Cerveja artesanal de trigo com adição do fruto do mandacaru (Cereus jamacaru DC.): bioatividade e perfil aromático

Abstract

With the craft beer market growing exponentially, driven by the diversity of ingredients incorporated into the manufacturing process, the demand for a diversified product with beneficial health properties has become a challenge for microbreweries and researchers. Faced with the infinity of non-conventional ingredients, the fruits added to the beers give new characteristics to the drink, in addition to guaranteeing greater oxidative stability, acting in the shelf life of the product, due to the bioactive potential characteristic of this raw material. In this sense, the fruit of the mandacaru (Cereus jamacaru DC.), typical of the Caatinga of Northeast Brazil, rich in fermentable sugars, minerals and antioxidant substances, appears as a promising alternative for application in artisanal beers, aiming to impart aromatic complexity and enhance the bioactive character of the drink. The objective of this work was to elaborate and verify the influence of the addition of the mandacaru fruit in the formation of volatile compounds, in the antioxidant activity and phenolic composition of an artisanal wheat beer. Three beer formulations were prepared using different concentrations of the adjunct, calculated in relation to the volume of the wort: 100 g/L (Beer A), 200 g/L (Beer B) and 300 g/L (Beer C), in addition to a control beer. The results showed that the addition of the mandacaru fruit increased the concentration of ethanol, glycerol and organic acids, obtained by HPLC. Beers A, B and C had similar concentrations of ethanol (29.5 g/L). Beer C stood out in the production of glycerol (5.4 g/L) and beer B in the concentration of organic acids (7 g/L). Sixty-one volatile compounds were identified by GC-MS, more abundant in beers added with mandacaru fruit, including some important esters for the aromatic characterization of beers, such as ethyl acetate, phenethyl acetate and ethyl hexanoate. Phenethyl alcohol and 2- methyl-1-butanol were more abundant in the control beer. Other groups of volatile compounds such as terpenes, hydrocarbons, phenols and sulfur compounds were more abundant in beers added to the fruit. The positive impact of enrichment of beers with mandacaru fruit was verified on the antioxidant activity evaluated by the DPPH, ABTS and FRAP methods and on the content of phenolic compounds, the latter being higher for C beer (25.35 g/L). Sixteen phenolic compounds were identified, belonging to the class of flavonoids, phenolic acids and tannins, with beer C being highlighted in the concentration of flavonoids, such as epicatechin (3.86 g/L) and myricetin (1.78 g/L) and in phenolic acids, such as gallic acid (6.22 g/L) and caffeic acid (0.13 g/L). Procyanidin B2, belonging to the tannin class, was the most abundant phenolic compound in the evaluated samples, except for beer B. The results of this study suggest that the addition of mandacaru fruit resulted in an increase in the concentration of ethanol, glycerol and organic acids. of beers, as well as in the content of phenolic compounds and consequently in the antioxidant activity, improving the bioactive characteristics of the drink. The volatile composition of the beers was also affected with the addition of the mandacaru fruit, resulting in a greater abundance of esters, which act mainly through the aromatic profile, terpenes, hydrocarbons and among other groups of volatile compounds. Thus, the mandacaru fruit demonstrated its potential to enrich the volatile and phenolic composition of beers, serving as a promising alternative for application as an adjunct in craft beers.