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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]

The effects of gellan-based [gellan gum 0.56 % ( w/ v), glycerol 0.89 % ( w/ v) and sunflower oil 0.025 % ( w/ v)] edible coating on the respiration rate, physico-chemical properties and microbiological and sensory quality of fresh-cut pineapple during 16 days of storage (5 ± 1 °C, 85 ± 10 % RH) were evaluated. Uncoated fresh-cut pineapple was stored under the same condition and served as the control. For cross-linking reaction which was necessary for gel formation of gellan gum, a 2 % ( w/ v) calcium chloride solution that contained 1 % ( w/ v) ascorbic acid and 1 % ( w/ v) citric acid (as antibrowning agents) was used. The results obtained show that the respiration rate and weight loss of gellan-based coated samples were significantly ( p < 0.05) lower than those of the uncoated samples during 16 days of storage at 5 °C. In addition, coated samples significantly ( p < 0.05) maintained the firmness and colour of fresh-cut pineapple during low-temperature storage as compared to uncoated samples. The results obtained in this study also indicate that pH, titratable acidity and total soluble solids of coated and uncoated samples showed little changes during 16 days of storage at 5 °C. Gellan-based formulation did not show any antimicrobial effect, and no significant ( p > 0.05) differences were found among total plate counts and yeast and mould counts for coated and uncoated samples. Total plate counts and yeast and mould counts for coated and uncoated samples reached 10 CFU/g (limit of shelf life acceptance for fruit-based products recommended by the Institute of Food Science and Technology in the UK) after 12 days of storage at 5 °C. In addition, the scores for all sensory characteristics at day 12 were significantly ( p < 0.05) higher in coated samples as compared to control. Therefore, the results obtained in this study indicate that gellan-based edible coating formulation has the potential to maintain the quality of fresh-cut pineapple during low-temperature storage for about 12 days. [ABSTRACT FROM AUTHOR]