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: $ 7.13万
• 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: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=720181
• 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%，部分原因是希腊酸奶进入市场，以及风味混搭、零食选择和酸奶饮料等许多创新。多年来，消费者要求食品更加“天然”。这种需求表现为需要更简单的成分清单，不含食品防腐剂、着色剂和其他添加剂。然而，如果不使用一些不再受到消费者欢迎的质构成分（如淀粉、果胶、明胶等），酸奶质构和口感的控制就很难实现。最有前途的策略是掺入具有调节发酵乳质地的内在能力的细菌菌株。这些菌株产生胞外多糖 (EPS)，它是细菌自然释放的糖酸聚合物（因菌株而异），可增加产品的粘度并减少脱水收缩（乳清从凝胶中排出）。多年来，许多菌株已被鉴定为 EPS 生产者，并成功进行了酸奶生产测试。然而，在工业上，EPS生产菌株的使用主要是在过去十年中通过经验实验引入的。该项目旨在从一组乳酸菌（LAB）中选择新的 EPS 生产菌株。菌株选择将基于已知参与实验室 EPS 生产的特定基因的基因组含量。随后，将在实验室规模上研究一组菌株的酸化率和功能特性。最后，最有希望的候选者将在试点加工设施中进行评估。该项目为博士生和硕士生提供了在工业合作伙伴研究团队实习的独特机会。在该项目结束时，我们希望扩大发酵乳制品的功能，并提供多样化和开发新创新产品的机会。