Xuxia Zhou

The effects of light intensity and myoglobin supplementation on lipid oxidation and flavor development in dry-cured grass carp were evaluated. Elevated light intensity and myoglobin supplementation significantly accelerated the conversion of oxymyoglobin to metmyoglobin, creating a potent pro-oxidative environment through photosensitization. This environment further promoted lipid degradation, evidenced by significant increases in thiobarbituric-acid-reactive substances, 4-hydroxyhexenal, and 4-hydroxynonenal, and free fatty acids, while concomitantly depleting total lipids, triglycerides, and phospholipids. Additionally, key volatile aroma compounds, such as hexanal, 3-methylbutanal, and 2-methylbutanal, were significantly enhanced, contributing more to the overall flavor profile than off-flavor compounds like heptanal and 1-octen-3-ol, thereby improving overall flavor quality. Correlation analysis revealed strong links between myoglobin, lipid oxidation, and flavor formation, suggesting that the synergistic effect of myoglobin and light exposure could regulate flavor by promoting lipid oxidation. These findings offer novel theoretical insights and technical guidance for improving flavor quality in the dry-cured aquatic products.

This study aims to address the limitations of solidified goat yogurt (SGY) including poor thermal stability and weak gel properties in formulating ambient‐temperature‐stable products. This study systematically investigated the influence of transglutaminase (TG) crosslinking time on the physicochemical properties, gel structure, rheological behavior, and thermal stability of SGY. The results demonstrated that TG crosslinking time exhibited a biphasic effect, initially enhancing and subsequently diminishing the response. Among the tested treatments, TG‐6 showed the most favorable overall performance, with the highest water‐holding capacity (76.06 ± 0.72%), improved springiness and adhesiveness (0.92 ± 0.02, −21.03 ± 3.54 g·sec), a broader linear viscoelastic region (γc = 0.97 ± 0.08%), and the highest thermal transition temperature ( T _m = 140.12°C). The treatment promoted the formation of a tighter and more uniform gel network by facilitating covalent bonding. This was accompanied by a significant increase in intermolecular hydrogen bonding and a protein secondary structure more conducive to network stability. In contrast, the group of 8‐h treatment exhibited particle aggregation, due to excessive covalent bonds restricting molecular mobility and inducing network stress, with water‐holding capacity decreasing to 62.00 ± 4.63% and T _m dropping to 136.78°C. These findings provided valuable insights for utilizing TG to improve the quality and stability of yogurt.

This study evaluated the effects of deheading and intestinal removal on protein degradation and quality changes in chilled Litopenaeus vannamei. The results showed that shrimp subjected to heads removed (HR) and both heads and intestines removed (HIR) maintained better muscle integrity and sensory characteristics compared with intact (CK) and intestines removed (IR) shrimp. Furthermore, the HR and HIR treatments significantly inhibited the accumulation of total volatile basic nitrogen, trichloroacetic acid-soluble peptides, and bitter free amino acids (including His, Lys, Leu, Val, and Tyr), while maintaining consistently low activities of trypsin, cathepsin B, cathepsins B+L, and cathepsin D in the muscle throughout storage. Additionally, intrinsic fluorescence spectroscopy, SDS-PAGE, and microstructural analyses revealed that HR and HIR treatments significantly delayed muscle protein degradation and effectively preserved the structural integrity of muscle tissue. These findings suggest that quality deterioration of shrimp during chilled storage may be largely associated with the migration of endogenous proteases from the hepatopancreas in the cephalothorax into the muscle tissue.

This study developed a novel equilibrium modified atmosphere packaging (EMAP) membrane. Zeolitic imidazolate framework‐8 (ZIF‐8), a highly porous material with a large specific surface area, was used as a functional filler, aiming to improve CO ₂ /O ₂ selectivity and gas permeability, and was incorporated into a biodegradable polylactic acid (PLA) matrix for preparation. The resulting PLA/PEG@ZIF‐8 membrane, containing 0.75% ZIF‐8, demonstrated exceptional gas selectivity and packaging performance. Specifically, the membrane achieved a significantly enhanced CO ₂ /O ₂ selectivity of 6.35 while maintaining favorable gas permeability. Furthermore, the water vapor transmission rate was effectively reduced. The membranes demonstrated substantial improvements in both elongation at break and tensile strength, indicating enhanced mechanical properties. In addition, the membrane retained its hydrophobicity and desirable swellability, while showing remarkedly improved UV‐blocking properties. Negligible zinc ion migration was observed, ensuring safety, as confirmed by cell viability exceeding 97% in cytotoxicity assays. These characteristics contribute to maintaining an optimal internal gas composition within the package, thereby effectively inhibiting microbial growth and nutrient loss, thus extending the shelf life of cherry tomatoes. Overall, the PLA/PEG@ZIF‐8 EMAP membrane demonstrates significant potential for preserving high‐respiration fresh fruits, highlighting its promising application in food preservation technology. Practical Applications: The PLA/PEG@ZIF‐8 membrane was fabricated with superior CO ₂ /O ₂ selectivity. The membrane exhibited enhanced gas permeability and packaging performance. The shelf life of cherry tomatoes was remarkably extended by packaging with the membrane.

