PREPARATION & QUALITY EVALUATION OF WHEY BASED DRAGON FRUIT BEVERAGE AND STUDY ON ITS STORAGE STABILITY

Abstract

The main aim of this study was to prepare whey based dragon fruit beverage and study of its storage stability. Whey-based dragon fruit beverage was prepared by blending paneer whey along with dragon fruit juice and required amount of sugar utilizing design expert® (v 13) under mixed condition. By varying whey (50-100%) and dragon fruit juice (0-50%) seven formulations were obtained (A, B, C, D, E, F and G). Samples were pasteurized at 90°C for 10 min and stored in pre-sterilized bottles. The best sample F was selected and it’s chemical and phytochemical compositions were analyzed. It was stored in pre-sterilized bottles at ambient (25±5℃) and refrigerated (7±1℃) conditions for 25 days. The effect of storage time and temperature on physicochemical and microbial properties were evaluated. Formulated samples were analyzed by sensory evaluation and the beverage sample F with 62.5% whey and 37.5% dragon fruit juice was found to be superior. The best sample F was selected and it’s chemical and phytochemical compositions were analyzed. During storage analysis, TSS, acidity and reducing sugar increased while pH and ascorbic acid content decreased with progressing storage time in both storage condition. Similarly, during 25 days storage, total plate count & yeast and mold count were also increased under both storage condition. These changes in refrigerated storage condition were found to be minor in comparison to normal storage condition. From all the analysis, it can be observed that the beverage can be kept unspoiled for about 25 days without preservatives.