Foods最新文献

Lycopene is a naturally potent lipophilic antioxidant, which limits its bioavailability for absorption during intestinal digestion. Therefore, this study utilized a self-emulsifying delivery system (SEDS) to enhance the solubility and bioavailability of lycopene and investigated the effects of nonionic surfactant mixtures at varying hydrophilic-lipophilic balance (HLB) values and surfactant-to-oil ratios (SORs) on SEDS using oleic acid (OA), medium-chain triglycerides (MCTs), and sunflower oil (SO) as oil matrices. The resulting water-in-oil-in-water emulsions exhibited droplet sizes (181.70 to 572.27 nm), polydispersity indices (0.29 to 0.86), and ζ-potentials (-22.90 to -53.70 mV), with stability varying according to the type of oil and formulation parameters. Antioxidant activities of SO-based SEDS were higher compared to MCT-based and OA-based ones due to lycopene loading increase. In vitro simulated intestinal digestion revealed differences in lipolysis kinetics, with MCT-based lycopene-loaded SEDS exhibiting enhanced cumulative release and bioaccessibility in the duodenal (1.1-2.1 mEq/g) and jejunal (1.6-2.2 mEq/g) segments. This study revealed a comprehensive strategy encompassing lycopene extracts, SEDS preparation, quality indices, lipolysis dynamics, and proximal intestine solubilization amounts that successfully enhanced lycopene bioavailability. Optimized MCT-based lycopene-loaded SEDS with high HLB (10.72) and SOR (1.00) enhanced hydrophobic bioactive delivery efficiency, offering a novel low-energy strategy for developing functional supplements.

Faced with the transformation of food and the rapid pace of life among university students, consumption behaviors for food products such as Andean grains have become significant topics. To better understand this issue, this study aimed to analyze the factors that influence the purchase intention of Andean grains in university students, based on the theory of planned behavior, self-identity, moral obligation, and willingness to pay more. The study recruited 900 university students, and the results report that moral obligation is the strongest predictor (β = 0.295), followed by self-identity (β = 0.293). These findings confirm the need to explore new opportunities for transforming and innovating Andean grains.

Volatile organic compounds (VOCs) are key aroma determinants in pork, and gas chromatography-ion mobility spectrometry (GC-IMS) is an effective technique for their detection. However, the detection conditions for pork using GC-IMS have yet to be standardized. This study employed GC-IMS to investigate the effects of incubation (temperature/duration) and medium (water and different concentrations of NaCl) environments on VOCs in pork. Statistical analyses including t-tests, PLS-DA, and OPLS-DA were employed to assess VOC differences. The results showed that: (1) VOC diversity and intensity increased with incubation temperature and time, with optimal signals obtained at 100 °C for 20 min. (2) The sample medium significantly influenced aroma release. When the medium contained 10% NaCl, the relative content of aldehydes increased, showing that these compounds were optimally released. (3) Under the optimized conditions, 15 key differential VOCs were identified from different muscle tissues, including 10 aldehydes, 2 esters, 1 ketone, 1 alcohol and 1 ether. This work establishes practical GC-IMS parameters for pork VOC analysis and provides a reliable reference for flavor-related studies.

Sour cream is a functional dairy product with a unique taste and high nutritional value. In this study, Lactococcus lactis grx602, a strain capable of degrading milk fat, was used to produce sour cream (a fermented dairy-based emulsion, designated as Lg-sour cream). The preparation process was optimized and the quality stability during storage was evaluated. The optimal preparation parameters were identified as double-pass homogenization (15.0 MPa, 70 °C), a 1% inoculation level, and fermentation at 37 °C. During storage, Lg-sour cream exhibited acceptable fluctuations in fermentation characteristics (viable cell count, pH and acidity), continuous decreases in textural properties (hardness, adhesiveness, cohesiveness, and elasticity), progressive declines in rheological properties (water-holding capacity, apparent viscosity and viscosity), and positive variations in free fatty acid composition (types and contents of fatty acids with different chain lengths). This study provides an in-depth exploration of the nutritional value, storage stability, and processing of Lg-sour cream fermented with L. lactis grx602, aiming to develop a novel sour cream with potential health benefits using L. lactis grx602 as the starter culture.

