Kinetics and effects of aeration and thermosonication on physiochemical, microbial and sensory properties of grape juice during storage periods
Pratheepa V, Kamalanathan G
The present work is aimed to study the kinetics and effects of combination of both aeration and thermosonication on physiochemical, microbial and sensory properties of grape juice during storage periods of 90 days. The main objective of the present work is to increase the shelf life of the grape juice but without adding any chemical preservative. The grape juice was aerated for 30 minutes and thermosonicated at 600C at various time intervals of 5,10,15,20 and 30 minutes to determine the pH, TSS, Titratable acidity, Ascorbic acid, Reducing sugar, Microbial load, and Sensory Properties during storage periods. It was observed that the optimum condition for aerated grape juice was 20 minutes thermosonicated sample and it had pH of 3.9, TSS of 17.5 ºBrix, Titratable acidity of 0.84 (g/100ml), Reducing sugar of 10.26 (µg/ml), Ascorbic acid of 2.65 (mg/100g) Microbial load of 3 (CFU/ml), and Sensory score of 9. The shelf life of grape juice was enhanced up to 45 days by combination of both aeration and thermosonication techniques.