Fabricação de cerveja artesanal utilizando Saccharomyces cerevisiae var. boulardii como agente fermentador

Abstract

The beer market has become competitive in terms of product differentiation and added value. The search for products with health appeal, such as probiotics, has been growing exponentially. The yeast Saccharomyces cerevisiae var. boulardii isolated from lychee initially, has been used heavily as a probiotic in the treatment of gastrointestinal diseases. The objective of this work is the production of a Cream Ale style craft beer using Saccharomyces cerevisiae var. boulardii as a fermenting agent. The beverage production followed the basic steps of boiling, clarifying, cooling, fermenting, maturing and packaging. Yeasts were pre-inoculated using Dry Malt Extract. In formulation A the yeast S. cerevisiae US-05 was inoculated and in formulation B the yeast S. boulardii was inoculated in its commercial form, from Floratil®. Fermentation was carried out at a temperature of 17ºC for 2 days, the temperature was raised to 20ºC for another 10 days and the maturation took place at 0ºC for 10 days. After the beer was bottled, it remained at rest for another 20 days at an average room temperature of 15ºC. In the elaborated beers, the following physical-chemical analyzes were carried out: pH, color, bitterness, alcohol content, real extract, primitive extract and turbidity. The total phenolic compounds, total flavonoids and antioxidant activity were also determined by 3 different methods of the beers produced. Finally, a sensory analysis of the beers was performed by a descriptive method with the Flash Profile technique. Some values found for the physicochemical analyzes of formulation A were 4.59% ABV, 2.46 ºPlato for the real extract and 23.4 EBC for turbidity, where as in formulation B these values were 3.76% ABV , 4.11 ºPlato and 46.8 EBC, demonstrating that there was low substrate conversion and low attenuation. The beers presented parameters within the established by brewers reports for the Cream Ale style. For the bioactive compounds, the beer fermented with S. boulardii showed a higher amount of phenolic compounds and consequently antioxidant activity, except for antioxidant activity by the ABTS method, which showed no significant difference. The antioxidant activity of the produced beers has a strong correlation with the flavonoid content. In the sensory analysis, the terms that best described the beers produced were sweetness and yeast aroma, with no perceptible sensory differences between them.