Scientific Essay from the year 2014 in the subject Health - Nutritional Science, grade: 8.52, Gautam Buddha University (Gautam Buddha University (GBU), Greater Noida-201308, Uttar Pradesh, India), course: M.Tech, language: English, abstract: The aim of this study was to develop a probiotic beverage using whey and Watermelon juice Lactobacillus acidophilus was used as the probiotic organism. Optimization of the probiotic watermelon beverage as well as the establishment of a sensory profile by using chemical, microbiological, and quantitative descriptive analysis. For best blend optimization, we used RSM 6.0 trial software. Fermentation time using 1 per cent inoculum of L. acidophilus was optimized on the basis of RSM trial version, The 65:35 blend ratio of whey and watermelon juice fermented for 24 hrs. gave desirable results with highest sensory scores for overall acceptability and a total viable count of more than 106 cfu ml-1.beverage kept for 20 days below refrigerated temp and 120 hrs. at ambient temperature for the analysis for sensory and changes in titrable acidity, pH, total viable count.