COMBINED EFFECTS OFγ-IRRADIATION AND ASCORBIC ACID ON THE PHYSICOCHEMICAL PROPERTIES, MICROBIAL STABILITY AND AROMA PROFILE OF ONION PUREE DURING STORAGE

摘要

The onion was first pureed and then added with 0.5% ascorbic acid before it wasrnγ-irradiated at 2 kGy. The puree was then stored at 4, 10 and 27C for up to 28rndays. Changes monitored included pH, titratable acidity, total soluble solids, color,rntotal bacteria and yeast counts, organic acids and sensory property of the puree.rnResults show that the combined treatments reduced the contamination levels ofrnthe total bacteria and yeasts, and it helped to stabilize the color, and other physicochemical properties, such as pH, acidity, organic acid composition and contents ofrncold-stored onion puree. This study has shown that onion puree kept the initialrncolor of fresh onion puree after 2 kGyγ-irradiation if it contained 0.5% ascorbicrnacid and storage at 4C for 28 days.