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

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.

Characteristics of New England India Pale Ale Beer Produced with the Use of Norwegian KVEIK Yeast

“…As shown in this study, the fermentation performance of KVEIK was not clearly explained, which was also reported by the previous studies [ 2 , 4 , 11 ]. One way to point out the fermentation characteristics of KVEIK yeast when provided in mixed culture is to evaluate its monocultures in the ranges of sugars consumption, ethanol, and volatiles production along with the sensory features of final beers.…”

“…However, with the increasing industrialization of Europe coupled with the convenient availability of commercial yeast and pure cultures, the traditional yeast obtained through centuries of selection has lost its importance. Despite this, the recent beer revolution has led to the establishment of a large number of small and medium-sized breweries pursuing new unique flavors and aromas that are not provided by pure cultures obtained in laboratories, e.g., 2-pentanol, ethyl octanoate, ethyl decanoate, and furfural [ 2 ]. Thus, there has been a lot of interest in using unconventional yeasts, such as KVEIK yeast.…”

Yeast Strains and Wort Color as Factors Affecting Effects of the Ethanol Fermentation Process

“…Yeast strains used in fermentation differentiate beers in polyphenol content and antioxidant activity [4]. The reason for these variations may be a different cell wall structure.…”

“…Analysis of ethanol content, real attenuation degree (RDF, % w/w) and apparent attenuation degree (ADF, % w/w), wort extract content (% w/w) and apparent beer extract (% w/w), color (EBC), density (g/cm 3 ) and caloricity (kcal/100 mL) were performed using an oscillating densitometer with a beer analyzer DMA 4500 M (Anton Paar, Graz, Austria) [4]. The beers were shaken for 20 min before analysis using a 358 A laboratory shaker (Elpin Plus, Lubawa, Poland).…”

“…Saccharomyces cerevisiae kveik type yeast used in the production of traditional Norwegian beers and Saccharomyces cerevisiae var. diastaticus used in the production of Belgian saison-style beers are distinct from classic brewer's yeast strains [4,5]. S. cerevisiae kveik yeast shows a high ability to flocculate and rapidly attenuate wort sugars under high temperature conditions (>28 • C).…”