [ABSTRACT FROM AUTHOR]

Summary: Carambola is a nutrient‐rich tropical fruit that ripens and spoils rapidly at ambient temperature, making low‐temperature storage a preferable method to address this problem. Unfortunately, carambola suffered a chilling injury when stored at low temperatures. Carambola was vacuum impregnated with melatonin (MT), γ‐aminobutyric acid (GABA), and oxalic acid (OA) to mitigate chilling injury and improve its quality during cold storage. Carambola fruits were stored at 4 °C for 28 days and analysed every 7 days. Weight loss, firmness, physicochemical properties, phenolic content, flavonoid content, and proline content were assessed. MT‐treated carambola has the highest firmness, 146.31 g and lowest weight loss, 1.53% in comparison to others by the end of the storage period. Visual observations showed that MT‐treated carambola ripened evenly, without any chilling injury symptoms and decay was also delayed, whereas OA‐ and GABA‐treated carambola started to decay on day 28. Instead of degrading, phenolics and flavonoids were retained with 6.10% and 12.67% increase when compared to the initial level. GABA‐treated carambola can also retain its phenolic and flavonoid content; meanwhile, OA‐treated carambola can only retain its phenolic content. Therefore, MT can be applied to mitigate chilling injury and maintain the quality of carambola. [ABSTRACT FROM AUTHOR]

Summary: The impact of Aloe vera gel (AVG) coatings (0%, 25%, 50% and 75%) was evaluated on the ripening‐related quality parameters in 'Patharnakh' pear fruit during long‐term cold storage (0 ± 1 °C and 90–95% RH). Results showed that AVG coating extended the storage life of fruit by minimising mass loss, decay index, respiration rate, polyphenol oxidase activity, softening enzyme activities like pectin methylesterase (PME) polygalacturonase (PG) and cellulase and maintaining the preliminary sensory quality (SQ), firmness, soluble solid content (SSC), total phenols, titratable acidity (TA) over the control. Among all AVG treatments, 75% AVG treatment was found most promising for suppressing mass long, lowering respiration rate and preserved overall fruit quality up to 60 days of cold storage in 'Patharnakh' pear fruit. Hence, AVG proved as an alternative to non‐edible coatings for extending the pear's marketable span and cutting down the adverse effects of health and environmental hazards. [ABSTRACT FROM AUTHOR]

Summary: Spotted mackerel were stored at 5 °C for 0–5 days. To reveal changes in freshness and provide the fundamental knowledge of sarcoplasmic reticulum (SR), structural and biochemical changes were investigated by optical microscope, transmission electron microscopy and biochemical detection, including pH, myosin Ca2+‐ATPase activity, adenosine 5′‐triphosphate (ATP) content, SR recovery field and SR Ca2+‐ATPase (SERCA) activity. The result exhibited that SR swelled on day 1 and ruptured after 2 days. Muscle structure showed significant changes from day 0 to day 5. SERCA activity and SR recovery field were 0.46 μm Pi/min/mg and 1.05 mg/g at day 0 and 0.106 μm Pi/min/mg and 0.109 mg/g at day 2, respectively, highly corresponding to the decline of pH, myosin Ca2+‐ATPase activity and ATP content with a significant difference from day 0 to days 1 and 2. The biochemical properties of SERCA exhibited the maximum activity at pH 6.8–7.0 (0.408 μmol Pi/min/mg). Treated at pH 5.5 for 80 min or incubated at 35 °C for 40 min inactivated SERCA of 80%. Therefore, keeping at a freezing temperature of 5 °C and maintaining SR functionality was essential to delay freshness decrease. [ABSTRACT FROM AUTHOR]

Summary: The aim of this study was to explore the use of pulsed light (PL) for inactivating peroxidase (POD), polyphenoloxidase (PP0) and pectin methylesterase (PME) in melon juice. The influence of treatments on the optical, physicochemical and rheological properties of the juice was also evaluated. PL fluences between 3.6 and 71.6 J cm−2 caused a significant reduction in POD activity from 13% to 96% respectively. On contrary, PPO and PME activities were slightly or not significantly affected by the treatments. POD inactivation curve was successfully fitted with the first‐order and Weibull‐type models. Samples exposed to 35.8 and 71.6 J cm−2 showed minor changes in pH, titratable acidity and total soluble solids content than non‐treated juice along cold storage. PL treatments also better maintained the original colour of the fresh juice during storage. A slight but significant reduction in the apparent viscosity was observed due to PL exposure. Results indicated that pulsed light could be a useful technique for inhibiting POD activity and preserving the colour of melon juice along cold storage. Other preservation agent(s) in combination would need to be evaluated for better control of enzyme activity. [ABSTRACT FROM AUTHOR]

