Optimization and characterization of a value-added fermented ready-to-servewhey-based beverage with high antioxidant potential

Abstract

This study was conducted to optimize the process parameters for developing a Ready-To-Serve fermented whey beverage using pineapple juice and mint and characterize the drink. The levels of pineapple juice (20-40%), sugar (5-10%), and mint powder (1-3%) on pH, DPPH, TSS, and overall acceptability were investigated using a central composite design. The optimized process conditions achieved were 39.42% (v/v) of pineapple juice,5.75% (w/v) of sugar, and 1.01% (w/v) of Mentha. The beverage had 89.41% mg GAE/ml total phenolic content and 83.88% DPPH radical scavenging activity. FTIR spectrum confirmed the presence of the O-H stretch of phenolic compounds between3200 cm-1– 3518 cm-1 and conformational changes in the secondary structure of the whey protein at 1625-1647 cm-1 in the fermented sample. The beverage possessed all essential amino acids, the highest being Leu, Val, and Lys and PUFA (ω6/ω3=1.52)and MUFA levels of 6.7±0.96 and 21.57±0.02 mg/100mL,respectively. In addition, hypercholesterolemic fatty acids (C12:0,C14:0, C16:0) were significantly reduced after fermentation. Therefore, a serving of 100mL would contribute 3.53%, 2.96%,and 2.41% towards the RDA of Fe, K, and Mg, for an adult man,respectively. The whey beverage had acceptable microbiological quality on the 30th day of storage under refrigerated conditions. Fermentation with Pediococcus pentosaceus NCDC 273 reduced the coliform count by 5.57% and 4.04% and the Y&M count by2.2% and 2.9% on the 15th and 30th day of storage, respectively