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BACKGROUND: Food marketers desire residue‐free fresh grapes although grapes have a short postharvest life. This study was performed to determine the influences of pre‐ and/or postharvest chitosan (Ch) coatings on postharvest quality of minimally processed (stem‐detached) organic 'Crimson Seedless' berries. Berries were sorted as: (a) control (untreated berries); (b) preharvest Ch (dipping the clusters on the vine into 1% Ch 10 days before harvest at 20% soluble solid content (SSC)); (c) postharvest Ch (dipping the stem‐detached berries into 1% Ch); and (d) pre + postharvest Ch. Berries were stored in 12 × 15 cm rigid polypropylene cups for up to 42 days at 1.0 ± 0.5 °C. RESULTS: Pre‐ and/or postharvest Ch coating reduced weight loss during storage. Pre‐ + postharvest Ch was the best treatment for restricting polygalacturonase (PG) activity, extending the visual quality, color features (L*, C and h°), skin rupture force, biochemical (SSC, titratable acidity, maturity index and pH) and bioactive (total phenol content, antioxidant activity) features. Pre‐ or postharvest Ch was also significantly effective in maintaining many quality features. CONCLUSION: Pre‐ and/or postharvest 1% Ch coatings effectively maintained the quality of minimally processed grape berries of organically produced 'Crimson Seedless' grapes by delaying weight loss and PG activity and keeping the postharvest physical, biochemical and bioactive features for 42‐day cold storage at 1.0 ± 0.5 °C. The combined use of pre‐ and postharvest Ch found to be more effective than single treatment. Thus, pre‐ + postharvest 1% Ch coating could be recommended as an ecofriendly sustainable methodology for extending the postharvest quality of minimally processed fresh grapes. © 2024 The Author(s). Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Sustainable practices to extend the postharvest quality of horticultural products lead to cost-effective marketing during the prolonged season. Sweet cherries are among the most commonly consumed and traded fruits worldwide although they necessarily deteriorate after harvest. In the present study, the effects of UV-C irradiation in different application durations along with modified atmosphere packaging (MAP) on quality maintenance of the '0900 Ziraat' sweet cherries were investigated for two years (2018 and 2019). The fruits were divided into six application groups; (1) storage in plastic cups control, (2) using MAP (Xtend®) packages, (3) 5 min UV-C exposure, (4) 10 min UV-C, (5) 20 min UV-C, and (6) 30 min UV-C irradiation. Treatment of UV-C was performed at a 15 cm distance using a metal cabinet equipped with 8 UV-C lamps of 15 watts, 230V/50Hz at 254 nm wavelength. The sweet cherries were stored at 1 °C and 90% RH for 35 days. At the end of the storage, the greatest weight loss occurred in the control fruits, while the lowest loss was obtained from the fruits subjected to 10 min of UV-C for both years. Also, 10 min of UV-C provided the highest firmness value for both years. This treatment also has better effects on maintaining several quality features such as pedicel chlorophyll content, titratable acidity in fruit juice, and total phenolic contents compared to the control fruits. General findings indicated that 10 min UV-C irradiation would be a beneficial practice for extending the general quality features of '0900 Ziraat' sweet cherry during cold storage up to 35 d. [ABSTRACT FROM AUTHOR]

The present study was performed to determine effects of modified atmosphere packaging (MAP) on postharvest quality and chilling injury alleviation of tomatoes during low temperature storage. Tomatoes were harvested at two different stages (breaker and pink stage) and packed with MAP (Xtend® bags MAP). Air stored fruits were considered as control. All samples were stored at 5°C with 90% RH for 21 days. Weight loss, firmness, surface color, lycopene, ascorbic acid, total phenol, total antioxidant activity and chilling injury were investigated with intervals of 7 days. At the end of the storage, MAP of either breaker or pink fruits reduced the weight loss, maintained firmness and exhibited less biochemical changes than the control fruit. Moreover, tomatoes stored in MAP have less chilling injury than control at breaker maturity stage. The onset of chilling injury was also delayed by packaging compared to nonpack-aged fruits. The general qualities of MAP fruits were better than those of air stored fruits. Overall findings indicate that MAP can be an effective method for enhancing the phytochemical content, delaying the senescence and chilling injury of tomatoes at breaker or pink maturity stages during low temperature storage. [ABSTRACT FROM AUTHOR]

Demand for fresh grapes is increasing globally due to their rich composition in phenolic compounds, which have a strong antioxidant capacity. However, fresh table grapes deteriorate rapidly due to berry water loss and pathogen growth, which make it difficult to preserve without treatment. Chitosan coating, as a healthy, simple and innovative technology against to common SO2 fumigation, was tested at various concentrations (0%, 0.5%, 1.0% and 2.0%) for the effectiveness on postharvest quality extension of detached grapes of 'Alphonse Lavallée' cultivar. Chitosan coating at all doses significantly retarded the loss in berry weight, extended the skin rupture force and total phenol content. Visual quality was higher due to coating the berries with chitosan. Chitosan at all concentrations was effective on delaying maturity index (used to express postharvest senescence) and changes in berry colour values such as L*, C and Hue angle. Among the applied doses, 1% chitosan solution can be recommended to apply since higher doses were more effective with similar results on overall quality features of berries. Overall findings demonstrated that chitosan as an edible coating with their unique barrier can be utilized as a natural preservative of detached grapes to extend the postharvest quality up to 28 days. [ABSTRACT FROM AUTHOR]

Postharvest salicylic acid (SA) treatments can decrease the fungal decay of horticultural crops by affecting the ethylene biosynthesis and inducing the systemic resistance during cold storage. In the present study, effects of SA and modified atmosphere packages (MAP) on the postharvest quality maintenance of fruits of peach cv 'J. H. Hale' were investigated. After harvest at commercial maturity, half lot of each of the fruits was subjected to 1 mM SA for 5 min and was packed with or without MAP. The remaining lot was not subjected to SA but was also stored with or without MAP. All the fruits were stored at 1°C and 90% relative humidity for 60 d. Weight loss, color of flesh and skin, firmness, total soluble solid, titratable acidity, total phenolic and total antioxidant analyses were performed with 15 d intervals to compare the effectiveness of treatments. SA treatment had positive influences on the postharvest quality maintenance of the fruits. In particular, the combined use of SA and MAP was more effective than their individual use in maintaining the firmness of the fruits, delaying the biochemical changes in the flesh and alterations in the skin color. [ABSTRACT FROM AUTHOR]

A brief investigation of the effects of oxidation on the calorific values of three Turkish lignite samples has been made. The lignite samples have been vacuum dried and oxidized in pure oxygen at 35, 45, and 55 C at 100 kPa for 10 days. The calorific values of the oxidized and unoxidized samples have been measured. A relation has been observed between the extent of oxidation and decrease in calorific value. Various possibilities of modelling the relation have been explored. [ABSTRACT FROM AUTHOR]