Summary: Magnetic field is an appropriate physical field, it can be used as a process parameter for the preservation of meat products. In this study, fresh beef was subjected to an alternating magnetic field of 2 mT during cold storage at 4°C, then microbial indicators, physicochemical properties of beef samples and its protein indicators were investigated. The results showed that the alternating magnetic field could inhibit the microbial growth on beef sample, and TVB‐N content, drip loss and characteristic putrefactive amine were lower than the control. The total bacterial count and TVB‐N value of beef samples in the control exceeded the threshold value on the 8th day, respectively, while the samples in the alternating magnetic field exceeded the threshold value on the 13th day. Meanwhile, it demonstrated that the field could delay the transformation of free amino acids to biogenic amines and inhibit the accumulation of bitter amino acids, so maintaining its nutritional characteristics. With the extension of storage period, the sulfhydryl content of beef myofibrillar proteins subjected to alternating magnetic field was lower than that of the control. It demonstrated that the protein oxidation of samples was inhibited, which would also be the reason the Ca2+‐ ATPase activity of myofibrillar proteins was maintained at a low level during the period. Furthermore, the upward trend of carbonyl group content was delayed. It provides a reference for the application of alternating magnetic field on cold storage of meat. [ABSTRACT FROM AUTHOR]

Summary: Mashua (Tropaeolum tuberosum), an Andean crop used in traditional medicine, has become of interest due to its phytochemicals specifically glucosinolates (GLS). Little is known about the impacts of cold storage and drying processing operations on the GLS composition of mashua‐derived products. This work evaluated the changes in GLS content and profile, derived from GLS biotransformation and myrosinase activity content, during controlled postharvest cold storage (12 °C and 80% RH) and after drying (60 °C and 1.8 m s−1). The GLS content reached its maximum value after 10 days of postharvest cold storage. The derivatives detected were 4‐Methoxybenzyl isothiocyanate, 4‐methoxy Benzeneacetonitrile, 4‐Methoxybenzyl alcohol methyl ether, Benzyl isothiocyanate and Benzeneacetaldehyde. The processing of tubers into flour resulted in significant GLS losses of 38%–87% compared with the respective cold storage treatment. Myrosinase activity showed no correlation with the content and type of GLS and low correlation with isothiocyanates and nitriles present. Our results revealed that drying conditions must be controlled to maintain GLS concentration in the final product. [ABSTRACT FROM AUTHOR]

Summary: This study evaluated the inhibitory effect of alternating magnetic field (MF) on enzymatic browning, physicochemical properties and microbial proliferation of fresh‐cut apples during cold storage. The results showed that after 9‐day storage, the browning index of apple slices increased by 174.07% in the conventional refrigerated group but by only 132.32% in the alternating MF group, the total number of colonies in the alternating MF group was 1.32 log CFU g−1, less than that in the conventional refrigerated samples. The soluble solids and firmness of the MF group were 16.47% and 28.79% higher than those of the control group. The alternating MF significantly inhibited the activities of polyphenol oxidase (PPO) and peroxidase (POD) and exerted a significant effect on the tertiary structure of enzymes. Except for maintaining the good sensory quality, the MF also suppressed the growth of microorganisms in fresh‐cut apples and extended their shelf life by at least 2 days. [ABSTRACT FROM AUTHOR]

Summary: In this study, the effect of alginate‐based coatings charged with quercetin glycoside compounds and hydroxyapatite/quercetin glycoside compounds (HA/QUE) on the microbiological quality, and on bioactive compounds of fresh‐cut papaya, was evaluated for 14 days at 6 °C. Alginate coatings with hydroxyapatite/quercetin showed a high capability to slow down the growth of all microbiological parameters investigated. At the end of cold storage, the total bacteria count in papaya samples covered with HA/QUE alginate coating was 4.8 log CFU g−1 which is significantly lower (P < 0.05) than 8.3 log CFU g−1 for uncoated samples. Total carotenoids' percentage decrease, at the end of storage, was about 20% in papaya with active coatings, with respect to the losses of 39 and 35%, registered in uncoated and alginate‐coated samples respectively. Vitamin C content and the antioxidant activity measured in papaya coated with HA/QUE alginate showed significantly higher values (P < 0.05) for each storage day than those detected for control‐ and alginate‐coated samples. Based on the sensory evaluation, active‐coated fresh‐cut papaya reached, at the end of the storage period, suitable values for commercial purposes. [ABSTRACT FROM AUTHOR]

