Introduction. Our investigation aimed to examine the influence of eco-friendly edible coatings composed of sodium alginate, olive oil and green tea extract (GTE) on improving the shelf life and nutritional quality of carambola (A. carambola L.). Materials and methods. The combinations and concentrations of composite coatings tested were (2% sodium alginate + 0.1% olive oil) (T1), (2% sodium alginate + 0.2% olive oil) (T2) and (2% sodium alginate + 0.1% olive oil + 0.25% GTE) (T3), while the untreated fruit served as control (T4) and were stored at (25 ± 5) °C and (65 ± 5)% RH. All the stored fruit were subjected to physico-chemical and biochemical analysis at regular intervals of 4 days up to 16 days of their storage period. Results and discussion. Weight loss and decay occurrence were least in the fruit treated with T1 and T2 as compared with those of T3 and uncoated fruit (T4). The contents of total soluble solids, total sugars and changes in pigments were found to be least in fruit treated with T1 followed by those treated with T2 and T3. The addition of GTE (T3) to treated fruit during the storage helped enhance the antioxidants such as total phenols and ascorbic acid. Conclusion. The composite edible coatings tested in our study enhanced the shelf life of coated carambola fruit, i.e., thirteen days for T1, sixteen days for T2, fourteen days for T3 and twelve days for control or untreated fruit (T4); the nutritional quality of carambola was enhanced with the treatment of edible coating containing GTE.

Introduction. The peel of bananas that ripen at ≥ 24 ℃ does not turn fully yellow, but retains a green colour, reducing the commercial value of the fruit. Historically, in experimental studies of this problem, fruit are ripened at constant temperatures; for example, either 20 ℃ or 30 ℃. In our experiments, we systematically varied the temperature of banana storage during ripening to investigate early events in ripening that may determine whether or not the peel remained green. Materials and methods. Fruits were exposed to temperatures of 20 ℃ or 30 ℃ for short periods before then storing at 30 ℃ or 20 ℃ to complete ripening. The L* a* b* colour system was used to measure change in green colour in the banana peel. Results. If the temperature of the fruit stored was 20 ℃ for the first few hours (≥ 14 h), then the peel became fully yellow, even in fruit subsequently ripened at 30 ℃. Conversely, if the temperature of the bananas stored was 30 ℃ for the first few hours of ripening, then full yellow colour was not obtained even if fruits were subsequently ripened at 20 ℃. Conclusion. The temperature of the first few hours of banana ripening determines whether or not the peel reaches full yellow colour.