Pro-oxidative factors compromise surimi gel quality by inducing protein denaturation and aggregation. This study elucidated the interactions between malondialdehyde (MDA) and hemin with surimi actomyosin through multispectral analysis and molecular dynamics (MD) simulations. The results suggested that MDA and hemin induced actomyosin oxidation by altering protein conformation, surface hydrophobicity, and the microenvironment of aromatic residues, especially under low-pH/high-temperature conditions. The MD results confirmed that MDA weakly interacted with myosin owing to its flexible backbone and limited hydrophobicity (ΔE = +0.24 kcal/mol), whereas hemin forms stable interactions (ΔE = −33.64 kcal/mol), likely due to its central iron atom, rigid porphyrin ring, and polar groups. Under co-exposure, hemin facilitated the relocation of MDA into deeper binding pockets, forming a synergistic network driven by hydrogen bonding, van der Waals forces, and hydrophobic interactions (ΔE = +0.05 kcal/mol for MDA; −28.71 kcal/mol for hemin). These findings provide molecular-level insights into surimi quality deterioration and support strategies to mitigate protein oxidation during processing. The alternative text for this image may have been generated using AI.

Microbial starters determine the quality of fermented shrimp products. Three different rice wine lees starters (HSF, CZ, and AQ) were employed to ferment pacific white shrimp under controlled conditions. The microbial community analysis indicated that HSF and CZ starters were dominated by Firmicutes or Ascomycota, with Pichia and Limosilactobacillus as the characteristic genera, whereas AQ was dominated by Mucoromycota, primarily Rhizopus. Fermentation with different rice wine lees significantly increased color values (L*, a*, and b*) and introduced more desirable volatile compounds. Total volatile contents varied markedly across fermented shrimps, ranked as HSF shrimp (236.41 µg/g) > CZ shrimp (178.60 µg/g) > AQ shrimp (87.27 µg/g). Correlation network model analysis further revealed that Firmicutes and Ascomycota exhibited significantly positive correlations with higher alcohols and esters, like 2-phenylethyl acetate and 2-phenylethanol. This study clarify the microbial mechanisms underlying flavor formation and provide a theoretical basis for valued-added fermented shrimps.

Both plasma-activated water (PAW) and pulsed electric field (PEF) are effective in killing microorganisms and preserving food. However, how they work together is not fully known. This study examined the antimicrobial efficacy and underlying mechanisms of PAW-PEF co-treatment against Escherichia coli (E. coli) in suspension, and also within a blueberry model. The results revealed that the bactericidal effectiveness of the PAW-PEF co-treatment significantly surpassed that of each treatment applied separately. Specifically, in suspension, this co-treatment achieved an enhanced reduction of E. coli by 1.11 log CFU/mL and 2.42 log CFU/mL compared to PEF and PAW treatments alone under optimal conditions. Additionally, in the blueberry model, the co-treatment approach reduced E. coli levels by 1.54 log CFU/g. An investigation into bactericidal mechanisms demonstrated that PEF treatment enhances the transport of reactive oxygen/nitrogen species (ROS/RNS), such as hydrogen peroxide (H2O2) and nitrite (NO2-), from PAW into bacteria, thereby increasing intracellular oxidative stress. This heightened oxidative stress inflicts irreversible oxidative damage on the cell membrane, leading to morphological rupture, increased permeability, and severe lipid peroxidation. Furthermore, the elevated oxidative stress undermines the bacterial antioxidant defense system, disrupting the reduced and oxidized glutathione (GSH/GSSG) balance and impairing intracellular antioxidant enzymes. The collapse of the antioxidant system, combined with cellular membrane damage, ultimately leads to bacterial inactivation. This study enhances our understanding of the antimicrobial mechanisms of PAW-PEF co-treatment and offers critical insights for developing preservation technologies for fruits and vegetables.