EFFECT OF ULTRASOUND ON PRETREATMENT OF TUNA SKIN FOR GELATIN PRODUCTION

Abstract

This paper presents the result of study on the effect of ultrasound on extraction yield and quality of gelatin obtained from tuna skins using alkaline treatment method and alkaline-acid treatment method with ultrasound assistance. The results showed that ultrasound could shorten the time of alkaline treatment, while ensured the yield and the quality of obtained gelatin. Accordingly, the appropriate parameters of ultrasound mode that gave the best yield and quality of gelatin were determined as follows: for alkaline treatment method: amplitude of 80 %, period of 0.8s and ultrasound time of 90 min; for the alkaline-acid treatment method: amplitude of 8 0%, period of 0.8s and ultrasound time of 30 min. The former method produced gelatin with better yield and gel strength compared to the latter one (22.7 % and 143.3 g in comparison with 15.8 % và 122.4 g, respectively). The method with ultrasound support gave the gelatin with better quality in term of lipid content and gel strength in comparison with the traditional alkaline treatment method without ultrasound assistance.