Optimization of Coconut Water Beverage Fermented with Lactobacillus acidophilus

Abstract

Coconut water is the liquid endosperm of coconut. It is a very nutritious and refreshingly natural beverage but highly perishable. The study aimed to optimize and evaluate the coconut water beverage formulation. A 33 factorial experiment arranged in Central Composite Design with the levels of Lactobacillus acidophilus starter culture (10, 15, 20%), pineapple puree as flavorant (5, 15, 25%) and sugar (10, 20, 30%) as the independent variables was used. The growth pattern of the lactic acid bacteria was monitored for 32 hours following serial dilution and pour plating techniques to determine the fermentation time to produce the beverage. Sensory evaluation was conducted using the 9-point Hedonic scale. Response surface methodology was used to identify the optimum formulation. Microbial growth indicated that 24 hours of incubation at 37°c can produce the fermented beverage. With increased level of Lactobacillus acidophilus starter culture, pineapple puree and sugar, acceptability for the product increased. The optimum formulation has 30% sugar, 20% starter culture and 15% pineapple puree. The product is more nutritious than the unfermented beverage and still acceptable when stored at refrigerated condition for 15 days. Fermentation increased the nutritional values of fresh coconut water.