Optimisation of Lactobacillus fermentation conditions and its application in the fermentation of salt-free sauerkraut

• Published in: Frontiers in microbiology Vol. 15; p. 1482163
• Main Authors: Wang, Wenlun, Li, Wenbing, Huang, Yan, Yang, Ying, Liu, Hui, Yu, Chaohang, Yuan, Qing, He, Lianmin, Hu, Qianmin, Li, Ye, Meng, Taoyan, Chen, Huanhuan, Liao, Jiabi, Chen, Ou, Yu, Shirui, Zhang, Feng
• Format: Journal Article
• Language: English
• Published: Frontiers Media S.A 21.10.2024
• Subjects: central composite design; lactic acid bacteria; Microbiology; Plackett-Burman experiment; probiotics; salt-free sauerkraut
• ISSN: 1664-302X; 1664-302X
• DOI: 10.3389/fmicb.2024.1482163

To identify what are the dominant lactic acid bacteria (LAB) involved in the fermentation of salt-free sauerkraut, and optimize its industrial culture conditions, we isolated and identified a strain of LAB, which is referred to as Lactobacillus sp. DF_001, with the preservation number CCTCC NO: M20232593, from five different regions in Guizhou Province. Industrial culture conditions were optimized using Plackett-Burman and Central Composite design experiments, and the potential role of this LAB in salt-free sauerkraut fermentation was validated. Bioproduction was optimal with a culture time of 66 h, starch/water ratio of 1.7% and inoculum of 0.02%, which gave approximately three-fold higher yield than the basal culture medium DeMan-Rogosa-Sharpe medium (MRS). The LAB was used in small-scale industrial experiments. The Dafang LAB significantly enhanced the sensory score of the salt-free sauerkraut products by about 32% compared to the control group. The total acid content increased by about 32% and the sugar and nitrite contents were reduced by 67.27 and 69.58%, respectively. The total number of bacterial colonies decreased by 37.5%. All other indicators complied with the national standard, providing overall the basis to improve salt-free sauerkraut fermentation.