This review presents the comprehensive knowledge about the bidirectional relationship between polyphenols and the gut microbiome. The first part is related to polyphenols' impacts on various microorganisms, especially bacteria, and their influence on intestinal pathogens. The research data on the mechanisms of polyphenol action were collected together and organized. The impact of various polyphenols groups on intestinal bacteria both on the whole "microbiota" and on particular species, including probiotics, are presented. Moreover, the impact of polyphenols present in food (bound to the matrix) was compared with the purified polyphenols (such as in dietary supplements) as well as polyphenols in the form of derivatives (such as glycosides) with those in the form of aglycones. The second part of the paper discusses in detail the mechanisms (pathways) and the role of bacterial biotransformation of the most important groups of polyphenols, including the production of bioactive metabolites with a significant impact on the human organism (both positive and negative).

The Interactions between Polyphenols and Microorganisms, Especially Gut Microbiota.

https://digital.csic.es/bitstream/10261/253598/1/Food%20Chem2022-Aleixandre.pdf

Understanding phenolic acids inhibition of α-amylase and α-glucosidase and influence of reaction conditions.

Understanding phenolic acids inhibition of α-amylase and α-glucosidase and influence of reaction conditions

Inorganic nanoparticles (NPs) and natural antioxidant compounds are an emerging trend in the food industry. Incorporating these substances in biobased and biodegradable matrices as polysaccharides (e.g., starch, cellulose, and chitosan) and proteins has highlighted the potential in active food packaging applications due to more significant antimicrobial, antioxidant, UV blocking, oxygen scavenging, water vapor permeability effects, and low environmental impact. In recent years, the migration of metal NPs and metal oxides in food contact packaging and their toxicological potential have raised concerns about the safety of the nanomaterials. In this review, we provide a comprehensive overview of the main biobased and biodegradable polymer nanocomposites, inorganic NPs, natural antioxidants, and their potential use in active food packaging. The intrinsic properties of NPs and natural antioxidant actives in packaging materials are evaluated to extend shelf-life, safety, and food quality. Toxicological and safety aspects of inorganic NPs are highlighted to understand the current controversy on applying some nanomaterials in food packaging. The synergism of inorganic NPs and plant-derived natural antioxidant actives (e.g., vitamins, polyphenols, and carotenoids) and essential oils (EOs) potentiated the antibacterial and antioxidant properties of biodegradable nanocomposite films. Biodegradable packaging films based on green NPs-this is biosynthesized from plant extracts-showed suitable mechanical and barrier properties and had a lower environmental impact and offered efficient food protection. Furthermore, AgNPs and TiO2 NPs released metal ions from packaging into contents insufficiently to cause harm to human cells, which could be helpful to understanding critical gaps and provide progress in the packaging field.

Recent advances in biobased and biodegradable polymer nanocomposites, nanoparticles, and natural antioxidants for antibacterial and antioxidant food packaging applications.

Anthocyanins are water-soluble natural pigments with good antioxidant and antibacterial properties, and their colors are pH sensitive to the environment. At present, the use of plant anthocyanins to prepare active and smart packaging film has attracted increasing attention in the field of food engineering. The use of anthocyanin-based pH-sensitive smart packaging films can not only effectively prolong the shelf life, but also monitor the freshness of food. This review mainly summarizes the mostly used packaging materials, preparation, structural and physicochemical properties, and the applications of anthocyanin-based films as pH-sensitive smart packaging for monitoring food freshness. • Biopolymers and their combinations are widely used in food packaging industry. • Anthocyanins (ACNs) can be used to develop pH-sensitive smart packaging films. • The film preparation technique should ensure the chemical stability of ACNs. • The structural and physicochemical properties of the films are correlated with ACNs. • ACN-based smart packaging facilitates real-time and visual food freshness monitoring. 

Anthocyanin-based pH-sensitive smart packaging films for monitoring food freshness

Background Synthetic plastics are extremely versatile and convenient materials that can be used to create a diversity of useful products, but their widespread use is causing increasing damage to the planet. As a result, there has been considerable efforts towards the development of more biodegradable and environmentally-friendly materials. Among various alternatives, starch is considered as a good substitute for synthetic polymers due to its abundant supply, low cost, complete biodegradation, high biocompatibility, and good film-forming properties. However, a number of technical challenges need to be overcome to increase the practical of starch-based materials for manner applications. Scope and approach An up-to-date review of starch-based materials is given, with emphasis on methods to improve their properties and widen their application in food packaging. The preparation methods, common additives, characterization techniques, and applications of starch-based biodegradable materials are summarized. Additionally, advanced technological approaches to prepare innovative starch-based biodegradable materials are also introduced to stimulate new areas for future research. Key findings and conclusions Starch-based materials have great potential as biodegradable food packaging materials that will reduce environmental pollution. The functional performance of starch-based biodegradable materials can be extended or improved by adding other biopolymers or additives, as well as by using novel preparation techniques. Nevertheless, the large-scale economic production of high-performance starch-based biodegradable materials is still a challenge and more research is still required in this area.

