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Papaya (Carica papaya L.) is available all-year round in Thailand, but the export volume is low. This may be attributed to unsuitable
temperature control during postharvest management resulting to unacceptable quality. This study aimed to investigate
the impact of intermittent warming (IW) on the quality of ‘Holland’ papaya during cold storage. Fruit with 25% peel yellowing
were exposed to four conditions: untreated fruit stored at 5C (T1; control), 15C (T2) and 2 IW conditions. These were T3
where fruit was stored at 5C for 4 days then moved to 15C for 1 day and T4 where the fruit was stored at 5C for 4 days then
moved to 15C for 1 day and the process repeated. For by T3 and T4 conditions the fruit were then stored at 5C, 90% RH until
the end of storage. The results showed that, after ten days, fruit stored at 15C, 80% RH had higher trend in L* and Chroma.
It was also found that their hue angle was significantly (p < 0.05) lower than when the fruit had undergone other treatments.
The fruit stored at 15C showed the highest level of respiration and the highest ethylene production rate while the control fruit
showed moderate levels. Under both IW conditions the respiration and ethylene production rates were suppressed up to day 9
and the rates increased after that. The control fruit failed to ripen but the IW fruit continued to yellow after 10 days. The control
fruit could only be kept for 5 days as they expressed chilling injury (CI) scale from 2 to 4 as moderate (50%), moderate to
severe (16.7%) and severe (16.7%) after 10 days of storage. The fruit stored under IW1 condition suered moderate to severe
CI (scale 2-4, 66.7% in total) after 20 days of storage. However the IW2 fruit exhibited only moderate and moderate to severe
CI (scale 2 & 3, 33.3% in total). This research concluded that storage using IW2 condition was best at retaining the quality of
stored papaya fruits for 20 days.