Abstract:To investigate the effects of 1,3-dioleoyl-2-palmitoyl-glycerol (OPO) on the gut health of weanling mice, we fed weanling mice for four weeks, classified them into three groups: the control group (CON group), the low-dose OPO (LOPO) group, and the high-dose OPO (HOPO) group, and compared the groups. Various indicators were analyzed, such as serum inflammation levels, intestinal tissue morphology, gene expression of tight junction proteins, intestinal permeability markers, gut microbiota diversity, and changes in short-chain fatty acids (SCFAs). The results showed that, compared with the CON group, serum levels of TNF-α and IL-1β decreased by 9.05% (P<0.01) and 9.71% (P<0.05), respectively, in the LOPO group and 10.71% (P<0.001) and 7.84%, respectively, in the HOPO group. The relative mRNA expression of claudin-1 increased by 31.37% (P<0.05) in the LOPO group when compared with the CON group, whereas the value increased by 38.24% (P<0.001) in the HOPO group. Additionally, serum LPS levels in the LOPO and HOPO groups decreased by 8.43% and 8.66% (P<0.05), respectively, compared with the CON group. Furthermore, dietary OPO regulated the gut microbiota composition, increasing the relative abundance of Akkermansia, Dubosiella, and Bifidobacterium and decreasing the relative abundance of Desulfovibrio. SCFA results indicated that, compared with the CON group, the contents of acetic acid, propionic acid, butyric acid, and valeric acid increased by 162.32%, 72.7%, 216.24%, and 25.2%, respectively, in the LOPO group and by 160.68%, 74.58%, 163.85%, and 23.03%, respectively, in the HOPO group (P<0.001). In conclusion, dietary OPO may enhance intestinal barrier function and inhibit systemic inflammatory responses in weanling mice by modulating gut microbiota and related SCFA metabolism. These findings provide a theoretical basis for targeted regulation of gut microbiota by OPO.

Abstract:To investigate the therapeutic effects of ellagic acid (EA) on allergic rhinitis (AR) and its potential mechanisms of metabolic regulation, different doses of EA (4, 8, and 16 mg.kg-1) were administered to ovalbumen-induced AR rats. Pathological changes in nasal mucosa and lung tissue were observed, levels of IgE, histamine, IL-4, and IL-6 in serum were measured, and metabolite changes along with their correlations with allergic inflammation markers were analyzed using untargeted metabolomics. The results showed that EA interventions reduced the number of mast cells in the nasal mucosa and lung tissue and decreased the levels of IgE, histamine, IL-4, and IL-6 in the serum, with the high-dose group showing the most significant improvements (reductions of 26.40%, 23.79%, 21.65%, and 35.00% in the abovementioned indicators, respectively). Untargeted metabolomics identified 43 differential metabolites, among which 22 were significantly restored after intervention (P<0.05), including 19 metabolites positively correlated and 3 negatively correlated with allergic inflammation markers. Enrichment analysis revealed that the restored metabolites were significantly enriched in three pathways: arachidonic acid metabolism, primary bile acid biosynthesis, and porphyrin metabolism. In conclusion, EA alleviates AR by improving pathological tissue conditions, reducing allergic inflammation markers, and regulating key metabolic pathways. These findings provide new insights into the application of EA and related polyphenols in the development of anti-allergic functional foods.

Abstract:The aim of this study was to investigate the protective effects of Moringa oleifera leaf polysaccharide (MLP) on rhabdomyolysis-induced acute kidney injury (RM-AKI) and the potential mechanisms of such effects. A mouse RM-AKI model and a ferrous myoglobin-induced injury model were established in renal tubular epithelial cells (HK-2). Biochemical kits were used to measure the levels of creatinine (Cr), blood urea nitrogen (BUN), and creatine kinase (CK) in mouse serum, as well as cytokines (IL-1β, IL-6, and TNF-α) in kidney tissue. Furthermore, hematoxylin and eosin staining and TUNEL staining were used to evaluate pathological changes and apoptosis in kidney tissue. Western blotting was performed to evaluate the expression of key proteins in both kidney tissue and HK-2 cells. The results revealed that, compared with the model group, the levels of Cr, BUN, CK, IL-1β, IL-6, and TNF-α in the high-dose MLP-treated mice decreased by 67.87%, 43.03%, 21.39%, 31.05%, 54.20%, and 51.66%, respectively (P<0.001). In addition, HK-2 apoptosis was significantly inhibited, and oxidative stress levels notably decreased in ferrous myoglobin-induced HK-2 cells. A significant downregulation in the expression of TLR4, P-p65/p65, and cleaved caspase-3, both in vivo and in vitro, was observed after MLP treatment. These results indicate that MLP has a significant protective effect on RM-AKI, which provide a scientific basis for the clinical treatment of patients with RM-AKI.