Summary: Postharvest application of edible waxes blended with antioxidants is an effective strategy to regulate postharvest quality and antioxidant losses in fruits. Effect of beeswax coatings (BW 1.0% and 2.0%) alone or enriched with salicylic acid (SA) on antioxidant properties of pear fruit was studied during 67 days of cold storage and 20 days of supermarket storage conditions respectively. Results showed that under both the storage conditions fruits coated with BW + SA maintained higher total phenolic content (TPC), antioxidant activity and ascorbic acid content (AsA) as compared to the control. Furthermore, combined coatings significantly reduced polyphenol oxidase (PPO) activities and inhibited internal browning (IB) in pears throughout cold and supermarket storage. Overall, the BW 2.0% + SA 2.0 mM exhibited the most competitive effect in terms of preserving the antioxidant properties and preventing internal browning in pears during storage. [ABSTRACT FROM AUTHOR]

Summary: Cold‐stored banana fruit is particularly susceptible to chilling injury (CI). Over transportation and storage, CI is a key physiological factor affecting postharvest banana quality. Arachidonic acid (ARA) is considered a signal molecule that elicits stress signalling networks in plants. However, whether exogenous ARA treatment can reduce CI in postharvest fruit remains unknown. This study investigated the effects of a combination of exogenous ARA treatment and low temperature conditioning (LTC) on mitigating CI occurrence. ARA + LTC treatment decreased electrolyte leakage, accumulation of malondialdehyde, H2O2 content, weight loss and occurrence of CI symptoms. This treatment also delayed fruit softening and colour development, and maintained both vitamin C and chlorophyll contents in bananas stored at 0 °C for 36 days. In addition, ARA + LTC treatment significantly increased the activities of ascorbate peroxidase, glutathione reductase, peroxidase, catalase and superoxide dismutase. Concluding, ARA + LTC treatment has the potential to reduce CI in banana fruit during cold storage. This makes it an effective postharvest technique for fruits and vegetables susceptible to CI. [ABSTRACT FROM AUTHOR]

Summary: Korla fragrant pears were treated with CaCl2 and carboxymethyl chitosan coating (CC), while distilled water was used as control (CK) to clarify the effects of CaCl2 and CC treatments on the after‐ripening of Korla fragrant pears in cold storage. The results showed that the CaCl2 and CC treatments could maintain the balance of cell wall components and active oxygen metabolism, reduce membrane lipid peroxidation and damage, and delay and reduce the respiratory and physiological activity intensity, thus delaying the consumption of nutrients in the Korla pear during cold storage and preserving fruit storage quality. Compared with the CK group, both CaCl2 and CC treatments could effectively delay after‐ripening and reduce the intensity of physiological activity. Furthermore, the combination of CaCl2 and CC treatment groups yielded better results than the CaCl2 or CC treatments alone. [ABSTRACT FROM AUTHOR]

Summary: Effects of ultrasound combined with high hydrostatic pressure (HHP) on physicochemical properties,microorganisms and storage attributes of cold brew tea were investigated. HHP at 400 MPa/5 min/25 °C inactivated the total aerobic bacteria, yeast and mould in cold brewed tea prepared by static brewing (SB‐tea) at 13 h/4 °C, ultrasonic bath (UB‐tea) at 150 W/120 min/0 °C and ultrasonic pulveriser (UP‐tea) at 600 W/40 min/0 °C, ensuring their microbiological safety. The results showed that there was no significant difference in the concentration of tea polyphenols between hot brewed tea prepared by 7 min/100 °C and cold brewed tea under different preparation conditions, while the caffeine in cold brewed tea was significantly lower (P < 0.05) than that in hot brewed tea. During the storage period of 8 days, compared with the untreated group, the cold brewed tea after HHP treatment had better microbiological safety. In addition, HHP treatment constantly maintained the tea polyphenols, pH, colour, antioxidant capacity and turbidity in cold brewed tea. The untreated and HHP‐treated cold brew tea were evaluated by 20 trained volunteers. Results showed that UB‐tea was more close to SB‐tea than UP‐tea in sensory profile, while HHP seem to maintain a good sensory profile as well. Therefore, this particular combined technology of ultrasonic bath and HHP displayed considerable potential for application in the cold brew tea manufacturing industry. [ABSTRACT FROM AUTHOR]

