Author(s): Pereira, Maria João ; Santos, Diana ; Oliveira, Ana Isabel ; Pinho, Cláudia
Date: 2024
Persistent ID: http://hdl.handle.net/10400.22/25782
Origin: Repositório Científico do Instituto Politécnico do Porto
Subject(s): Craft beer; Antioxidant activity; Phenolic compounds
The antioxidant potential of craft beer (CB) may be due to high quality of the raw materials (water, malt, hop and yeast) and traditional techniques. The scarcity of studies evaluating the antioxidant potential of CB highlights the relevance of thisstudy. In vitroevaluation of the antioxidant activity of aqueous extracts of Portuguese and Spanish CB. Experimental study using six CB with different styles: Milk Stout (EL-MS), India Pale Ale (EL-IPA, ALM-IPA), Imperial Stout (EME-IS), Oatmeal Stout (ALM-OS), Pilsner (EL-P), Munich Dunkell (B-MD) and two industrial beers, Pilsner (S-P) and Munish Dunkell (S-MD). The pH, acidity content (AC) and total phenolic compounds (TPC) were determined. The antioxidant capacity was assessed using 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and the hydrogen peroxide (H2O2) assays, expressed in concentration for 50% activity inhibition (IC50). One-way ANOVA and Student’s t-test were used for statistical analysis in GraphPad®Prism8.0 software, with a significance level of 0.05. The pH of the beers varied between 3.89±0.00-4.78±0.05 and AC between 0.13±0.01-0.44±0.01%. ALM-IPA had the highest TPC value (8.96±0.64mg gallic acid equivalents/g). IPA style presented the lower IC50values in H2O2(ALM-IPA with an IC50=23.54±1.53μg/mL, p<0.05) and ABTS (EL-IPA with an IC50=55.21±4.68μg/mL, p<0.05) assays. The industrial beers have lower TPC values compared to CB (same style, p<0.05), and lower capacity to neutralize the H2O2and ABTS radicals.For Omisore et al. (2005), samples with IC50>50μg/mL are classified as being moderately active, while samples with IC50<50μg/mL have high antioxidant capacity. Also, the results for IPA style are in line with Breda et al. (2022), in which light-colored beers had better antioxidant profiles. However, according to Silva et al. (2022) the best antioxidant profiles were associated with dark beers. The samples showed antioxidant potential, but further tests should be carried out considering the complex underlying antioxidant mechanisms.