Abstract:Based on the intestinal damage induced by deoxynivalenol (DON) in KM mice, to investigate the protective effect of apigenin (API) and reveal its potential mechanism, healthy male KM mice were randomly divided into a control group, a DON group, a low-dose API group, a high-dose API group, a low-dose API intervention group (low-dose API+DON), and a high-dose API intervention group (high-dose API+DON). The protective effects of API against DON-induced intestinal injury in KM mice were comprehensively assessed through multiple approaches: monitoring of body weight, pathological staining of colonic tissue with hematoxylin-eosin, TUNEL apoptosis staining, western blotting analysis of apoptosis-related protein expression, and measurement of serum lactate dehydrogenase (LDH), total superoxide dismutase (SOD), and malondialdehyde (MDA) levels. The results showed that, compared with the blank group, the DON group exhibited significantly decreased body weight after peaking on day 19, and high-dose API intervention successfully mitigated the trend of weight loss. Pathological examination revealed that colonic tissue damage improved after high-dose API intervention, and the pathological score of damage was reduced by 1.3 when compared with that of the DON group. TUNEL staining showed that API interventions significantly reduced the count of apoptotic cells. Western blot analysis further confirmed that API intervention down regulated the expression of apoptotic proteins Bax, P53, caspase-12, and caspase-9 and decreased the expression of Bcl-2. Serological assays revealed that, compared with the DON group, high-dose API intervention reduced LDH level by 7.53% (P<0.05), increased SOD activity by 46.82% (P<0.05), and reduced MDA level by 12.25% (P<0.05). These results indicate that API has a significant protective effect on DON-induced intestinal injury in KM mice, and the mechanism may be related to the synergistic effects of multiple pathways, including the inhibition of DON-induced apoptosis in colonic tissue as well as improvement of serum LDH and SOD activities in the mice. This study provides strong theoretical support for the potential application of API as a functional food ingredient in the prevention and treatment of DON-related intestinal injury.

Abstract:To investigate the effects of sea-buckthorn oil content and manuka honey addition on the functional activities of sea-buckthorn puree, the in vitro antioxidant, antibacterial, and immunomodulatory effects of Chunjian sea-buckthorn puree with different oil contents and with or without manuka honey were determined. The antioxidant experiment was conducted using DPPH and ABTS methods. In the antibacterial experiment, Escherichia coli, Staphylococcus aureus, and Bacillus subtilis were selected as the test strains. The Oxford cup method was used to determine the diameter of the antibacterial zone, the agar diffusion method was used to determine the minimum inhibitory concentration (MIC), and the micro-broth dilution method was used to determine the minimum bactericidal concentration (MBC). In the immune regulation experiment, the mouse macrophage strain RAW 264.7 was selected, and the levels of cytokines such as IL-1β, TNF-α, and IL-6 were measured. The results showed that the ABTS free radical scavenging rates of Chunjian sea-buckthorn puree with different oil contents and with or without manuka honey were approximately 10 100 μmol•L-1 Vc equivalent. The inhibition zone diameters against E. coli, S. aureus, and B. subtilis were all more than 9 mm. The LPS-induced increase in IL-1β and IL-6 levels was inhibited by Chunjian sea-buckthorn puree containing 6 g/100 mL oil and manuka honey. Moreover, with the increase in oil content, the antioxidant and antibacterial abilities of sea-buckthorn puree were enhanced. The in vitro antioxidant and antibacterial effects of sea-buckthorn puree were improved by increasing the oil content, and the immunomodulatory effects of sea-buckthorn puree increased with the addition of manuka honey.