Summary: Photodynamic treatment (PDT) is a novel cold‐sterilisation technology, but the evaluation of the protein quality of shellfish was scarce. In this study, the effects of curcumin (CUR)‐mediated PDT on delaying protein degradation of oysters during cold storage at 4 ℃ and the mechanisms were investigated. The protein‐degradation indexes and related enzymes were determined every 2 days. The results showed that the content of total volatile basic nitrogen (TVB‐N), polypeptide nitrogen (PeN), amino acid nitrogen (AN) and free amino acid (FAA) in photodynamic group was significantly different from the control group since the first 2 days (P < 0.05). The pH value was significantly changed by PDT at the 4th and 8th day (P < 0.05). Interestingly, the activities of serine and aspartic protease were significantly inhibited by PDT during the whole cold storage (P < 0.05). Therefore, the study indicated that PDT has a positive effect on preventing protein degradation. [ABSTRACT FROM AUTHOR]

Summary: The potential applicability of β‐carotene‐loaded nanoemulsion (CNE) as a natural colorant in non‐smoked sausage made from goat meat surimi‐like material (GMS) was elucidated. The effect of CNE content (0–30 g 100 g−1) on the physicochemical characteristic, oxidative stability and β‐carotene remaining during cold storage (4 °C) was determined. The higher the CNE, the greater the a*, b* and redness index with the lower L*, and colour likeness score. CNE content had a little impact on the moisture content, aw and pH of sausages over storage period. However, the expressible drip, breaking force and deformation were largely influenced by the CNE content. All CNE‐containing sausages displayed a superior oxidative stability to control. Among CNE‐incorporated samples, the lowest lipid oxidation and β‐carotene degradation were noticeable in the sausage with 10 g 100 g−1 CNE. Thus, the CNE at 10 g 100 g−1 was a promising functional colorant for emulsion sausage made from GMS. [ABSTRACT FROM AUTHOR]

Summary: Packages of ready‐to‐eat (RTE) wild rocket and lettuce baby leaves were subjected during 8 days of cold storage to a chronic temperature abuse (CTA) at sub‐optimal storage temperature (10 °C) or to a short‐term (6 h) abuse at ambient temperature (STA) to evaluate the impact of two temperature abuse scenarios on gas composition within the packages, leaf sensory quality and volatile organic compounds (VOCs). In both species, the CTA scenario had a markedly higher impact on gas composition, sensory quality and off‐odour formation than the STA, and the limit of sensory acceptability was reached in the CTA scenario 4 days or more earlier than in the STA. Sulphur compounds were the main responsible for off‐odour perception in both leafy salads. Results from the present study may be useful in the assessment of critical points in the cold chain of RTE fresh produce and in prioritising actions towards improved cold‐chain management. [ABSTRACT FROM AUTHOR]

Summary: Cryopreserved fruits usually develop symptoms, which affects the release of aroma. Our study investigated the impact of exogenous methyl jasmonate (MeJA) upon the synthesis of aromatic esters in 'Nanguo' pears after cold storage. It found that exogenous MeJA enhanced ethylene accumulation via improving the activity of 1‐aminocyclopropane‐1‐carboxylic‐acid (ACC) synthase (ACS) and ACC oxidase (ACO) and the expression levels of PuACS1 and PuACO1. After cryopreservation for 90 days, the ester aroma of 'Nanguo' pears was effectively improved by MeJA during normal temperature shelf life. In addition, the expression of PuERS1, PuETR1, PuEIN4, PuEIN2 and PuERF1 in MeJA‐treated fruits were obviously increased. Therefore, we infer that the influence of MeJA on production of aroma‐related esters in 'Nanguo' pears is closely connected with ethylene biosynthesis and signal transduction, namely increase activity of ACS and ACO, and upregulation of the expression level of PuACS1, PuACO1, PuERS1, PuETR1, PuEIN2, PuEIN4 and PuERF1. [ABSTRACT FROM AUTHOR]

