The Potential of Traditional Norwegian KVEIK Yeast for Brewing Novel Beer on the Example of Foreign Extra Stout.

Adam Głowacki,Alan Gasiński,Justyna Paszkot,Przemysław Leszczyński,Witold Pietrzak,Joanna Kawa-Rygielska,Kinga Adamenko

doi:10.3390/biom11121778

Adam Głowacki, Alan Gasiński + Show 5 more

Open Access

https://doi.org/10.3390/biom11121778

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Abstract

The development of craft brewing has spurred huge interest in unusual and traditional technologies and ingredients allowing the production of beers that would fulfil consumers’ growing demands. In this study, we evaluated the brewing performance of traditional Norwegian KVEIK yeast during the production of Foreign Extra Stout beer. The content of alcohol of the KVEIK-fermented beer was 5.11–5.58% v/v, the extract content was 5.05–6.66% w/w, and the pH value was 4.53–4.83. The KVEIK yeast was able to completely consume maltose and maltotriose. The mean concentration of glycerol in KVEIK-fermented beers was higher than in the control sample (1.51 g/L vs. 1.12 g/L, respectively). The use of KVEIK-type yeast can offer a viable method for increasing the concentration of phenolic compounds in beer and for boosting its antioxidative potential. The beers produced with KVEIK-type yeast had a total phenol content of 446.9–598.7 mg GAE/L, exhibited antioxidative potential of 0.63–1.08 mM TE/L in the DPPH• assay and 3.85–5.16 mM TE/L in the ABTS•+ assay, and showed a ferric ion reducing capacity (FRAP) of 3.54–4.14 mM TE/L. The KVEIK-fermented bears contained various levels of volatile compounds (lower or higher depending on the yeast strain) and especially of higher alcohols, such as 3-metylobutanol, 2-metylobutanol, and 1-propanol, or ethyl esters, such as ethyl acetate or decanoate, compared to the control beers. In addition, they featured a richer fruity aroma (apricot, dried fruit, apples) than the control beers fermented with a commercial US-05 strain.

Highlights

The alcohol content of the KVEIK-fermented beers ranged from 3.56% v/v (HVK) to 3.87% v/v (VK2)
In their study, the samples were fermented at higher temperatures than in the present research, which may point to a higher temperature optimum of KVEIK yeast compared to the standard yeast strains
There were no significant differences in the consumption of glucose, maltose, and maltotriose between KVEIK yeast strains and the commercial yeast strain, which indicates that the yeast tested fulfilled an important technological criterion

Summary

Introduction

Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. The Norwegian yeast strains of the KVEIK type can be divided into two groups according to their geographic origin, i.e., those from the north or south of the Jostedal glacier. In Scandinavian countries, these yeast strains have been for years used locally to produce traditional beers, such as konnjøl, stjørdalsøl, or maltøl [1]. The yeast suspension is first dipped in an oval-shaped wooden construction, in ash or flour, and dried. The first constructions of this type date back to the onset of the 17th century [6]

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