Antioxidant Capacity and Total Phenol Content in Hop and Malt Commercial Samples

Abstract

The antioxidant properties of commercial hops and malted barley were evaluated by electroanalytical methods and compared with spectrophotometric methods. Hop group showed better antioxidant capacity and total phenols content (TPC) values than malt group. The highest electrochemical Index (EI) was observed for HCO hop sample. Electrochemical Index (EI) showed a good Pearson correlation with ABTS (2,2′‐azino‐bis (3‐ethylbenzothiazoline‐6‐sulphonic acid)), DPPH (2,2‐diphenyl‐1‐picrylhydrazyl), and TPC, being of 0.85, 0.77 and 0.86 respectively for hop samples. While for the malt samples were 0.96, 0.69 and 0.49, respectively. The samples were compared to each other within each group and statistical differences can be observed, p<0.05. Therefore, the electroanalytical tools showed to be practical and easy to evaluate the antioxidant properties of hop and malt samples. The results may contribute to the selection of raw material for brewing and therefore with the quality of one of beverage one most consumed around the world.

Correlation of polyphenol content and antioxidant capacity of selected teas and tisanes from Brazilian market

“…The EI strongly depended on both TF and AOA, and the TP presented a very strong correlation with the real antioxidant capacity of the products as determined by the EI. Similar trends were found in studies on other food matrices (Oliveira Neto et al, 2017a, 2017b, 2017cShao et al, 2018) and phytomedicines (Leite et al, 2018;Moreno et al, 2019). In Figure 5, the decision tree presents the classification of all products results in either simple or composed.…”

“…Electrochemical and colorimetric assays have been considered useful techniques to evaluate the redox features of complex samples such as foodstuff and nutraceuticals (Arteaga et al, 2012;Macêdo et al, 2017;Oliveira Neto et al, 2017a, 2017b, 2017cLeite et al, 2018;Lino et al, 2014;Oliveira-Neto et al, 2016). Therefore, both CV and SWV results revealed that the aqueous extracts presented kinetic and thermodynamic processes which correlate to antioxidant potential.…”

Electrochemical Methods to Evaluate the Antioxidant Activity and Capacity of Foods: A Review

“…Generally, the peak current is used to estimate the antioxidant capacity or the concentration of antioxidants, whereas the peak potential can be used to identify the type of antioxidants. Applications of this technique for the measurement of antioxidants has been reported for tea [101][102][103][104], fruits, peels and pulps [78,[105][106][107][108][109], wines [67,[110][111][112][113][114][115], spices [116], herbal, plants or roots [79 ,87, 117, 118], dry fruits [119,120], honey [121] and propolis [75,122,123], meats [124], ginger [90], medicinal plant's leave and husk [125,126], beverage [127], coffees [128] and green coffee beans [62], fish oils [129], hops and malt [130] and algae [131].…”

“…The antioxidant activity has been determined by SWV in red wines [46,134], garlic samples [141], green and black tea [135,142], edible oils/ extra-virgin olive oils [143,144], plant/herbal extracts [79,145], fruit extract [119,146], saffron extract [147], tea and coffee samples [69,148], roots of Echinacea purpurea [118], bioactive compound in capsicum sp. extract [138], olive leaf extract [149], commercial hop and malt samples [130], vitamins E and K in food supplement [150], sesamol in sesame oil [151], and others.…”