Summary: In this study, the inhibitory effects of natural trypsin inhibitor from soybean (SBTI) on texture deterioration of adductor muscle of scallop (AMS) during cold storage and its mechanism were revealed by determining the changes of structural proteins of AMS in situ and in vitro, respectively. Results indicated that the endogenous proteolysis resulted in the disintegration of connective tissue proteins, the degradation of myosin and actin, as well as the reduction of α‐helix, the increase of β‐sheet and amino acid side chains, and the exposure of tryptophan residues of isolated myofibrillar proteins (MPs). These changes in structural proteins contribute to the texture deterioration of AMS as reflected in a significant decrease in hardness, chewiness, adhesiveness and springiness, but a significant increase in cohesiveness. SBTI significantly inhibited the conformational changes of structural proteins caused by endogenous proteolysis, improved the MP gel‐forming ability and consequently retarded the texture deterioration of AMS. [ABSTRACT FROM AUTHOR]

Summary: The influence of regular air cold storage (7 °C and 85 ± 5% RH) followed by ripening at shelf‐life conditions (19–21 °C and 65 ± 5% RH), on bioactive compounds of Hass avocados was investigated. Results showed that the content of mannoheptulose and perseitol decreased significantly already during cold storage and ripening period. The fatty acid profile and contents of tocopherols (α‐ and β‐tocopherol) and phytosterols (β‐sitosterol, stigmasterol, campesterol) remained unchanged from day 0 to edible ripeness. Total phenolics, hydrophilic and lipophilic antioxidant capacity remained unchanged during cold storage and increased during the ripening period. At edible ripeness, significant amounts of phenolic acids, p‐coumaric and caffeic and their derivatives were synthesised. Our results demonstrated that regular air cold storage for up to 37 days followed by ripening at shelf‐life conditions enhances the phenolic compounds and mainly the hydrophilic antioxidant capacity without affecting the remaining bioactive compounds in Hass avocado. [ABSTRACT FROM AUTHOR]

Summary: Aquafaba, the viscous liquid recovered from canned chickpeas, was used as egg replacer for the development of vegan mayonnaise. The textural, microstructural and physicochemical properties of mayonnaise were determined during cold storage to optimise the aquafaba‐to‐oil ratio (A/O) of the formulation (15%–25%/80%–70%). Aquafaba was capable to form a stable emulsion with an average value of droplet size distribution below 4 μm. The physical stability determined by the Turbiscan Stability Index (TSI) was unaffected by the A/O ratio during 21 days of storage at 4 °C. The lowest droplet size distribution was obtained for samples with a low A/O ratio (15/80%). Firmness, adhesive force and adhesiveness decreased (P < 0.05) with increasing the A/O ratio, whereas consistency remained unaffected. The oxidative stability of the oil phase was similar for all formulations and remained unaffected during storage. Aquafaba can be used effectively to replace egg in mayonnaise formulations containing oil at standard levels. [ABSTRACT FROM AUTHOR]

Summary: This study develops a predictive model for determining freshness of salmon fillets during cold storage at different temperatures using electronic nose combined with principal component analysis (PCA) and radial basis function neural networks (RBFNNs). The electronic nose sensed ammonia/amines, hydrocarbons, solvents and aromatics that increased during storage. The concentrations of the volatiles were compared with the increased thiobarbituric acid (TBA), total volatile basic nitrogen (TVB‐N), total aerobic bacteria count (TAC) and decreased of sensory assessments (SA). Gas chromatograph–ion mobility spectrometry analysis confirmed the changes in gas species. RBFNNs and PCA were used to establish predictive models and the relative errors of TBA, TVB‐N and TAC by the PCA‐RBFNNs model were all within ±10% and SA was within ±15%. These results suggest that the PCA‐RBFNNs model can be used to predict changes in the freshness of salmon fillets stored at −2 to 10 °C. [ABSTRACT FROM AUTHOR]

Summary: Four different levels (25–100%) of culled goat meat were used in frankfurter formulation (frankfurters G25, G50, G75 and G100) instead of beef (CON). Technological properties, fatty acid profile and sensory properties were examined during the 6‐week cold storage. The formulation had significant impact of fatty acids profile – n‐6/n‐3 ratios progressively decrease from 14.63 in CON to 6.63 in G100. Higher goat meat content led to progressively higher lightness and lower redness in frankfurters. This was also observed by consumers but not negatively perceived. Check‐all‐that‐apply (CATA) analysis shows that more than 80% of consumers marked pleasant colour as present in goat frankfurters and CON. The similar was observed for pleasant appearance, pleasant odour, tasty, soft and juicy. Moreover, atypical taste and odour were mostly not marked as present (73.8% and 62.5%, respectively). The panellists pointed at G50 as the most preferred, while consumers most frequently marked G75. [ABSTRACT FROM AUTHOR]

