Development and quality analysis of watermelon juice blends with bitter gourd: ginger juice during storage

Abstract

Watermelon (Citrulluslanatus), Bitter Gourd (Memordica charantia) and ginger juice (Zingiber officinale) were formulated to a blend in different proportion (v/v) as T1 (90:05:05), T2 (80:10:10), T3 (80:15:05) and T0 (100:00:00) respectively. Sensory analysis and Physico‐chemical analysis were evaluated. Marginal changes in pH, Total Soluble Solids (TSS), acidity and vitamin C were observed .The results of the analysis of Vitamin C analysis content gave 74.91 mg/ 100 ml in standard watermelon juice, 58.11 mg/ 100 ml in T1, 53.72 mg/ 100 ml in T2, 40.62 mg/ 100 ml in T3 respectively. Titrable acidity of all blends increased (0.21-0.47) and pH of the juice decreased progressively during the storage period. This may be due to the fermentation process which generally took place during storage period and presence of lactic acid reducing micro‐organism in the juices. The mean overall acceptability scores up to 7 for T2 sample were observed. In microbial analysis, total plate count and total yeast and mould count, was analyzed up to 30 days with every 10 days interval counting and showed that microbial activity was very low on first day but it was gradually increased till 30 days of storage period to 27 x 102. These values were within the safe limit for juices, as they have not exceeded the standard values of 103cfu/ml. This indicated that the pasteurization (80oC for 3 min.) of the samples was efficient and the product was safe for consumption by consumer. However the shelf life of prepared beverage was established within 30 days.