Postharvest quality of guapple (Psidium guajava L.) as influenced by hot water treatment and modified atmosphere packaging

Guapple (Psidium guajava L.) is one of the top 20 fruits in the Philippines with high nutritional value. The study was conducted to determine the effects of hot water treatment on postharvest quality of guava held in MAP at ambient or low temperatures and identify the most promising treatment that will maintain guava quality. Fruits were dipped at different hot water temperatures: (T1 – water, ambient (control), T2 – 44°C, T3 – 48°C, T4 – 52°C). Two harvested fruits were packed in 0.002 mm thick low density polyethylene (PE) bag or 0.05 mm thick polypropylene (PP) bag and in styrofoam plate with cling wrap and stored at ambient and refrigerated condition; unpacked fruit served as control. Ambient storage was done by keeping the fruits under ordinary room conditions while refrigerated storage was done using a chiller with temperature maintained at 7-10°C. MAP (styrofoam with thin plastic film, PE and PP) significantly delayed the shriveling and reduced weight loss of guapple fruit throughout the storage duration. Refrigerated guava fruits had significantly decreased fruit softening compared to fruits at ambient condition. There were no significant effects on softening of guava fruits in HWD-treated fruits under MAP treatments. MAP-stored guava fruits were significantly reduced softening than the fruits in open-stored fruits. HWD treatments had comparable results among all treatments. The rate of chilling injury was found significant between MAP and HWD under refrigerated storage. Chilling injury of open-stored guava fruits was significantly higher than the fruits in MAP stored fruits. Visual quality rating of MAP-stored guava fruits was significantly higher when stored at refrigerated condition than at ambient condition. Results further revealed that application of Hot Water Dip at 48°C of guapple fruits was effectively maintained the visual quality during storage. The results of this study provide valuable information on hot water dip, which can enhance the fruit quality of guapple fruit.