The role of the food matrix in peptide bioavailability: a review of interactions and their impact on absorption.

Bioavailability of dietary polyphenols and plant bioactives in functional foods: insights and limitations from in vitro digestion models

This review provides a comprehensive evaluation of how bioactive compounds within plant- and animal-derived food matrices interact with human physiology and metabolic pathways, with a particular focus on secondary metabolites synthesized or transformed via microbial pathways. The manuscript covers a diverse range of lipophilic and hydrophilic bioactive molecules, critically analysing these components from biological and technological perspectives. From a processing perspective, the mechanisms by which fermentation enhances antioxidant capacity by converting complex molecular structures into highly active aglycone forms are detailed. Concurrently, from an engineering perspective, the efficiency of nanoliposomes, solid lipid nanoparticles (SLNP), and biopolymeric carrier systems is assessed. Rather than claiming that encapsulation technologies can entirely overcome bioavailability limitations, this review critically assesses their potential to improve the stability, bioaccessibility and targeted release of sensitive components during gastrointestinal transit. Ultimately, by bridging microbial biotransformation with advanced delivery systems, this study offers a unified framework for optimizing the bioaccessibility of complex dietary compounds under simulated gastrointestinal conditions.

The journey of bioactive peptides in vivo: cutting-edge advances in absorption, transport, and bioavailability.

Oral Delivery Systems for Food‐Derived Bioactive Peptides: Enhancing Stability, Bioavailability, and Health Benefits

Food‐derived bioactive peptides (FBPs) represent a promising class of nutraceuticals for the prevention and management of chronic diseases due to their diverse bioactivities and high biocompatibility; however, their therapeutic potential is severely limited by low oral bioavailability resulting from instability during processing, sensory drawbacks such as bitterness, and extensive gastrointestinal degradation. This review systematically outlines the major bottlenecks hindering the oral delivery of FBPs, including sensitivity to environmental factors (temperature, pH, metal ions) and physiological barriers (enzymatic hydrolysis, mucus layer, and epithelial transport). To overcome these challenges, advanced delivery systems, such as nanoparticles (NPs), nanoemulsions (NEs), liposomes, hydrogels, and composite carriers, have been designed. These engineered systems have demonstrated enhanced bioactivity and targeted delivery in preclinical models of neuroprotection, anti‐inflammatory therapy, metabolic regulation, and cancer treatment, often outperforming free peptides in terms of stability and intestinal absorption. However, establishing quantitative correlations between formulation parameters and in vivo peptide bioavailability remains a critical bottleneck. Future research should focus on rationally designed stimuli‐responsive platforms grounded in intestinal physiology, supported by standardized frameworks for scalable manufacturing and safety evaluation. This work provides a comprehensive framework for advancing FBPs delivery platforms toward functional food and chronic disease management applications.

Bioactive Compounds in Functional Meals: Bioavailability Challenges, Food Technology Approaches, and Health Perspectives—A Narrative Review

Functional meals are emerging, encompassing complete meal systems designed to deliver physiological benefits through food synergy, interactions with the food matrix, and optimized release of bioactive compounds. This narrative review examines the role of bioactive compounds in functional meals, with particular emphasis on bioavailability, food matrix effects, technological approaches, and health implications. Bioactive compounds can contribute to cardiometabolic, anti-inflammatory, gastrointestinal, and neuroprotective effects. However, their biological efficacy depends not only on their concentration in foods but also on their release from the food matrix, stability during processing and digestion, intestinal absorption, microbiota-mediated transformation, and post-absorptive metabolism. Therefore, functional meals represent complex systems in which food structure, culinary preparation, processing intensity, co-ingested nutrients, and host-related factors determine the final physiological response. Emerging technologies, including microencapsulation and nanoencapsulation, offer promising strategies to improve the stability, bioaccessibility, targeted release, and sensory acceptability of bioactives. Future research should prioritize well-designed human studies, standardized methodologies, clinically relevant outcomes, personalized nutritional approaches, and sustainable food system integration to support the development of effective, evidence-based functional meal strategies.

Chemical Fate of Polyphenols in Food Systems: Processing-Induced Modifications, Matrix Effects, and Implications for Bioaccessibility

Polyphenols are bioactive compounds abundant in plant-based foods, contributing to antioxidant, anti-inflammatory, and antimicrobial effects. Their stability, bioaccessibility, and functional potential are influenced by chemical structure, food matrix composition, and processing. Thermal, non-thermal, and fermentation-based treatments can either degrade sensitive polyphenols or enhance extractability and biological activity, depending on the matrix. Interactions with proteins, polysaccharides, and lipids modulate release during digestion, with bound or complexed forms often exhibiting delayed bioaccessibility and colonic microbial transformation. Accurate characterization relies on analytical methods ranging from spectrophotometry to HPLC–MS/MS, NMR, and metabolomics, yet methodological limitations can obscure functional content. This review integrates current knowledge on polyphenol chemistry, processing effects, matrix interactions, bioaccessibility, and analytical approaches, highlighting practical implications for functional food development and research gaps for future studies.

Plant Protein-Derived Bioactive Peptides: From Mechanistic Promise to Health-Promoting Functional Foods

Plant protein-derived bioactive peptides have attracted increasing interest as potential ingredients for health-promoting functional foods because of their reported cardiometabolic, antioxidant, anti-inflammatory, immunomodulatory, antimicrobial, gastrointestinal, and satiety-related activities. However, the field remains dominated by peptide discovery, in silico prediction, enzyme-inhibition assays, simulated digestion, and preclinical models, whereas successful translation into clinically supported and technologically viable food products is still limited. This review critically examines the gap between mechanistic promise and functional food implementation. It integrates evidence on plant protein sources, peptide-generation strategies, structure–activity relationships, gastrointestinal stability, intestinal transport, local gut activity, food-matrix interactions, processing effects, encapsulation, sensory constraints, human efficacy, regulatory substantiation, commercial feasibility, and consumer acceptance. Particular attention is given to the limited predictive value of isolated in vitro activity when peptides are exposed to digestion, epithelial barriers, complex food matrices, realistic processing conditions, and achievable dietary doses. The review also highlights that systemic absorption is not the only relevant pathway, as selected peptides may act locally within the gastrointestinal tract. Overall, the evidence indicates that peptide discovery should not be treated as the principal endpoint of research. Future progress will require translation-oriented development in which bioactivity, digestion stability, matrix compatibility, sensory quality, manufacturing reproducibility, realistic intake, human evidence, and regulatory credibility are evaluated as interdependent criteria. The most promising plant-derived peptides will therefore be those that retain sufficient activity and acceptability under real conditions of food production and consumption.