Starch-based biodegradable packaging materials: A review of their preparation, characterization and diverse applications in the food industry

Background α-Amylase is a key enzyme of starch digestion, playing an important role in deciding glucose releasing amount. Inhibition of the enzyme activity by polyphenols is suggested as a potential approach in controlling starch digestion and regulating postprandial hyperglycaemia. Scope and approach α-Amylase inhibition by polyphenols results from polyphenol-enzyme binding interactions that have been characterized by inhibition kinetics, spectroscopy and thermodynamic analyses. To further elucidate the inhibition mechanism, making the inhibition visible, studies regarding biochemical, biophysical and molecular mechanisms are summarized. Key findings and conclusions Macroscopically, α-amylase inhibition causes retarded digestion of starchy substrates, visible from the production reaction color or fluorescence. Microscopically, detail inhibition kinetics reveals the inhibition types and theoretic interacting sites. X-ray diffraction (XRD) is powerful in extracting the binding modes (detail amino acid residues, polyphenol moieties and interaction forces involved in polyphenol-amylase interactions). Through polyphenol-amylase binding analysis by XRD and NOE correlation of polyphenol atoms by rotating-frame Overhauser enhancement spectroscopy (ROESY)-NMR, the contribution of intramolecular interactions between polyphenol ring-groups to the binding is evaluated. The key phenolic moieties for binding are also obtained by saturation transfer difference (STD)-NMR and/or molecular docking. Besides, by combing fluorescent properties and thermal stability of α-amylase, the enzyme conformational changes may be obtained. Additionally, following delayed starch digestion, α-amylase inhibition is indicated by retarded increase in blood glucose level and colonic fermentation properties of undigested starch. Conclusively, visible characterization helps to understand how a polyphenol develops the inhibitory activity, and to reasonably explore functional factors for alleviation of carbohydrate metabolism disorder.

Inhibition of α-amylase by polyphenolic compounds: Substrate digestion, binding interactions and nutritional intervention

Frying is commonly used by consumers, restaurants, and industries around the globe to cook and process foods. Compared to other food processing methods, frying has several potential advantages, including reduced processing times and the creation of foods with desirable sensory attributes. Frying is often used to prepare starchy foods. After ingestion, the starch and fat in these foods are hydrolyzed by enzymes in the human digestive tract, thereby providing an important source of energy (glucose and fatty acids) for the human body. Conversely, overconsumption of fried starchy foods can promote overweight, obesity, and other chronic diseases. Moreover, frying can generate toxic reaction products that can damage people's health. Consequently, there is interest in developing alternative frying technologies that reduce the levels of nutritionally undesirable components in fried foods, such as vacuum, microwave, air, and radiant frying methods. In this review, we focus on the principles and applications of these innovative frying technologies, and highlight their potential advantages and shortcomings. Further development of these technologies should lead to the creation of healthier fried foods that can help combat the rise in diet-related chronic diseases.

https://www.mdpi.com/2304-8158/10/8/1852/pdf

Effect of New Frying Technology on Starchy Food Quality.

Background Plant-sourced intrinsic dietary fiber (PIDF), mainly composed of nondigestible polysaccharides in a cell wall form, is often existed in plant tissue particles in which the physical structure of the particle size, density and spatial organization of food component as well as the intactness and porosity of cell wall are critical to its physicochemical properties and health functions. However, there is limited information of PIDF compared to isolated and purified DF that is a chemical entity without association with the food context. Scope and approach The health benefit and physical structures of PIDF are emerging as a new research area in the field of DF although there is still limited information in the literature reports. In the current article, available information on the relationship between the physical structure and the physiological function as well as resulted health benefits of PIDF in a whole food context were reviewed in conjunction with food processing. Key findings and conclusions The physical structure of PIDF is a critical factor modulating the intestinal digestion and bioavailability of intracellular nutrients. PIDF can exert its health function through a physical structure-specific microbial fermentation and/or microbiota-independent pathways. A holistic approach to reveal the relationship between the physical structure and health function of PIDF will shed novel insight into the designing of PIDF enriched functional foods.

Plant-sourced intrinsic dietary fiber: Physical structure and health function

A method for preparing a highly branched dextrin product, relating to the field of deep processing, transformation and high value utilization of starch. The method comprises the following main steps: heating, gelatinizing, and declustering starch milk, and then limiting hydrolysis by using α-amylase; using glycogen branching enzyme for treatment; and obtaining a highly branched dextrin product by alcohol precipitation and drying. Starch is declustered in advance by incision by using α-amylase, and the declustering and a biocatalytic transformation technology of glycogen branching enzyme obtained by recombinant heterologous expression of actinomycetales Thermomonospora curvata are combined to synergistically act on the starch for transforming a long amylase substrate into a novel dextrin product of a highly branched structure. The method significantly reduces the preparation time of the highly branched dextrin product, greatly improves the product yield, and features high branch, good solubility, etc.

Ming Miao

Papers

Starch-based biodegradable packaging materials: A review of their preparation, characterization and diverse applications in the food industry

Inhibition of α-amylase by polyphenolic compounds: Substrate digestion, binding interactions and nutritional intervention

Effect of New Frying Technology on Starchy Food Quality.

Plant-sourced intrinsic dietary fiber: Physical structure and health function

Method for preparing highly branched dextrin product