9. Selection and development of new brewing yeasts with superior industrial phenotypes

Alicia Gutierrez Linares (1), Veerle Saels (1), Jan Steensels (1), Kevin Verstrepen (1); (1) KU Leuven CMPG & VIB Lab for Systems Biology, Leuven, Belgium

Technical Session 3: Yeast Biotechnology
Sunday, August 14  •  9:45–11:30 a.m.
Plaza Building, Concourse Level, Governor’s Square 15

Yeasts, and more specifically Saccharomyces cerevisiae, possess many properties that make them suitable for biotechnological applications and industrial fermentations. However, many strains currently used in industry, especially in beer brewing, are used because of historical grounds, rather than being selected for having the most optimal characteristics. While nature harbors a huge yeast diversity, the specific conditions found in industrial fermentation processes require an ideal combination of many yeast properties that are not habitually in nature, such as fermentation vigor, high ethanol production and an attractive aroma profile. Nowadays, several innovative yeast improvement strategies, such as hybridization, have been used to create novel yeasts with advantageous features. In this study, we carried out high-throughput screening of 600 natural and industrial yeast strains for a broad plethora of industrially relevant yeast characteristics, such as stress tolerance (ethanol, temperature, osmotic pressure, etc.), fermentation performance and aroma production, to select the most interesting parental strains for further breeding. Our main scope was to develop novel superior brewer’s yeast strains through different selection methods and breeding approaches, such as direct mating and large-scale genome shuffling. Mimicked beer fermentation performed with the developed hybrids revealed that this approach successfully developed new yeast variants with improved aroma profile and increased fermentation capacity, which can directly be implemented in industry. Moreover, the developed hybrids form the perfect tool for investigation of genetic underpinnings of industrially relevant yeast properties. For example, new genes and superior alleles involved in the production of fruity acetate esters were identified. This new genetic information, in turn, will lead to the development of new, more targeted yeast improvement strategies, such as marker-assisted breeding.

Alicia Gutierrez Linares acquire her B.S. degree in biology at the University of Valencia (Spain) in 2007 and M.S. degree in food science and engineering at Polytechnic University of Valencia (Spain) in 2009. She did an international Ph.D. degree in food science, technology and management at Polytechnic University of Valencia (Spain), and she carried out the study at the Institute of Agrochemistry and Food Technology regarding “Nitrogen Metabolism in Wine Yeast During Alcoholic Fermentation: Effect on Growth, Fermentation Activity and Aroma Production.” Her first postdoc with a Marie Curie Fellowship was at Carlsberg Research Center (Denmark, Copenhagen) on “Non-conventional Yeasts and Their Aroma Production in Fermented Beverages.” In November 2015, Alicia joined CMPG Lab for Genetics and Genomics at KU Leuven (Belgium), led by Prof. Kevin Verstrepen, as a postdoc.