Summary: Selected physico‐chemical and proteolysis‐related parameters were evaluated in dry‐cured loins inoculated with probiotic (Lactobacillus rhamnosus LOCK900, Bifidobacterium animalis subsp. lactis BB12) and potentially probiotic (Lactobacillus acidophilus Bauer Ł0938) lactic acid bacteria (LAB) strains and compared with a control sample at five different storage times (28, 90, 180, 270 and 360 days). Physico‐chemical parameters of dry‐cured loins were significantly (P < 0.01) affected by treatment, storage time and the interaction between them. The count of lactic acid bacteria (LAB) in dry‐cured loins was in accordance with their pH. Higher intensity of proteolysis, as assessed by non‐protein nitrogen content (NPN) and proteolysis index (PI), occurred in inoculated samples. Based on the SDS‐PAGE analysis, the modifications produced during storage on the sarcoplasmic proteins were more pronounced than those exerted on the myofibrillar protein fraction. However, inoculation effect was absent from SDS‐PAGE protein patterns. [ABSTRACT FROM AUTHOR]

Summary: The γ‐aminobutyric acid (GABA) contained in mulberry leaves has the effect of improving mood. Mulberry leaf cultivars 'Kangxuan 01‐28', 'Lunbai No.1' and 'BR 60' were analysed for GABA accumulation under low temperature storage. The effects of ice temperature storage (ITS), cold acclimation combined with ice‐temperature storage (CACIS) and cold storage (CS) on GABA and associated enzymes, soluble protein and leaf colour were measured. The increase in GABA content differed among varieties. Under different low temperature storage treatments, the GABA concentration increased by 33.93‐fold, 11.75‐fold and 4.28‐fold in mulberry leaves compared with the initial concentration in the three cultivars 'Kangxuan 01‐28', 'Lunbai No.1' and 'BR 60', respectively. GAD activity and soluble protein were positively correlated with GABA concentration, while GABA‐T activity showed an opposite trend to the GABA concentration. After being treated with ITS, 'Kangxuan 01‐28' could accumulate higher GABA and should be consumed within 7 days. Under low temperature storage treatments, the GABA content of mulberry leaves increased. [ABSTRACT FROM AUTHOR]

Summary: The objective of this study was to increase quality and limited shelf‐life of boza (3–15 days), a traditional Balkan origin fermented beverage using lysozyme (LYS) and/or nisin (NIS). For this purpose, the effectiveness of NIS, LYS and LYS:NIS combinations was first tested in a broth medium at 4 °C for 3 weeks on Lactobacillus plantarum, one of the frequently isolated lactic acid bacteria in boza. Stability of LYS and NIS in boza, their effects on LAB counts, and chemical and sensory properties of boza were then evaluated during cold storage at 4 °C. Results of LAB counts as well as pH, d‐ and l‐lactic acid, and titratable acidity measurements showed that LAB in boza containing NIS (250 μg g−1) or LYS:NIS (500:250 μg g−1) could be controlled without reducing LAB counts below 6 log CFU mL−1 during 2 weeks shelf‐life. In contrast, LYS (500 μg g−1) alone could not control LAB in boza to delay its acidic spoilage. Positive effects of NIS and LYS:NIS application on quality of boza were also proved with sensory analysis by panelists and e‐nose measurements. This work showed that use of natural GRAS agents in preservation of fermented beverages containing probiotic LAB is possible without affecting their characteristic aroma and flavour. [ABSTRACT FROM AUTHOR]