Abstract:The aim of this study was to optimize the purification process for total flavonoids from the aerial parts of Tetrastigma hemsleyanum Diels & Gilg (TFATH) by using macroporous resin and to evaluate the protective effects of TFATH against carbon tetrachloride-induced acute liver injury in mice. The effects of different loading conditions and elution conditions on the purification results were investigated using single-factor experiments, and the antioxidant activity of the aerial parts of Tetrastigma hemsleyanum Diels & Gilg was determined before and after purification. TFATH were qualitatively analyzed using UPLC-ESIQTOF-MS2, and an acute liver injury model induced by carbon tetrachloride was established. The results showed that the purity of flavonoids in the purified samples increased from 8.99% to 31.38%, and the antioxidant capacity also significantly improved. Twelve types of flavonoids were identified, primarily including (iso) vitexin, (iso) orientin, and their glycosides. The animal experiment results showed that, compared with the model group, the liver index and serum ALT and AST activities of TFATH-treated mice significantly decreased by 9.74%, 12.91%, and 33.98%, respectively, and the degeneration, necrosis, and inflammatory infiltration of hepatocytes significantly improved. In liver tissue, GSH content and CAT activity increased by 54.14% and 50.88%, respectively, whereas the MDA content significantly decreased by 66.53%. In addition, with the intervention of TFATH, the expression levels of TNF-α, IL-1β, IL-6, caspase-3, Bax, and Keap1 were significantly downregulated, whereas the expression levels of Bcl-2, Nrf2, HO-1, NQO1, and GCLC were upregulated. In summary, TFATH comprehensively ameliorates acute liver injury induced by carbon tetrachloride by activating the Keap 1/Nrf 2 signaling pathway, modulating oxidative stress, alleviating inflammatory responses, reducing the expression of proinflammatory cytokines, and inhibiting hepatocyte apoptosis. The results provide a theoretical reference for the development and utilization of resources from the aerial parts of Tetrastigma hemsleyanum Diels & Gilg.

Abstract:To promote the development of whole-grain foods and low glycemic index (GI) staples, the nutritional composition, textural properties, and in vitro digestion characteristics of eight indica brown rice varieties were systematically compared with those of milled rice. The differences between these varieties and milled rice were discussed, and correlations between indicators were examined. Significant differences (P<0.05) were observed in fat, protein, and dietary fiber contents among different brown rice varieties. All brown rice varieties exhibited significantly higher (P<0.05) γ-aminobutyric acid, total free phenolics, and total free flavonoids than milled rice, accompanied by superior antioxidant capacities. The maximum DPPH and ABTS+ radical scavenging activities observed in the brown rice varieties were approximately four times and three times higher than those in milled rice, respectively. Cooked brown rice demonstrated significantly greater hardness (P<0.05), with the softest brown rice variety still showing a hardness level approximately 1.5 times higher than that of milled rice. The estimated glycemic index (eGI) of brown rice ranged from medium to high levels, with Zhongzao 39 exhibiting the lowest eGI value (61.48), equivalent to 0.8 times that of milled rice. Significant negative correlations (P<0.01) were identified between eGI values and fat, protein, and dietary fiber contents. These findings suggest that brown rice has substantial potential for enhancing nutritional value and developing low-GI functional foods, thus providing theoretical support for processing optimization, formula design, and health function evaluation of brown rice products.

Abstract:To investigate the protective effects of kaempferol-3-O-rutinoside (K3R) against H2O2-induced oxidative damage in HepG2 cells, the regulatory mechanisms of such effects were systematically analyzed using an in vitro model. After pre-treatment with 10, 20, and 30 μmol•L-1 K3R for 24 hours, the cells were exposed to 400 μmol•L-1 H2O2 for four hours. Cellular viability, reactive oxygen species (ROS) levels, oxidative damage status, and antioxidant capacity were assessed across experimental groups. Apoptosis was evaluated using Annexin V-FITC/PI staining and TUNEL assays. Western blotting was performed to analyze the expression of antioxidant proteins (HO-1 and NQO1), apoptosis-related proteins (Bax, Caspase3, and Bcl-2), and key components of the MAPK/NF-κB signaling pathway. The results demonstrated that cell viability was significantly increased to 99.93% in the K3R-protected groups, accompanied by reduced ROS levels approaching normal ranges, enhanced antioxidant enzyme activity, and effective suppression of apoptosis. HO-1, NQO1, and Bcl-2 expressions were upregulated, whereas Bax and Caspase3 expressions were downregulated. Furthermore, phosphorylation of P38, JNK, ERK1/2, and NF-κB p65 in the MAPK/NF-κB pathway was effectively inhibited. In summary, K3R alleviates H2O2-induced oxidative damage in HepG2 cells by suppressing MAPK/NF-κB pathway activation, enhancing antioxidant capacity, and regulating apoptosis-related proteins. This study provides a theoretical basis for the application of K3R in the development of antioxidant functional foods and drugs.

