Brewing Rutin-Enriched Lager Beer with Buckwheat Malt as Adjuncts

Abstract

Brewing with buckwheat as an ingredient has been proven to be successful in several previous studies. However, few studies have focused on the effects of buckwheat on the rutin content and antioxidant activity of beer. In order to develop a lager beer with high rutin content and desirable sensory characteristics, tartary buckwheat malt was used as a brewing adjunct. The results showed that the rutin-degrading enzyme was the key factor affecting the rutin content in the wort and beer. Compared to beer made using the common mashing method, the rutin content in the buckwheat beers produced using an improved mashing method was approximately 60 times higher. The total flavonoid contents in buckwheat beers also depended strongly on the mashing methods, ranging from 530.75 to 1,704.68 mg QE/l. The rutin-rich beers also showed better oxidative stability during forced-aging. Meanwhile, the buckwheat beers were found to be acceptable in terms of the main quality attributes, flavor, and taste.

Keywords: Buckwheat malt; flavonoid compounds; functional beer; oxidative stability; rutin.