This study investigated the potential of Fraction I (FI, <1 kDa), a peptide fraction derived from whey protein hydrolysates (WPH) exhibiting strong in vitro scavenging activity against DPPH, superoxide, and hydroxyl radicals, to mitigate quality deterioration in ground pork subjected to up to seven freeze-thaw (F-T) cycles. Ground pork samples were supplemented with FI at three concentrations (5%, 10%, and 15%) and analyzed for oxidative and physicochemical changes. Successive F-T cycles markedly promoted lipid oxidation, as indicated by increased peroxide value and thiobarbituric acid reactive substances (TBARS), and overall quality deterioration, evidenced by a rise in acid value and pH along with a decrease in G″. Incorporation of 10% FI effectively inhibited these oxidative reactions and improved the water-holding capacity of ground pork. These results demonstrate that among the tested concentrations, FI at 10% most effectively enhances oxidative stability and maintains water distribution, thereby preserving the quality of ground pork during multiple F-T cycles.

This study aimed to investigate the influence of lipid oxidation intensity on histamine accumulation in fermented sausages and to identify specific lipid oxidation products potentially responsible for promoting histamine formation. Pork backfat was subjected to controlled oxidation at different temperatures to obtain varying degrees of oxidation and subsequently used in fermented sausage production. Histamine content was determined, and treatment groups exhibiting significant differences (50 °C, 60 °C, and 70 °C) were selected for further non-targeted metabolomic analysis. Multivariate statistical approaches, including PCA and OPLS-DA, were employed to screen and identify differential lipid oxidation products. The results revealed a significant positive correlation between the extent of lipid oxidation and histamine content (p < 0.05). Within the selected temperature range, the mean histamine contents were 22.97, 19.05, and 17.45 mg/kg for the 70 °C, 60 °C, and 50 °C treatments, respectively. A total of 33 lipid oxidation products were identified during ripening, predominantly aldehydes, ketones, alcohols, esters, acids, and alkanes. Pearson correlation analysis showed that four compounds-decanal, nonanal, hexanal, and 1-octen-3-ol-were strongly and positively correlated with histamine content (p < 0.01). These compounds were highlighted as key lipid-derived contributors potentially associated with elevated histamine levels. This study provides initial evidence that specific lipid oxidation products are closely linked to histamine accumulation in a real fermented sausage matrix. The findings offer a theoretical basis for reducing biogenic amine formation by controlling lipid oxidation during processing, which could have important practical implications for improving the safety of fermented meat products.

Per- and poly-fluoroalkyl substances (PFAS) are synthetic compounds known for their environmental persistence, bioaccumulation, and adverse human risks. This study presents Singapore's first Total Diet Study assessing the occurrence and dietary exposure of four PFAS, with 503 pooled samples analysed across 23 categories of commonly consumed food prepared using representative cooking methods. The majority (75%) of the food categories had non-detectable levels. Fish and seafood accounted for 89.7% of detections, with frequencies in decreasing order of PFOS > PFOA > PFNA > PFHxS, and an overall mean concentration of 0.67 µg/kg. As 93% of results are left-censored, dietary exposure assessment using a lower bound approach (LB) identified clams and crabs as having a higher estimated exposure risk for consumers, exceeding the EFSA's Health-Based Guidance Value of 0.63 ng/kg bw/day by factors of 4.8 and 1.9, respectively. PFAS LB dietary exposure for the general population was estimated at 3.1 × 10^-3 ng/kg bw/day (average) and 1.7 × 10^-1 ng/kg bw/day (95th percentile), indicating a low risk to the population. However, the limit of quantification of 0.1 μg/kg requires improvement to reduce left-censored data and improve dietary estimates. Further research including a broader range of PFAS compounds is recommended for high-risk food categories to increase the accuracy of exposure assessments.

