Mechanisms of acetic acid resistance in spoilage yeasts

目前，世界粮食产量的三分之一因变质而损失。因此，发展大规模保存食品原料的改进方法非常重要。许多被批准用于食品、饮料和药品的化学防腐剂都是弱有机酸。这些都是天然化合物，有很长的安全使用历史，立法，特别是在欧盟，不太可能批准大规模使用更新、更有效的防腐剂。这些弱酸的一个主要缺点是，为了抑制腐烂霉菌和酵母菌的生长，必须经常高水平地使用它们。因此，腐败酵母菌对这些防腐剂的抗药性是阻碍许多食品和饮料中防腐剂水平降低的主要障碍。我们一直在解开腐败酵母的弱酸防腐剂系统，现在已经在这一领域确立了世界领先地位。这个项目的重点是了解腐烂的酵母如何对醋酸产生抵抗力，这一了解将有助于食品行业使用较低水平的醋酸盐进行保存，从而帮助满足消费者对保存较少的产品的需求，同时在面对日益严格的使用有限数量的防腐剂的立法的情况下保持微生物的安全和稳定。还将帮助葡萄酒行业防止在葡萄酒发酵的初期阶段醋酸盐对酵母菌的抑制。

Currently one third of world food production is lost through spoilage. It is therefore very important to develop improved methods for the large-scale preservation of food materials. Many of the chemical preservatives approved for use in foods, beverages and pharmaceuticals are weak organic acids. These are natural compounds with a long history of apparently safe use and legislation, particularly in the EU, is unlikely to approve large-scale use of newer, more effective preservatives. A major drawback with these weak acids is that they must often be used at high level in order to inhibit growth of spoilage moulds and yeasts. Thus the resistance of spoilage yeasts to these preservatives is the major obstacle preventing a lowering of the preservative levels in many foods and beverages. We have been unravelling the weak acid preservative resistance systems of spoilage yeasts, having now established a world lead in this area. This project is focussed on understanding how spoilage yeasts become resistant to acetic acid, an understanding that will help the food industry use lower levels of acetate in preservation, thus helping to satisfy consumer demand for less-heavily preserved products, whilst maintaining microbiological safety and stability in the face of ever-tightening legislation on the use of a limited number of preservatives.It will also help the wine industry prevent acetate inhibition of the yeast during the initial stages of wine fermentations.