Wu Lianqun, Yang Zhenying, Zhang Ying, Li Ling, Tan Chunli, Pan Lixia, Wu Yanping, Zhong Kai, Gao Hong
College of Biomass Science and Engineering, Sichuan University, Chengdu 610065, China.
Sichuan Teway Food Group Co., Ltd., Chengdu 610000, China.
Foods. 2025 Jan 7;14(2):157. doi: 10.3390/foods14020157.
The quality of Sichuan paocai in natural fermentation is often inconsistent due to the complexity of its microbial community and environmental influences. To address this, dominant microbial strains were selectively inoculated to improve the product's quality and safety. However, vacuum freeze-drying, commonly used to prepare direct vat set (DVS) starters, can significantly damage strains due to freezing stress. This study aimed to optimize a freeze-drying protection system for and to enhance their survival. Using response surface methodology, combinations of cryoprotectants were evaluated. A formulation comprising skim milk powder, glycerol, sucrose, and L-proline significantly improved strain viability after lyophilization, outperforming single cryoprotectants. Further investigation into storage conditions revealed that low temperatures (-20 °C) provided the best preservation for DVS starters. Furthermore, the optimized DVS starters demonstrated excellent fermentation performance in Sichuan paocai, enhancing its color, flavor, and sensory quality compared to natural fermentation. These findings offer a reliable freeze-drying protection strategy for survival and viability of and .
由于其微生物群落的复杂性和环境影响，自然发酵的四川泡菜质量往往不稳定。为了解决这个问题，通过选择性接种优势微生物菌株来提高产品质量和安全性。然而，常用于制备直投式发酵剂（DVS）的真空冷冻干燥会因冷冻胁迫而显著损害菌株。本研究旨在优化针对[具体菌株名称未给出]的冷冻干燥保护系统，以提高其存活率。采用响应面法评估了冷冻保护剂的组合。一种包含脱脂奶粉、甘油、蔗糖和L-脯氨酸的配方显著提高了冻干后菌株的活力，优于单一冷冻保护剂。对储存条件的进一步研究表明，低温（-20°C）为DVS发酵剂提供了最佳保存条件。此外，优化后的DVS发酵剂在四川泡菜中表现出优异的发酵性能，与自然发酵相比，提升了泡菜的色泽、风味和感官品质。这些发现为[具体菌株名称未给出]的存活和活力提供了可靠的冷冻干燥保护策略。
