# Effect of Domestic Cooking of Hull-Less Barley Genotypes on Total Polyphenol Content and Antioxidant Activity

## TL;DR

This study examines how cooking affects the polyphenol content and antioxidant activity of hull-less barley, finding that some cooking methods can increase antioxidant activity.

## Contribution

The novelty lies in evaluating the impact of common domestic cooking methods on polyphenol content and antioxidant activity in different hull-less barley genotypes.

## Key findings

- Cooking methods like boiling and microwave heating reduced total polyphenol content in hull-less barley.
- Antioxidant activity measured by DPPH increased after cooking for most barley genotypes.
- Insoluble polyphenol antioxidant activity decreased across most genotypes after thermal treatment.

## Abstract

Barley is a good source of dietary fibre, vitamins, and minerals. Moreover, it is a source of polyphenols, which recently have been studied for their antioxidant properties. Barley generally is not eaten in its raw form, and the necessary processing influences the polyphenol content. This study evaluated the content of polyphenol compounds and antioxidant activity before and after thermal treatment typical for that carried out in households (i.e., boiling and subsequent microwave heating). Six genetic materials of hull-less barley were chosen for this study. The results showed that all tested barley genotypes were good sources of polyphenols. The studied thermal processes led to certain reductions in polyphenol content. The antioxidant activity of soluble phenolic compounds and the effects of heat treatment, as analysed by Trolox equivalent antioxidant activity (TEAC) and 2,2-diphenyl-1-picrylhydrazyl assay (DPPH) methods, differed. In the case of the DPPH method, the boiling and subsequent microwave heating indicated growth in antioxidant activity for almost all genotypes. When using the TEAC method, the results were not so clear, as the indicated activity both increased and declined. In the case of insoluble polyphenols, the antioxidant activity decreased for almost all genotypes regardless of the measurement method used.