Author : Prasit Ativeerakul

Summary : The chemical compositions of the pods and seeds of fresh bush sitao were determined immediately after harvest and after storage for 3, 6, 12, 24, 48, and 72 hours at 10 deg centigrade and ambient condition (30-32 deg centigrade). The pods contained higher amounts of chlorophyll, beta-carotene, total sugar, sucrose, glucose, and fructose than the seeds but lower ascorbic acid and starch. During storage, there was a progressive loss of chlorophyll, beta-carotene and ascorbic acid both in the pod and the seed. Higher temperature accelerated the loss. Starch was hydrolyzed in the pod at both temperatures with a faster rate at ambient. At 10 deg C, sucrose accumulated in the pod while it decreased at ambient storage. In the seed, sugar content decreased accompanied by an increase in starch at ambient conditions. Sensory evaluation of canned sitao stored for three months showed an adverse effect of postharvest storage on the canned product's quality. Texture, the most affected quality attribute, might be more affected by processing method rather than storage condition. Pre-processing storage at 10 degree C was recommended for not more than 48 hours and only for 12 hours at ambient condition.