Artisanal beer added of Solanum sessiliflorum pulp: total phenolic compounds and antioxidant activity / Cerveja artesanal adicionada de polpa de Solanum sessiliflorum: compostos fenólicos totais e atividade antioxidante

Brazilian beer market presented remarkable increasement last years. Despite of this, Brazilian Amazon states presented discrete growth, with decreasement in some important states as Amazonas. Cubiu (Solanum sessiliflorum) is a fruiting plant which has been used traditionally by people of the upper Amazon and Orinoco basin as artisanal medicine because of its bioactive molecules' richness. Because of world trend of innovative brewing products as fruit-beers, the aim of this work was to evaluate the composition and antioxidant activity of an artisanal beer added of cubiu. A total of 28 g/L of cubiu's pulp were added to the beer in maturation's phase, incubated at 4 °C for 10 days. Compared to a control assay, the resulting beer presented higher turbidity and soluble protein concentration. Total phenolic compounds concentration (435,93 µgGAE/mL) and antioxidant activity (66,36% of free radicals scavenged) were significantly greater than control assay (p <0,001). The results indicates that a low amount of cubiu's pulp is sufficient to makes the beer functionally antioxidant. The subsequent efforts must to evaluate the acceptance of a beer added of S. sessiliflorum pulp to assessing its market potential.

O mercado brasileiro de cerveja apresentou notável crescimento nos últimos anos. Apesar disso, os estados amazônicos brasileiros apresentaram crescimento discreto, com queda em alguns estados importantes como o Amazonas. Cubiu (Solanum sessiliflorum) é uma planta frutífera que tem sido tradicionalmente utilizada pelos povos do alto Amazonas e da bacia do Orinoco como medicamento artesanal devido à sua riqueza em moléculas bioativas. Devido à tendência mundial de produtos cervejeiros inovadores, como as cervejas de frutas, o objetivo deste trabalho foi avaliar a composição e atividade antioxidante de uma cerveja artesanal adicionada de cubiu. Um total de 28 g/L de polpa de cubiu foram adicionados à cerveja em fase de maturação, incubada a 4 °C por 10 dias. Comparada a um ensaio controle, a cerveja resultante apresentou maior turbidez e concentração de proteína solúvel. A concentração total de compostos fenólicos (435,93 µgGAE/mL) e a atividade antioxidante (66,36% dos radicais livres neutralizados) foram significativamente superiores ao ensaio controle (p <0,001). Os resultados indicam que uma pequena quantidade de polpa de cubiu é suficiente para tornar a cerveja funcionalmente antioxidante. Os esforços subsequentes devem avaliar a aceitação de uma cerveja adicionada de polpa de S. sessiliflorum para avaliar seu potencial de mercado.

Wheat craft beer made from AFB1-contaminated wheat malt contains detectable mycotoxins, retains quality attributes, but differs in some fermentation metabolites.

Levels of aflatoxin B1 (AFB1) were measured during the production of wheat craft beer made with wheat malt contaminated with AFB1 (1.23 µg/kg). A wheat craft beer made with non-contaminated wheat malt was produced for comparison purposes. AFB1 was measured after mashing (malt after the mashing process), and in spent grain (spent grains are filtered to collect the wort - remaining sugar-rich liquid), sweet wort, green beer, spent yeast, and in beer. Physicochemical parameters (pH, titratable acidity, color parameters, total soluble solids), sugars, organic acids, alcohols, and phenolics were evaluated after mashing, and in sweet wort, green beer, and beer samples. Density and yeast counts were determined over 120 h of sweet wort fermentation every 24 h. The AFB1 levels in the final beer were 0.22 µg/L, while the spent grains and spent yeasts contained 0.71 ± 0.17 and 0.11 ± 0.03 µg/kg of AFB1, respectively. AFB1 contamination did not influence the final product's physicochemical parameters, density during fermentation, fructose, or glycerol content. Higher yeast counts were observed during the first 48 h of non-contaminated wheat craft beer fermentation, with higher ethanol, citric acid, and propionic acid contents and lower glucose, malic acid, and lactic acid contents compared with beer contaminated with AFB1. Non-contaminated wheat craft beer also had higher concentrations of gallic acid, chlorogenic acid, catechin, procyanidin A2, and procyanidin B1. AFB1 contamination of wheat malt may not affect basic quality parameters in wheat craft beer but can influence the final product's organic acid and phenolic contents. Our findings show that if wheat craft beer is made with contaminated malt, AFB1 can remain in the final product and may pose a risk to consumers.

Modeling aflatoxin B1 production by Aspergillus flavus during wheat malting for craft beer as a function of grains steeping degree, temperature and time of germination.

This study aimed to model the aflatoxin B1 (AFB1) production by A. flavus in wheat grains during malting for craft beer. A total of sixty-four different combinations of grains steeping degree (ST; 41, 43, 45 and 47%), temperature (13, 15, 17 and 19 °C) and time of germination (48, 72, 96 and 120 h), comprising the range of malting conditions that allow the production of quality malt, were assayed. AFB1 was produced in a range of 15.78 ± 3.54 µg/kg (41% ST, 13 °C for 48 h) to 284.66 ± 44.34 µg/kg (47% ST, 19 °C for 120 h). The regression model showing an acceptable fit to the experimental data (adjusted R2 0.84) for AFB1 as a function of grains steeping degree, temperature and time of germination. Results showed that AFB1 levels in wheat malt increase with increase of the temperature or time of germination. Within the range of tested malting conditions, no significant effects were observed for steeping degree on AFB1 levels in wheat malt. The generated model is useful to estimate the AFB1 levels in wheat malt. Findings highlight overall that if wheat grains are contaminated with A. flavus, AFB1 might be produced in malt in levels above the limits set by regulatory agencies, regardless the steeping conditions used.

Production of aflatoxin B1 and B2 by Aspergillus flavus in inoculated wheat using typical craft beer malting conditions.

The production of aflatoxin (AF) B1 and B2 was determined during malting of wheat grains artificially contaminated with a toxigenic A. flavus strain (CCDCA 11553) isolated from craft beer raw material. Malting was performed in three steps (steeping, germination and kilning) following standard Central European Commission for Brewing Analysis procedures. AFB1 and AFB2 were quantified in eleven samples collected during the three malting steps and in malted wheat. Both, AFB1 and AFB2 were produced at the beginning of steeping and detected in all samples. The levels of AFB1 ranged from 229.35 to 455.66 µg/kg, and from 5.65 to 13.05 µg/kg for AFB2. The AFB2 increased during steeping, while no changes were observed in AFB1. Otherwise, AFB1 decreased during germination and AFB2 did not change. AFB1 and AFB2 increased after 16 h of kilning at 50 °C and decreased at the end of kilning, when the temperature reached 80 °C. The levels of AFB1 wheat malt were lower than those detected in wheat grains during steeping; however, levels of both AFB1 (240.46 µg/kg) and AFB2 (6.36 µg/kg) in Aspergillus flavus inoculated wheat malt exceeded the limits imposed by the regulatory agencies for cereals and derived products.