EFFECTS OF DIFFERENT CULTIVARS AND FORMS OF SUGARCANE AS A MALT REPLACEMENT AND ADDITION OF PROBIOTICS LAB AND YEAST ON THE BEER QUALITY

Abstract

Brewing beer has four main ingredients: barley, hops, water, used to brew the malt, and yeast added during the fermentation process. However, at present, in industrial and craft beer, several other ingredients have been added to create a new flavor and at the same time reduce costs. Among plant varieties in Vietnam, sugarcane is considered a reasonable alternative material because of its high carbohydrate content and many minerals. In this study, there were three experiments including influence of sugarcane varieties (Comus (purple sugarcane), F.154 (green sugarcane), C.819- 67 (yellow sugarcane)), the influence in the ratio between malt and sugarcane (20%,40%,60%0 and differences in the types of sugarcane (cane plant and sugarcane juice) and the viability of probiotics (LAB and Saccharomyces boulardii) and their effects on beer quality were conducted. The results showed that beer brewed from green sugarcane with a ratio of 40% malt and sugarcane juice has the best results at 9 hedonic scale points. This beer sample had 7.25% alcohol by volume and the total phenolic content reachs176.68 mg Galic acid equivalent/L of beer and the antioxidant capacities reach 5.12 mg Ascorbic acid equivalent/L of beer. For the experiment of adding probiotics in the fermentation process, both yeast strains grew and survived after fermentation, Lactic acid bacteria reached 3*106 and Saccharomyces boulardii reached 4.33*106 by counting in the medium under suitable incubation conditions. From there, both types of beer from these two strains of microorganisms could be considered functional foods because they reach the minimum microbial count of 106 for foods considered to be functional foods.