柠檬酸（citric acid，CA）是一种天然的有机酸，在成熟的柠檬、百香果、红树莓等柠檬酸型水果中含量高，导致此类水果酸感尖锐，加工产品的适口性、感官品质会受到不同程度的影响。柠檬酸可以被乳酸菌利用生成双乙酰、乙偶姻和丁二醇等香气化合物，也可以在酵母菌内转化为醇、乙醛酸、琥珀酸等多种代谢产物。不同的柠檬酸降解途径赋予柠檬酸型水果加工产品的品质和风味有显著差异。该研究详细地阐述了乳酸菌、酵母菌生物降解柠檬酸的途径及主要代谢产物，分析了pH、碳源两种因素对生物降解柠檬酸的影响及生物降解柠檬酸在果汁、果酒等加工中的应用，指出了限制乳酸菌和酵母菌用于生物降解柠檬酸的条件，旨在为柠檬酸降解的研究及应用提供理论依据和技术参考。

Citric acid (CA) is a kind of natural organic acid, which has a high content in mature citric acid fruits such as lemon, passion fruit and red raspberry, resulting in sharp acidity of such fruits, and the palatability and sensory quality of processed products will be affected to varying degrees. Citric acid can be used by lactic acid bacteria to produce aromatic compounds such as diacetyl, acetoin and butanediol, and can also be transformed into multiple metabolites such as alcohol, acetaldehyde acid and succinic acid in yeast. The quality of citricacid type fruit processing products and flavor brought by different degradation pathways of citric acid have significant differences. In this paper, the pathways and metabolites of citric acid biodegradation by lactic acid bacteria and yeast were described in detail. The effects of pH and carbon source on citric acid biodegradation and the application of citric acid biodegradation in the processing of fruit juice and fruit wine were analyzed. The conditions limiting the use of lactic acid bacteria and yeast in citric acid biodegradation were pointed out, so as to provide theoretical basis and technical reference for the research and application of citric acid biodegradation.

中央高校基本科研业务费专项资金项目（2572018BA07）；东北林业大学大学生创新项目（202010225138）