Health-Promoting Components in Fermented Foods: An Up-to-Date Systematic Review.
Plain language summary
While fermented foods have long been produced, a renewed interest has been observed in Western countries. Several reviews have investigated the health benefits of fermented foods, however none of them have discussed the components that form upon fermentation and their possible effect on health. The purpose of this study was to provide a comprehensive review of the health-promoting components of fermentation in order to better understand their role in healthy diets. This systematic review found fermentation increased antioxidant activity of milks, cereals, fruit, vegetables, meat and fish based on 125 analysed articles. Fermentation of different food categories led to varying health benefits including vitamin content, probiotic activity and anti-hypertensive properties. Based on the existing literature, the authors conclude fermented foods should be consumed regularly and recommend they be included in worldwide dietary guidelines.
Fermented foods have long been produced according to knowledge passed down from generation to generation and with no understanding of the potential role of the microorganism(s) involved in the process. However, the scientific and technological revolution in Western countries made fermentation turn from a household to a controlled process suitable for industrial scale production systems intended for the mass marketplace. The aim of this paper is to provide an up-to-date review of the latest studies which investigated the health-promoting components forming upon fermentation of the main food matrices, in order to contribute to understanding their important role in healthy diets and relevance in national dietary recommendations worldwide. Formation of antioxidant, bioactive, anti-hypertensive, anti-diabetic, and FODMAP-reducing components in fermented foods are mainly presented and discussed. Fermentation was found to increase antioxidant activity of milks, cereals, fruit and vegetables, meat and fish. Anti-hypertensive peptides are detected in fermented milk and cereals. Changes in vitamin content are mainly observed in fermented milk and fruits. Fermented milk and fruit juice were found to have probiotic activity. Other effects such as anti-diabetic properties, FODMAP reduction, and changes in fatty acid profile are peculiar of specific food categories.
Bioactivity of soy-based fermented foods: A review.
Biotechnology advances. 2018;37(1):223-238
Plain language summary
Fermented foods are growing in popularity in the West due to their unique flavour and nutritional value. This review investigates the fermentation processes, health-associated bioactive components and underlying mechanisms of the popular fermented soy products Natto, fermented soy milk, Tempeh and soy sauce. Each fermented soy product is summarised based on functional activities. The existing literature points to an overall positive effect on bone health and immune activities. Interestingly, each fermented soy food exhibits different profiles of bioactive components and therefore different mechanisms of action. Based on this review, the authors conclude there is a need for further in-depth human studies with large sample sizes and long-term follow up to better understand these foods benefits and potential toxicity.
For centuries, fermented soy foods have been dietary staples in Asia and, now, in response to consumer demand, they are available throughout the world. Fermentation bestows unique flavors, boosts nutritional values and increases or adds new functional properties. In this review, we describe the functional properties and underlying action mechanisms of soy-based fermented foods such as Natto, fermented soy milk, Tempeh and soy sauce. When possible, the contribution of specific bioactive components is highlighted. While numerous studies with in vitro and animal models have hinted at the functionality of fermented soy foods, ascribing health benefits requires well-designed, often complex human studies with analysis of diet, lifestyle, family and medical history combined with long-term follow-ups for each subject. In addition, the contribution of the microbiome to the bioactivities of fermented soy foods, possibly mediated through direct action or bioactive metabolites, needs to be studied. Potential synergy or other interactions among the microorganisms carrying out the fermentation and the host's microbial community may also contribute to food functionality, but the details still require elucidation. Finally, safety evaluation of fermented soy foods has been limited, but is essential in order to provide guidelines for consumption and confirm lack of toxicity.