Brewing potential of strains of the boreal wild yeast Mrakia gelida

Riikka Linnakoski (Corresponding Author), Tuula Jyske, Ronja Eerikäinen, Pyry Veteli, Marta Cortina-Escribano, Frederico Magalhães, Eila Järvenpää, Lotta Heikkilä, Mathias Hutzler, Brian Gibson

Research output: Contribution to journalArticleScientificpeer-review

3 Citations (Scopus)


Demand for low- or non-alcoholic beers has been growing in recent years. Thus, research is increasingly focusing on non-Saccharomyces species that typically are only able to consume the simple sugars in wort, and therefore have a limited production of alcohol. In this project, new species and strains of non-conventional yeasts were sampled and identified from Finnish forest environments. From this wild yeast collection, a number of Mrakia gelida strains were selected for small-scale fermentation tests and compared with a reference strain, the low-alcohol brewing yeast Saccharomycodes ludwigii. All the M. gelida strains were able to produce beer with an average of 0.7% alcohol, similar to the control strain. One M. gelida strain showing the most promising combination of good fermentation profile and production of desirable flavor active compounds was selected for pilot-scale (40 L) fermentation. The beers produced were matured, filtered, carbonated, and bottled. The bottled beers were then directed for in-house evaluation, and further analyzed for sensory profiles. The beers produced contained 0.6% Alcohol by volume (ABV). According to the sensory analysis, the beers were comparable to those produced by S. ludwigii, and contained detectable fruit notes (banana and plum). No distinct off-flavors were noted. A comprehensive analysis of M. gelida’s resistance to temperature extremes, disinfectant, common preservatives, and antifungal agents would suggest that the strains pose little risk to either process hygiene or occupational safety.

Original languageEnglish
Article number1108961
JournalFrontiers in Microbiology
Publication statusPublished - 9 Feb 2023
MoE publication typeA1 Journal article-refereed


  • brewing yeast
  • Finnish forests
  • low-alcohol beer
  • non-Saccharomyces
  • tree


Dive into the research topics of 'Brewing potential of strains of the boreal wild yeast Mrakia gelida'. Together they form a unique fingerprint.

Cite this