Maintaining the quality of sugarcane juice with blanching and ascorbic acid

The physicochemical changes in fresh sugarcane juice stored at 10 degrees C were studied by determining juice yield, color, reducing sugar, titratable acidity, viscosity, pH, polyphenol oxidase (PPO), sucrose neutral invertase (SNI) and total microbial count. Results showed that blanching of stems before squeezing effectively prevented degreening and/or browning, and reduced activities of PPO and SNI in fresh sugarcane juice. Added ascorbic acid delayed the increase of reducing sugar, titratable acidity, viscosity and total microbial count, and also prevented degreening and/or browning with reduced PPO and SNI activities in fresh sugarcane juice during storage. Addition of 0.1% ascorbic acid seemed to be more effective than blanching of sugarcane stems, and was able to maintain the quality of fresh sugarcane juice for up to 5 days at 10 degrees C. Deterioration of fresh sugarcane juice was demonstrated as a rapid increase of titratable acidity and viscosity with a obvious browning. (C) 2007 Elsevier Ltd. All rights reserved.