Although fermentation probably originally developed as a means of preserving food substrates, many fermented foods (FFs), and components therein, are thought to have a beneficial effect on various aspects of human health, and gastrointestinal health in particular. It is important that any such perceived benefits are underpinned by rigorous scientific research to understand the associated mechanisms of action. Here, we review in vitro, ex vivo and in vivo studies that have provided insights into the ways in which the specific food components, including FF microorganisms and a variety of bioactives, can contribute to health-promoting activities. More specifically, we draw on representative examples of FFs to discuss the mechanisms through which functional components are produced or enriched during fermentation (such as bioactive peptides and exopolysaccharides), potentially toxic or harmful compounds (such as phytic acid, mycotoxins and lactose) are removed from the food substrate, and how the introduction of fermentation-associated live or dead microorganisms, or components thereof, to the gut can convey health benefits. These studies, combined with a deeper understanding of the microbial composition of a wider variety of modern and traditional FFs, can facilitate the future optimization of FFs, and associated microorganisms, to retain and maximize beneficial effects in the gut.

尽管发酵最初可能是作为保存食品底物的一种手段而开发的，但许多发酵食品（FF）及其中的成分被认为对人类健康的各个方面，特别是胃肠道健康具有有益的影响。重要的是，任何此类感知到的益处都必须以严格的科学研究为基础，以了解相关的作用机制。在此，我们回顾了体外、离体和体内研究，这些研究深入了解了特定食品成分（包括 FF 微生物和各种生物活性物质）如何促进健康促进活动。更具体地说，我们利用FF的代表性例子来讨论发酵过程中产生或富集功能成分（例如生物活性肽和胞外多糖）、去除潜在有毒或有害化合物（例如植酸、霉菌毒素和乳糖）的机制以及将发酵相关的活的或死的微生物或其成分引入肠道如何带来健康益处。这些研究加上对更广泛的现代和传统 FF 的微生物组成的更深入了解，可以促进 FF 和相关微生物的未来优化，以保留并最大限度地发挥对肠道的有益作用。