Pasuchaca (Geranium dielsianum Knuth), a traditional Peruvian medicinal plant from the Geraniaceae family used for diabetes management, was investigated for its antiglycative properties. This study aimed to screen, isolate, and identify the active antiglycative compounds from its aerial parts. By coupling a methylglyoxal (MGO)-HPLC screening assay with high-speed counter-current chromatography (HSCCC), seven dihydroflavonol derivatives were separated and identified from the 80% methanol extract. The compounds were identified as 2,3-dihydromyricetin 3-O-α-rhamnopyranoside (1), (+)-taxifolin 3-O-β-D-xylopyranoside (2), astilbin (6), isoastilbin (8), 3″-acetyl astilbin (9), and 2″-acetyl astilbin (11). Astilbin was identified as the major constituent, with remarkably high contents of 252.41 mg/g in the 80% methanol extract and 541.04 mg/g in the partitioned upper layer fraction. Astilbin demonstrated potent antiglycation activity across all stages of protein glycation (early, middle, late, and whole stages), significantly surpassing the positive control aminoguanidine. Furthermore, the formation of MGO-astilbin adducts was confirmed by LC-ESI-MS, validating its role as an effective MGO scavenger. This report is the first to isolate these phytochemicals from Pasuchaca. The findings establish astilbin as the key antiglycative component of Pasuchaca, substantiating its traditional use and highlighting its potential as a source of functional food ingredients or natural therapeutics for mitigating glycative stress.

This study evaluated the antagonistic activity of the cell-free supernatant of Lacticaseibacillus rhamnosus ATCC 9595 (Lcr-CFS) against Listeria monocytogenes, a major foodborne pathogen, that represents a challenge to food safety, due to its remarkable tolerance to environmental stresses and strong biofilm-forming ability. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of Lcr-CFS against L. monocytogenes were defined as 31.25 and 62.5 mg/mL, respectively. Time-kill assays revealed dose- and time-dependent bactericidal effects. At sub-MICs, Lcr-CFS significantly reduced L. monocytogenes biofilm formation, disrupted preformed biofilms and decreased cell viability (80.3-96.7%), effects that were confirmed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and fluorescence microscopy. Transmission electron microscopy showed L. monocytogenes cell wall damage, cytoplasmic leakage, and morphological alterations consistent with bactericidal effects. Additionally, exposure to 1x and 2x MIC of Lcr-CFS induced reactive oxygen species (ROS) accumulation, indicating oxidative stress as part of the mechanism by which Lcr-CFS exerts its antimicrobial activity. Gene expression analysis revealed upregulation of stress and virulence-associated genes (sigB, prfA, degU, flaA, motA, hlyA, pclA, and actA) upon exposure to 0.5x MIC suggesting a complex cross-talk network between adaptive mechanisms and environmental stresses. Although L. monocytogenes initiates a stress response, it appears unable to counteract the damage induced by Lcr-CFS, resulting in cell death. These findings highlight the antimicrobial and anti-biofilm properties of Lcr-CFS against L. monocytogenes. Given its in vitro efficacy, Lcr-CFS emerges as a promising biocontrol agent to improve food safety by mitigating the persistence of L. monocytogenes in food processing settings.

Daqu, a representative solid-state fermentation product, produces saccharifying enzymes to degrade sorghum starch into fermentable sugars for ethanol synthesis. Spatial heterogeneity in Daqu drives community assembly. However, its regulatory role in enzyme-driven saccharification remains unclear. By integrating metagenomics and PacBio full-length sequencing, this study investigated how microenvironmental gradients across distinct Daqu layers (QP (surface layer), HQ (middle layer), QX (center layer)) shape saccharifying microbiota and activity. Saccharifying activity exhibited a declining surface-to-center gradient (e.g., QP: 870.9 ± 21.2 U/mL > HQ: 631.2 ± 16.4 U/mL > QX: 296.5 ± 16.1 U/mL on day 30, p < 0.05), paralleled by divergence in microenvironments. Metagenomics identified α-amylase and α-glucosidase as key saccharifying enzymes, primarily encoded by fungi; their abundance was inhibited by heat and humidity, yet promoted by acidity. Enzymatic validation confirmed higher saccharifying activity in QP and HQ core microbes (e.g., Lichtheimia ramosa: 43.16 ± 1.97 U/mL) than in QX (e.g., Paecilomyces variotii: 14.27 ± 1.25 U/mL). Network analysis revealed Lactobacillaceae are closely linked with saccharifying communities. This study establishes microenvironmental gradients as critical regulators of spatial saccharification in Daqu, informing strategies to optimize microbial consortia for baijiu production.