Effect of enzymatic peeling process temperature on the sensory properties and chemical composition of Satsuma Mandarin fruit

Abstract

To encourage the consumption of Satsuma mandarin (Citrus unshiu Marc.), one of Japan's primary domestic fruits, we conducted a comparative investigation of enzymatic peeling of the segment membrane, with the aim of developing an easy-to-eat processed fruit product with fresh flavor and good taste. Sensory evaluation revealed that high-quality peeled citrus flesh with fresh flavor could be prepared by enzymatic peeling of the segment membrane using a polygalacturonase activity-based enzyme agent under low-temperature conditions (15°C). To investigate the effectiveness of enzymatic peeling compared to conventional chemical (acid and alkali) peeling, in terms of the composition of sugars, organic acids, and amino acids, we compared hand peeling (HP), chemical peeling with heating at 45°C (CP), enzymatic peeling with heating at 45°C (EH), and enzymatic peeling with cooling at 15°C (EC) using LC/MS/MS analysis. A significant increase in cis-aconitic acid and decrease in glutamic acid occurred with CP and EH, but not with HP and EC. Cluster analysis revealed that the flesh composition with EC was most similar to that of HP. It was concluded that EC fruit processing, which preserved the original fruit flavor and taste, represents an effective alternative to conventional chemical peeling.