Editorial: In vitro digestion in the study of food

In vitro digestion models are widely used to study how foods and pharmaceuticals behave along the gastrointestinal tract. Although human nutrition studies remain the gold standard, simulated digestion is faster, cheaper, less labor-intensive and free of ethical constraints, enabling parallel screening and highly controlled, reproducible mechanistic work with easy sampling at specific sites. The international INFOGEST network has played a significant role in this area, particularly in standardizing and validating a static in vitro digestion protocols and correlating these findings with in vivo data (1-3). The standardized in vitro digestion protocols are essential to assess the gastrointestinal fate of foods under controlled conditions, focusing on matrix-driven release, stability, and bioaccessibility of nutrients and bioactives. Their applications now span macronutrient digestibility, post-digestive behavior of phytochemicals (e.g., polyphenols and carotenoids), and the production of bioaccessible. By reducing methodological variability, harmonized protocols (INFOGEST-like) strengthen crossstudy comparability while remaining adaptable to different food matrices and research aims (4,5). Moreover, the digested foods can be applied for downstream mechanistic assays such as epithelial transport models (6).Yıkmış et al. applied INFOGEST in vitro gastrointestinal digestion (followed by dialysis) to test whether processing improved bioactive delivery in dill (Anethum graveolens) juice beyond simple retention. Comparing control, pasteurized and thermosonicated juices, they quantified post-digestion bioaccessibility of phenolics, β-carotene, chlorophyll and FRAP activity, and related these outcomes to GC-MS aroma profiles. Thermosonication yielded the highest post-digestion levels of key bioactives and was associated with aroma-function correlations, while also preserving volatile stability better than conventional heating. Overall, the authors concluded that thermosonication enhanced antioxidant quality and post-digestion bioaccessibility of dill juice bioactives. Bietto et al. illustrated a complementary application of in vitro digestion in early-life nutrition research by using it to generate infant formula digesta. The digesta was then used to study the crossing of an infant-like intestinal barrier in a controlled cell model. The authors developed an in vitro temporary infant-like gut barrier model treating Caco-2/HT29-MTX monolayers with sodium glycodeoxycholate (GDC). The infant milk was digested by INFOGEST protocol, the enzyme action was stopped adding the inhibitor enzymes and the digesta was add to the apical compartment of the Caco-2/HT29-MTX monolayers with and without the GDC treatment for 2 h recording TEER values. GDC connected reactors that mimic the stomach, small intestine, ascending colon, transverse colon, and 62 descending colon. In this procedure, they have referred to the INFOGEST protocol for pre-conditioning 63 the yogurt dose with a simulated salivary solution and a pepsin-containing gastric step before 64 introducing it into the xGIbiomics® system. 65Another aspect of the digestion is the utilization of the enzymatic digestion to generate potentially 66 bioaccessible fractions that can then be evaluated for biological relevance. Yang et al. used enzymatic 67 digestion to produce quinoa protein hydrolysates and assess how protease choice shaped antioxidant 68 potential. They compared four enzymes, including the digestive proteases pepsin and trypsin alongside 69 industrial proteases, linking hydrolysis features (degree of hydrolysis and low-MW peptides) to 70 antioxidant assays and HepG2 cytoprotection, and positioning enzymatic digestion as an upstream step 71 for generating bioactive pools relevant to health food products applications. 72In addition to the experimental papers that modelled gastrointestinal fate through simulated digestion 73 and colonic fermentation platforms, Semchyshyn reviewed dietary glycation products as a 74 paradigmatic case in which limited small-intestinal absorption and extensive microbial processing in 75 the colon jointly shape physiological exposure and downstream health effects. The author emphasized 76 that a substantial fraction of ingested glycotoxins may escape small-intestinal uptake, thereby 77 interacting with the gut microbiota and potentially influencing both microbial ecology and systemic 78 outcomes. While high exposure has been associated with inflammation and oxidative/carbonyl stress, 79 the review also discussed the possibility of adaptive effects at lower levels and highlighted major 80 knowledge gaps in defining "physiological" exposure ranges and host-microbe contributions to 81 glycotoxin handling. 82In summary, the papers gathered in this Research Topic provided a diverse and timely set of examples 83showing how simulated digestion, when coupled with food processing, intestinal cell models, and 84