Summary: We recently developed a postharvest low‐temperature‐conditioning (LTC) treatment for ‘Wonderful’ pomegranate fruits that involve prestorage exposure to 15 °C for 10 days, and it markedly enhanced chilling tolerance. To elucidate the molecular mechanisms involved in the fruit responses to LTC, we conducted RNA‐Seq analysis of ‘Wonderful’ pomegranate inner membrane tissue at four different time points: (i) immediately after harvest; (ii) after the LTC treatment; (iii) after 2 weeks of cold storage at 1 °C; and (iv) after LTC + 2 weeks at 1 °C. Pairwise comparisons revealed that 7798 transcripts were significantly (P ≤ 0.05) induced or repressed by a factor of at least four in the chilling treatment (2422 upregulated and 5376 downregulated) as compared with just 1997 transcripts in the LTC + chilling treatment (974 upregulated and 1023 downregulated). Thus, application of LTC mitigated the overall changes in transcript levels associated with cold storage. Furthermore, the LTC + chilling affected gene expression patterns related to regulatory and stress mechanisms, including modification of specific transcription factor, signalling and stress‐related genes. [ABSTRACT FROM AUTHOR]

Summary: The aim of this work was to study the behaviour of E. coli in mascarpone cheese during storage at the temperatures ranging from 3 to 15 °C, as well as application of predictive microbiology to describe the experimental data. The Baranyi, Gompertz and logistic models were fitted at the stage of primary modelling. Although all applied primary models described the growth of micro‐organisms accurately, the most accurate goodness of fit was obtained for the Gompertz model and the growth rates generated by this model were used for secondary modelling. The polynomial model predicted accurately the influence of temperature on the growth rate of E. coli, reaching the adjusted coefficient of linear regression 0.99. Generated predictive model that describes the growth of E. coli in mascarpone cheese constitutes a valuable tool in assessing the microbiological stability of the food product with similar physicochemical properties. [ABSTRACT FROM AUTHOR]

Summary: The oxidative damage to proteins during processing of ready‐to‐eat chicken patties and its impact on the nutritional value and texture properties of the product were assessed. The effect of cooking techniques (boiling, roasting and grilling) and microwave reheating (600 mW per 1 min) after 7 and 14 days of cold storage (+4 °C) were studied. Cooking methods had an effect (P < 0.05) on most protein oxidation parameters, including protein depletion of tryptophan, thiols, protein carbonylation and formation of cross‐links. Overall, the succeeding chilled storage led to an aggravation of the oxidative damage which occurred along with hardness increase and impaired digestibility. Microwave reheating had contradictory effects on protein oxidation parameters. An increase in protein carbonylation occurred along with a cleavage of disulphide bonds that would explain a decrease in hardness. This study illustrates to which extent the oxidative damage to meat proteins affects protein quality and nutritional value of a severely processed meat product. The impact of assorted cooked procedures on these events is also discussed. [ABSTRACT FROM AUTHOR]

The quality loss in fish during freeze-thaw cycles is considered one of the major issues caused mainly by temperature fluctuations during cold storage. The present work is aimed to illustrate the effects of brown algal phlorotannins ( BAP) and ascorbic acid ( AA) on physiochemical properties of minced snapper muscle through different freeze-thaw cycles. Both AA and BAP could retard lipid and protein oxidation, respectively, and synergistically. The Ca2+- ATPase activity can be protected with the addition of antioxidants. The addition of 0.1% (w/w) AP showed 22.6% higher activity as compared with other groups especially during three freeze-thaw cycles. Cooking loss was efficiently inhibited and 0.1% AA + 0.3% BAP group showed 25.5% lower than control. Antioxidant is also helpful to maintain gel-forming ability of minced snapper and 0.1% AA + 0.1% BAP group showed the best. These results revealed that both AA and BAP could prevent minced fish by inhibiting the protein denaturation during freeze-thaw cycles. [ABSTRACT FROM AUTHOR]

Predictive microbiology models are valuable tools for helping to assess and manage the risk of illness from food contaminated with human pathogens, such as Salmonella. However, multiple versions of a model may be needed for different food safety applications, such as hazard analysis and critical control point ( HACCP) programs and risk assessment. A neural network model for growth of Salmonella in ground chicken as a function of time (0 to 8 days) at 16 °C and serotype ( n = 8) was developed. The proportion of residuals in an acceptable prediction zone ( pAPZ) from −1 log (fail-safe) to 0.5 log (fail-dangerous) was 0.948 for training data ( n = 192) and 0.988 for testing data ( n = 84). A pAPZ ≥0.7 indicated that the model provided predictions with acceptable bias and accuracy. Thus, the model was successfully validated. Different versions of the model were developed for application in HACCP and risk assessment. [ABSTRACT FROM AUTHOR]

