Department of Food Science and Technology, Hebei Agricultural University, Baoding, Hebei, China.
Advanced Therapies Group, School of Dentistry, Cardiff University, Cardiff, UK.
Compr Rev Food Sci Food Saf. 2024 Jul;23(4):e13364. doi: 10.1111/1541-4337.13364.
Kefir milk, known for its high nutritional value and health benefits, is traditionally produced by fermenting milk with kefir grains. These grains are a complex symbiotic community of lactic acid bacteria, acetic acid bacteria, yeasts, and other microorganisms. However, the intricate coexistence mechanisms within these microbial colonies remain a mystery, posing challenges in predicting their biological and functional traits. This uncertainty often leads to variability in kefir milk's quality and safety. This review delves into the unique structural characteristics of kefir grains, particularly their distinctive hollow structure. We propose hypotheses on their formation, which appears to be influenced by the aggregation behaviors of the community members and their alliances. In kefir milk, a systematic colonization process is driven by metabolite release, orchestrating the spatiotemporal rearrangement of ecological niches. We place special emphasis on the dynamic spatiotemporal changes within the kefir microbial community. Spatially, we observe variations in species morphology and distribution across different locations within the grain structure. Temporally, the review highlights the succession patterns of the microbial community, shedding light on their evolving interactions.Furthermore, we explore the ecological mechanisms underpinning the formation of a stable community composition. The interplay of cooperative and competitive species within these microorganisms ensures a dynamic balance, contributing to the community's richness and stability. In kefir community, competitive species foster diversity and stability, whereas cooperative species bolster mutualistic symbiosis. By deepening our understanding of the behaviors of these complex microbial communities, we can pave the way for future advancements in the development and diversification of starter cultures for food fermentation processes.
开菲尔奶因其高营养价值和健康益处而闻名，传统上是通过用开菲尔粒发酵牛奶制成的。这些颗粒是一种复杂的共生群落，其中包括乳酸菌、醋酸菌、酵母和其他微生物。然而，这些微生物群落内部的共生机制仍然是一个谜，这给预测它们的生物学和功能特性带来了挑战。这种不确定性常常导致开菲尔奶的质量和安全性存在差异。
本综述深入探讨了开菲尔粒的独特结构特征，特别是其独特的中空结构。我们提出了关于其形成的假设，这似乎受到社区成员的聚集行为及其联盟的影响。在开菲尔奶中，代谢物的释放驱动了一种系统的定殖过程，协调了生态位的时空重排。我们特别强调开菲尔微生物群落内的动态时空变化。从空间上看，我们观察到不同部位的物种形态和分布存在差异。从时间上看，本综述强调了微生物群落的演替模式，揭示了它们不断变化的相互作用。
此外，我们探讨了形成稳定群落组成的生态机制。这些微生物体内的共生和竞争物种相互作用，确保了动态平衡，促进了群落的丰富度和稳定性。在开菲尔群落中，竞争物种促进了多样性和稳定性，而合作物种则促进了互利共生。通过深入了解这些复杂微生物群落的行为，我们可以为未来食品发酵过程中发酵剂的开发和多样化铺平道路。
