Physiological and biochemical studies during fruit ripening in litchi (Litchi chinensis Sonn.)

Abstract

Postharvest treatment with Alar or cobaltous chloride was found to be the most effective in increasing the shelf life of litchi (Litchi chinensis Sonn.) fruits by up to 4 days. These treatments significantly reduced the physiological weight loss, titratable acidity and ascorbic acid content while an increase in total soluble solids and sugar content was recorded. Pectinmethylesterase (PME) activity was high in full ripe fruit and low in overripe fruit. The increase in PME activity was significantly less in fruits treated with Alar or cobaltous chloride. Furthermore, reduced levels of peroxidase, cellulase and respiratory activities were observed in treated fruits. The data suggest that slow rates of these biochemical attributes are helpful in extending the shelf life of litchi fruits.