Exopolysaccharides producing strains to control yogurt functionality

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The Canadian yogurt production showed a 60% increase during the last ten years partly due to the introduction of Greek yogurt in the market, and of many innovations such as flavor mash-ups, snacking options and yogurt drink. For many years, consumers have requested more "natural" food products. This demand is translated by the need of a simpler ingredient list with the absence of food preservative, colorants and other additives. However, the control of yogurt texture and mouthfeel is difficult to achieve without the use of some texturizing ingredients (e.g. starch, pectin, gelatin, etc.) that are no longer welcomed by consumers. The most promising strategy is the incorporation of bacterial strains that have intrinsic capabilities to modulate the texture of fermented milk. These strains produce exopolysaccharides (EPS) which are glucidic polymers (which differs from strain to strain) naturally released by the bacteria which increase the viscosity and decrease the syneresis (the expulsion of whey from the gel) of the product. Many strains have been identified as EPS-producers and were successfully tested for yogurt production over the years. However, in the industry, the use of EPS-producing strains was introduced mainly through empiric experimentation during the last decade. This project aims to select new EPS producing strains from a set of lactic acid bacteria (LAB). Strain selection will be based on their genomic content in specific genes known to be involved in EPS production in LAB. Subsequently, a set of strains will be studied at laboratory scale for their acidification rate and functional properties. Finally, the most promising candidate will be evaluated in pilot processing facilities. This project offers a unique opportunity for a PhD and a MSc student to have an internship in the industrial partner research team. At the end of this project, we expect to widen the functionality of the fermented dairy products and offer diversification and opportunities to develop new innovative products.