Effects of maturity waxing and temperature on the postharvest behavior and storage life of durian

Three studies were conducted to evaluate the effects of maturity, waxing and temperature on the postharvest behavior and storage life of durian. Study 1 used three cultivars of durian ('Duyaya','Nanam' and 'Puyat') and four harvest periods or maturity stages(105, 110, 115 and 120 days after anthesis). Study 2 was carried out using 'Duyaya' treated with Fruit Gem as fruit wax. Study 3 was conducted with minimally processed cultivars of durian such as 'Duyaya', 'Nanam', and 'Puyat' and storage temperature of 5 deg C, -5 deg C and -10 deg C. Results of the study indicated that fruits harvested as early as 110 and 115 days from anthesis had qualities comparable with fuits at full maturity. A comparable Total Soluble Solids (TSS) of fruits was obtained at 110 to 120 days both at the ripe stage and at the limit of edibility. 'Puyat' and 'Nanam' when held in storage had also a comparable TSS of 31.66 and 30.22 deg Brix, respectively. Titratable Acidity (TA) of fruits at 110, 115 and 120 days was comparable which ranged from 0.27(120 days) to 0.31%(110 days). 'Nanam' was more acidic (0.68%) than 'Puyat'(0.63%) and 'Duyaya'(0.54%). Comparable Total Reducing Sugar (TRS) was obtained from fruits harvested at 110 days(7.41%), 115 days(10.15%) and 120 days(17.63%) upon ripening. Fruit weight loss at 110 days(8.65%) was already comparable with 115 days(7.63%) and 120 days(8.88%). Puyat had the highest weight loss of 10.54% followed by 'Duyaya' and 'Nanam' at 6.39% and 8.01%, respectively. When held in storage, 'Duyaya' was observed to have a shelf-life for six days, four days for 'Nanam' and 'Puyat' at three days. Acceptability through sensory evaluation indicated that upon ripening, fruits harvested at 105 days and 110 days were liked moderately while those at 115 and 120 days were liked very much. Waxing durian fruits resulted to lower weight loss of 11.36% and TA of 0.29%. Furthermore, this increased shelf-life by 8 days from ripening, waxed fruits were liked extremely and rated as moderately sweet. Waxing did not impart off-odor, it retained the full durian aroma and dark yellow interms of color intensity. At third month of storage, holding the minimally processed durian at -10 deg C had the highest TSS of 23.56 deg Brix. This has also extended the shelf-life by a period of three months.