EFFECT OF THERMOSONICATION ON QUALITY OF SWEET ORANGE JUICE

Loading...
Thumbnail Image
Date
2023-05-19
Journal Title
Journal ISSN
Volume Title
Publisher
ACHARYA NG RANGA AGRICULTURAL UNIVERSITY
Abstract
Sweet orange or sweet lime (citrus sinensis (L.) Osbeck) is commonly known as “Mosambi” in Indian sub-continent. It is native to Asia and widely cultivated in India. Sweet orange is enjoyed, most either as a juice or whole fruit which is a rich source of vitamin-C and minerals like calcium, phosphorous, potassium and iron. About 95% of the fruit is essentially sold as fresh due to lack of processing technologies. Thermal processing along with chemical preservatives is widely used for preservation of fruit juices. Thermal processing of juices cause unwanted changes in taste and odour with damage to bio-active components and functional properties. Thermosonication is a good alternative technique to replace the conventional heat treatment process. It is a combined method of applying ultrasound at low temperatures which is an effective non-thermal processing method in inactivating microorganisms and enzymes at less processing time with minimum cost. The thermosonication of sweet orange juice was carried out at temperature (40,50 and 60°C), amplitude (40,70 and 100%) and sonication time (5, 12.5 and 20 min). Response surface methodology following Box- Behnken design was used to optimize the response parameters i.e., pH, TSS, ascorbic acid and titrable acidity. No significant changes were observed in pH and TSS during thermosonication treatments. Ascorbic acid and titrable acidity showed significant change in thermosonication treatments. The optimized conditions for thermosonicated sweet orange juice were observed as temperature of 40°C, 40% amplitude and sonication time of 9.298 min. During the storage period, pH, TSS and total sugars of thermosonicated sweet orange juice processed at optimized conditions, slightly increased from 3.8 to 4.1, 11.0 to 13°Brix and from 10.096 to 11.66% at refrigerated storage. The ascorbic acid and titrable acidity of the treated juice decreased from 49.13 to 38.59 mg/100mL and from 1.12 to 0.84% at refrigerant storage. No change in residual activity of PPO and POD of juice during refrigerated storage was observed. The maximum microbial count of 19 x 104 CFU/mL and the maximum fungal count of 13.5 x 103 CFU/mL were observed in thermosonicated juice sample on 28th day of storage at refrigerated conditions. The shelf life of the thermosonicated sweet orange juice was observed as 24 days at refrigerated storage. Keywords: Microbial inactivation, polyphenol oxidase, peroxidase, shelf life, sweet orange, thermosonication.
Description
EFFECT OF THERMOSONICATION ON QUALITY OF SWEET ORANGE JUICE
Keywords
Citation
Collections