Abstract:To analyze the impact of the fliE gene on the persistence of Listeria monocytogenes, a fliE deletion mutant was successfully constructed using homologous recombination technology. Growth capacity assays demonstrated that the ΔfliE strain reached the stationary phase at an OD600 of 0.64, whereas the parental strain reached the stationary phase at an OD600 of 0.66. No significant difference in growth capability was observed between the parental and ΔfliE strains (P>0.05). Motility assays demonstrated that the migration diameters of the parental and ΔfliE strains in a semi-solid agar medium were 6.00 ± 0.05 mm and 6.03 ± 0.05 mm, respectively, suggesting no significant difference in motility (P>0.05). The biofilm formation capability of the ΔfliE strain was assessed using the crystal violet staining method. Compared with the parental strain, the ability of the ΔfliE strain to form mixed biofilms with Weissella confusa W4-1 and WL5-1 decreased to 71.55% and 74.77% (P<0.01), respectively. Disinfectant tolerance assays and analysis based on confocal laser scanning microscopy (CLSM) suggested that the survival ability of L. monocytogenes in mixed biofilms formed by co-culturing the ΔfliE strain with Weissella confusa was significantly reduced. These results demonstrated that deletion of the fliE gene not only affected the biofilm formation ability of L. monocytogenes but also reduced its tolerance to quaternary ammonium disinfectants. The findings of this study provide a theoretical foundation for further understanding the molecular mechanisms underlying the persistence of hypervirulent, persistent-genotype L. monocytogenes strains.

Abstract:The aim of this study was to investigate the influence of brine concentration on certain physicochemical properties and microbial community characteristics in naturally fermented mustard greens pickles from the Chaoshan region. During the fermentation stage after pre-pickling, the salt concentration of the brine was adjusted to create gradients of 3 wt.%, 4 wt.%, and 5 wt.%. Throughout fermentation, changes in brine salinity, total acidity, appearance and flavor, reducing sugar, amino acid nitrogen, total lactic acid bacteria count, and total colony count were measured, and high-throughput sequencing of the bacterial community on the pickles was performed at the end of fermentation. The results indicated that salt concentration significantly affected both physicochemical properties and microbial populations during fermentation. After 10 days of fermentation, the total acid content differed by 1.83 g.kg-1 between pickles fermented at 3 wt.% and 5 wt.% salt; the time to peak reducing sugar content differed by 3 days between these two concentrations, whereas the difference between 3 wt.% and 4 wt.% was 1.06 g.kg-1. Brine at 3 wt.% resulted in a higher proportion of spoilage and pathogenic bacteria, whereas brine at 5 wt.% partially inhibited the growth of non-halotolerant lactic acid bacteria, resulting in a lower proportion of lactobacilli (21%). Moreover, a lower salt concentration appeared to accelerate the fermentation process. Based on microbial composition and amino acid nitrogen content, brine with 4 wt.% salt was determined to be the most suitable for fermenting Chaoshan mustard greens pickles after pre-pickling. This study provides a theoretical basis for understanding the fermentation process of naturally fermented mustard greens pickles from the Chaoshan region and for selecting the appropriate salt concentration for preparing such pickles.

Abstract:Staphylococcus aureus is a prevalent foodborne pathogen. However, it has exhibited increasing tolerance to common preservatives. The aim of this study was to analyze new natural preservatives to combat this issue. In this study, sanggenon C and D, derived from mulberry trees, were investigated to understand the inhibition mechanisms involved in the cell membrane biosynthesis of S. aureus by using scanning electron microscopy, quantitative real-time PCR, and parallel reaction monitoring. The results indicated that the minimum inhibitory concentrations of sanggenon C and sanggenon D against S. aureus were 70.60 μmol•L-1 and 17.60 μmol•L-1, respectively, demonstrating significantly superior efficacy when compared with that of cinnamaldehyde. Furthermore, sanggenon D disrupted the cell structure and morphology of S. aureus. Notably, sanggenon D exhibited a stronger inhibitory effect on S. aureus than sanggenon C for the expression of genes and proteins related to phospholipid biosynthesis. In particular, sanggenon D exerted a more significant inhibitory effect on the expressions of Fab H and CdsA within the phospholipid synthesis pathway. Based on molecular docking results, the interaction between sanggenon D and PlsX probably involved the formation of hydrogen bonds at Lys290, Glu233, Gly293, and Ser294, with a greater interaction strength than that of the hydrogen bond interaction between sanggenon C and PlsX. This mechanism may account for the enhanced inhibitory effect of sanggenon D when compared with that of sanggenon C. Therefore, sanggenon D holds potential for development as a natural food preservative. These findings offer a theoretical foundation for the application of sanggenon D as a novel type of natural preservative.