The potential of various concentrations of 24-epibrassinolide ( EBR) treatments on the control of grey mould in artificial Botrytis cinerea inoculation test and on the maintenance of postharvest quality of table grapes without inoculation in cold storage were researched. In the cold storage, clusters of grapes with exogenous EBR application ( EBR1, 0.1 mg L−1 EBR; EBR2, 0.4 mg L−1 EBR; EBR3, 0.8 mg L−1 EBR) were stored at 0 ± 1 °C. Fruits' quality attributes including berry firmness, weight loss, berry drop, decay berry percentages, total sugar and titratable acidity were measured at 15, 30 and 60 days. The results showed that EBR treatments exhibited a higher berry firmness and a lower percentage of weight loss, berry drop and decay berry. In the artificial inoculation trial, single berries were immersed in EBR1, EBR2 and EBR3, then inoculated by spraying with a B. cinerea spore suspension and stored at 25 ± 2 °C and 95% relative humidity. Disease severity ( DS), lipid peroxidation and defence-related enzymes of these berries were analysed every 2 days. EBR-treated berries resulted in an increase in activities of defence-related enzymes including superoxide dismutase, peroxidase, catalase and phenylalanine ammonia-lyase compared with control berries inoculated by B. cinerea. Simultaneously, significant decreases in DS and production of superoxide anion radical and malondialdehyde were observed. These results suggested that exogenous application of EBR could play a protective role in controlling the grey mould of postharvest grapes and maintaining the postharvest quality during cold storage. [ABSTRACT FROM AUTHOR]

The objective of this work was to study the impact of collagen on softening of grass carp ( Ctenopharyngodon idella) fillets during chilled storage. The fillets were stored under superchilling (−1.5 ± 0.2 °C) and with ice (0.2 ± 0.1 °C) for 21 days, and texture properties, collagen and the related enzyme activities were measured. Results showed that firmness and collagen content were strongly influenced by storage temperature and time. Fillet firmness decreased by 32.3% (superchilling) and 49.6% (ice stored) of the initial values after 3 days of storage, respectively. Total collagen content decreased with time, but different collagen fractions showed variations. Collagen degraded to different extents depending on storage conditions as indicated by SDS- PAGE and amino acid analysis. In addition, collagenase activity declined significantly during the first 3 days, followed by a slow increase. This study demonstrated that collagen degradation was involved in grass carp fillet softening and provided useful information for fillet quality improvement. [ABSTRACT FROM AUTHOR]

Effects of chilling (5 °C) prior to low intensity pulsed electric fields ( PEF) (0.1-1.1 kV cm−1) on vitamin C and activity of peroxidase ( POD) and ascorbic acid oxidase ( AAO) in carrot purée were studied. The effect of PEF on carotenoids extractability was evaluated and compared to that of purée pre-conditioned at 20 °C (control). PEF enhanced carotenoids extractability for purée with and without pre-chilling, up to 25% and 66%, respectively. Vitamin C content decreased after PEF but combined pre-chilling and PEF maintained vitamin C stability and reduced AAO and POD activities. AAO and the heat-stable POD fraction were found to be more thermolabile (i.e. higher kref value) after PEF, particularly at 0.6 kV cm−1, which implies elimination of their enzymatic action towards oxidation of bioactive compounds. It was suggested that chilling prior to low intensity PEF modified enzyme properties and secured the stability of vitamin C and carotenoids. [ABSTRACT FROM AUTHOR]

Vegetable soya bean deteriorates quickly after harvest at ambient temperature due to loss of green colour and consequent yellowing of grains. To seek an effective method to control the postharvest quality, the effect of exogenous spermine on visual quality, sugar loss and sucrose-metabolising enzyme activities of vegetable soya bean (Glycine max L.) during cold storage was investigated. The results showed that exogenous spermine (1.0 mmol L-1) noticeably prolonged shelf life, inhibited the increase of weight loss and decay index and retained the colour. It also significantly minimised sucrose loss by regulating the activities of sucrose-metabolising enzymes. Sucrose content negatively correlated with acid invertase (AI) activity at P < 0.05, while positively with sucrose phosphate synthase (SPS) activity at P < 0.01. There was no significant correlation with the activities of neutral invertase and sucrose synthase. These results indicated that the AI and SPS activities might play an important role in the control of sucrose metabolism resulting in reduction of sucrose loss. [ABSTRACT FROM AUTHOR]