With extremely low odor thresholds and potent flavor activity, sulfur-containing aroma compounds (SACs) constitute the molecular cornerstone of characteristic flavors in meat, coffee, and fermented foods. Research has advanced from early component identification to the elucidation of structure–activity relationships, olfactory receptor recognition mechanisms, and food-flavor improvement. This review first summarizes the detection and quantification methods for SACs, their distribution in foods, key odor contributions, and major formation pathways. It then highlights progress in understanding molecular structural parameters, olfactory receptor recognition, and computational simulations that decode flavor perception mechanisms. From a translational perspective, we further discuss flavor retention in real food matrices, off-flavor regulation, cross-modal perceptual enhancement, and functional applications. Current challenges include food matrix complexity, high compound reactivity, and nonlinear olfactory combinatorial coding. Future directions involve constructing a multiscale predictive framework integrating neuroscience, developing explainable artificial intelligence to decode olfactory coding, and advancing closed-loop green biomanufacturing for the precise design and sustainable production of SACs.

Probiotics exert profound health benefits via the modulation of the intestinal microbiota. However, the efficacy of orally administered probiotics is severely constrained by a cascade of physiological barriers, including gastric acid inactivation, suboptimal intestinal release, and inadequate mucosal colonization. In response to these challenges, hydrogel-based delivery platforms have garnered considerable interest as versatile carriers capable of providing protective encapsulation, enabling spatiotemporally controlled release, and augmenting intestinal retention. This narrative review presents recent progress in the design and application of hydrogel-based oral delivery systems tailored for targeted probiotic release and effective colonization. First, the key gastrointestinal obstacles to successful probiotic delivery are delineated. Hydrogel design parameters are then critically appraised, with particular emphasis on material selection and network design. The underlying release mechanisms are subsequently examined. These encompass pH-responsive, enzyme-triggered, and inflammation-responsive modalities. Emerging colonization-enhancing strategies are discussed in detail. These include mucoadhesive hydrogel architectures and the nascent paradigm of “living hydrogels” functioning as dynamic bioreactors. The translational potential of these systems for health management is illustrated through applications in inflammatory bowel disease, colorectal cancer, and gut–brain axis modulation. Finally, key challenges in manufacturing, viability, and translational feasibility are evaluated. These include regulatory, safety, and encapsulation-related constraints. To address these, multi-responsive platforms, machine learning-assisted design, and synbiotic hydrogels are proposed. These hydrogels synergize with probiotics to target dysbiosis and repair mucosal damage for improved gastrointestinal health management.

This work evaluated how ferulic acid (FA) impacted the conformational properties of whey protein isolate (WPI) and altered the environmental tolerance of oleogel/water (Og/W) emulsions formulated with Ganoderma lucidum spore oil (GLSO). Molecular dynamics simulation analyses revealed that FA interacted with α-lactalbumin via hydrogen bonding and hydrophobic interactions, whereas it bound into the hydrophobic cavity of β-lactoglobulin through a “lock-and-key” mode driven primarily by hydrophobic forces. Fourier transform infrared spectroscopy analysis verified that such non-covalent forces triggered the dissociation and structural extension of WPI, which was manifested as a significant loss of α-helix and β-sheet architectures along with a corresponding rise in random coils. FA addition increased the positive charge, mean droplet size, interfacial contact angle and antioxidant stability of WPI-FA nanoparticles when the WPI-to-FA ratio exceeded 1:2 (i.e., WPI was in excess relative to FA). The GLSO-based Og/W emulsions exhibited a weak gel structure with predominantly elastic characteristics. Furthermore, WPI-FA nanoparticles fabricated at a 2:1 ratio minimized emulsion droplet size and imparted optimal stability to the Og/W emulsions, demonstrating superior freeze–thaw and salt resistance, alongside suppressed GLSO flavor release. This work provides critical insights into tailoring protein-polyphenol interactions to stabilize GLSO-based Og/W emulsion delivery systems for food applications.