Exopolysaccharides producing strains to control yogurt functionality

产生胞外多糖的菌株可控制酸奶功能

• 批准号: 536620-2018
• 负责人: Turgeon, Sylvie
• 金额: $ 8.65万
• 依托单位: Université Laval
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=699288
• 关键词: Exopolysaccharides; producing; strains; control; yogurt

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.

加拿大酸奶产量在过去十年中增长了60%，部分原因是市场上引入了希腊酸奶，以及许多创新，如风味混搭，零食选择和酸奶饮料。多年来，消费者要求更多的“天然”食品。这一需求转化为对更简单的成分表的需求，不含食品防腐剂，着色剂和其他添加剂。然而，如果不使用一些质构化成分（例如淀粉、果胶、明胶等），则难以实现酸奶质构和发酵的控制。不再受消费者欢迎。最有前途的策略是掺入具有内在能力的细菌菌株来调节发酵乳的质地。这些菌株产生胞外多糖（EPS），胞外多糖是由细菌天然释放的葡聚糖聚合物（其因菌株而异），其增加产品的粘度并减少产品的脱水收缩（乳清从凝胶中排出）。许多菌株已被确定为EPS生产者，并成功地测试了多年来的酸奶生产。然而，在工业中，在过去十年中，主要通过经验性实验引入了产生EPS的菌株的使用。本课题旨在从一组乳酸菌中筛选新型产EPS菌株。菌株选择将基于其已知参与LAB中EPS产生的特定基因中的基因组含量。随后，将在实验室规模上研究一组菌株的酸化速率和功能特性。最后，最有希望的候选人将在试点加工设施进行评估。该项目为博士和硕士学生提供了一个独特的机会，可以在工业合作伙伴研究团队中实习。在该项目结束时，我们预计将扩大发酵乳制品的功能，并提供多样化和开发新的创新产品的机会。