This review reports on the effects of fermentation on the chemical constituents and antioxidant activity of plant-based food materials. Fermentation involves a series of reactions that modify the chemical components of the substrate. It could be considered a tool to increase the bioactive compounds and functional properties of food plant materials. Oxidative damage is key to the progression of many human diseases, and the production of antioxidant compounds by fermentation will be helpful to reduce the risk of these diseases. Fermentation also can improve antioxidant activity given its association with increased phytochemicals, antioxidant polysaccharides, and antioxidant peptides produced by microbial hydrolysis or biotransformation. Additionally, fermentation can encourage the breakdown of plant cell walls, which helps to liberate or produce various antioxidant compounds. Overall, results indicated that fermentation in many cases contributed to enhancing antioxidants’ content and antioxidant capacity, supporting the fermentation use in the production of value-added functional food. This review provides an overview of the factors that impact the effects of fermentation on bioactive compound composition and antioxidant activity. The impacts of fermentation are summarized as a reference to its effects on food plant material.

Grains are an energy source for human beings, and the two main components—starch and protein—determine the application of grains in food. The structure and properties of starch play a decisive role in determining processing characteristics, nutritional properties, and application in grain-based foods. The interaction of proteins with starch greatly affects the structure, physicochemical, and digestive properties of the starch matrix. Scientists have tried to apply this effect to create foods tailored to specific needs. Therefore, studying the effect of protein on the structure and properties of starch in the starch–protein complexes will help in designing personalized and improved starch-based food. This paper reviews the latest research about the effects of endogenous and exogenous proteins on the structure and properties of starch, as well as factors influencing the interaction between protein and starch. This includes investigations of the chain and aggregation structure of proteins with starch, as well as assessments of impacts on thermal properties, rheology, gel texture properties, hydration properties, aging, and digestion. In addition, particular examples illustrating the effects of protein–starch interaction on starch properties in various foods are discussed, providing a reference for designing starch–protein foods that are rich in terms of nutrition and easier to process.

Fermentation is one of the most economical and safe methods to improve the nutritional value, sensory quality and functional characteristics of raw materials, and it is also an important method for cereal processing. This paper reviews the effects of microbial fermentation on cereals, focusing on their nutritional value and health benefits, including the effects of fermentation on the protein, starch, phenolic compounds contents, and other nutrient components of cereals. The bioactive compounds produced by fermented cereals have positive effects on health regulation. Finally, the future market development of fermented cereal products is summarized and prospected.

Food fermentation is driven by microbial interactions. This article reviews the types of microbial interactions during food fermentation, the research strategies employed, and their impacts on the quality of fermented foods. Microbial interactions primarily include mutualism, commensalism, amensalism, and competition. Based on these interaction patterns, the safety, nutritional composition, and flavor quality of food can be effectively improved. Achieving precise control of fermented foods’ qualities via microbial interaction remains a critical challenge. Emerging technologies such as high-throughput sequencing, cell sorting, and metabolomics enable the systematic analysis of core microbial interaction mechanisms in complex systems. Using synthetic microbial communities and genome-scale metabolic network models, complicated microbial communities can be effectively simplified. In addition, regulatory targets of food quality can be precisely identified. These strategies lay a solid foundation for the precise improvement of fermented food quality and functionality.

Postbiotics, as the metabolic products and cellular components of probiotics, possess the characteristics of being non-living yet retaining biological activity. Postbiotics have unique advantages such as high stability, good security, and a clear target of action. In recent years, they have attracted extensive attention due to their potential roles in immune regulation, anti-inflammation, antioxidation, antibacterial activity, and improving intestinal health. This article systematically reviews the composition of postbiotics and their diversity in fermented foods, with a focus on the impact of different inactivation methods (thermal and non-thermal inactivation) on their biological activities. Many studies have shown that the choice of inactivation method directly affects the immune regulation, anti-inflammatory, and antioxidative functions of postbiotics. Additionally, this review summarizes the application potential of postbiotics in the food industry, the field of medicine and food homology, pet food, and animal breeding, and points out the challenges existing in current research. Future studies need to focus on optimizing inactivation methods to maximize the biological efficacy of postbiotics, thereby promoting the precise application of postbiotics in various fields.

Phenols are natural compounds with considerable bioactivities. However, the low bioavailability and chemical instability of phenols limit their biological functions. This review summarizes recent progress in phenol delivery systems that account for the specific physiological conditions of the gastrointestinal tract. It focuses on the delivery materials for intestinal targeting and the synergistic benefits of co-encapsulating phenols with other functional ingredients. To achieve targeted release of phenols in the digestive tract, factors such as pH, digestive enzymes, and gut microbiota should be fully considered in delivery system designing. Materials like chitosan, sodium alginate, pectin, and guar gum offer effective protection and targeted delivery of phenols due to their pH sensitivity and enzyme-degradable properties. Co-delivery systems that combine phenols with carotenoids or probiotics improve the functional properties of phenols, such as antioxidant activity, anti-inflammatory effect, and regulation of gut microbiota. Probiotics can enhance phenolic compound absorption and probiotic survival in a phenolic–probiotic co-encapsulation system through debonding, bioconversion, and synergistic effects.