Abstract:To enhance the fermentation protein yield of Auxenochlorella pyrenoidosa and its amino acid quality through combined mutagenesis, the high-protein, chlorophyll-deficient mutant strain CX41, previously obtained by the research team, was used as the original strain. Combined mutagenesis was conducted using ethyl mesylate and atmospheric and room temperature plasma, followed by high-throughput screening through a microbial microdroplet culture system and 48-well plate cultivation. Subsequently, after secondary screening via 250 mL shake flask cultivation, the mutant strain Y11 was ultimately obtained. Under dark fermentation conditions at 30 ℃ and 160 r•min-1 for 96 h in basal medium containing 30 g•L-1 glucose and 3.75 g•L-1 sodium nitrate, the biomass, protein content, and yield of Y11 reached 9.05 g•L-1, 55.54 g/100 g dry weight, and 1.26 g•(L•d)-1, respectively, which were significantly higher than those of the original strain CX41, with increases of 21.15%, 25.60%, and 51.81%, respectively. The amino acid score (94.41) and total branched-chain amino acid content (6.96 g/100 g dry weight) also improved by 3.49 points and 27.35%, respectively. Moreover, compared with CX41, the lutein content (1.12 mg•g-1), yield (10.10 mg•L-1), and productivity (2.52 mg•(L•d)-1) significantly increased by 4.67%, 26.88%, and 26.63%, respectively. This study provides a theoretical basis and technical support for the breeding of high-quality microalgal strains by using combined mutagenesis and high-throughput screening techniques.

Abstract:To improve the physical properties of rice starch (RS) and expand its application fields, analytical techniques such as rheological analysis, scanning electron microscopy, low-field nuclear magnetic resonance, and X-ray diffraction were used to systematically examine the influence of curdlan (CL) addition on the structure and properties of the thermally irreversible gel of CL-RS blends. When the CL amount reached the threshold of 0.60%, compared with the control group, the gelatinization temperature decreased by 1.69 ℃, retrogradation viscosity increased by 25%, syneresis rate reduced by 47.73%, and transverse relaxation time T22 decreased by 58.01% to 6.45 ms. Compared with the group with 0.40% CL addition, the peak value of the storage modulus increased by 40.20%, the G′ value at the end of cooling increased by 21.46%, and chewiness improved by 24.76%. When the CL addition amount was 0.60% or less, retrogradation viscosity, viscoelastic modulus at each phase-change temperature node, chewiness, and the ratio of the bound-water peak area (A21) increased significantly with the increase in CL addition amount, whereas the transverse relaxation times T22 and T23 of water molecules and gel syneresis rate consistently decreased. The microstructure exhibited a decrease in porosity along with an improvement in the uniformity of its distribution. When CL addition exceeded the threshold (0.80%), a reduction of 11.37% in G′ at the end of cooling and a 42.89% decrease in chewiness were observed, accompanied by transformation of the microstructure from a porous network to a densely layered structure. The mechanism was attributed to CL-induced enhancement of hydrogen-bond crosslinking density, which facilitated the formation of stable threedimensional RS networks. In conclusion, properties of the RS-based blend gel were effectively regulated by the threshold effect of CL addition amount. These findings provide a theoretical reference for the development of new foods with RS-based heterogeneous polysaccharide blend systems.

Abstract:To investigate the effects of acidic calcium sulfate (ACS) treatment on black mold infection and storage quality of gray jujube, in vitro assays were conducted to evaluate the inhibitory effects of ACS on Aspergillus niger colony growth, spore germination, and mycelium development in Xinjiang gray jujube. Further, in vivo vacuum-impregnation treatments were performed to examine their effects on the storage quality parameters of gray jujube. The results showed that ACS treatment had a significant inhibitory effect on A. niger colony formation, spore germination, and mycelial development, with ACS-10-1 (10 000 mg•L-1) exhibiting 100% inhibition in all cases. Scanning electron microscopy showed that ACS significantly disrupted the microstructure of A. niger. ACS could effectively reduce the incidence of black mold infection in grey jujube. Compared with the CK group, ACS-10-1 exhibited 100% inhibition. Vacuum impregnation with ACS also significantly reduced natural decay, slowed moisture loss, maintained total soluble solids, titratable acid (TA), and ascorbic acid (AsA) levels, and decreased surface microbial counts. After 60 days of storage, natural decay was 39.29% lower in the ACS-treated group than in the CK group; moisture content and TA and AsA levels were 3.14%, 8.13% and 2.54% higher, respectively, and total colony counts as well as mold and yeast counts decreased by 1.13 and 1.43 log10CFU/g, respectively. In summary, vacuum impregnation with ACS is a safe and effective postharvest sanitizing and preservation method for gray jujube. The results provide a theoretical basis for quality preservation technology in the Xinjiang gray jujube industry.

Abstract:To evaluate the effects of different thawing methods on the edible quality of Micropterus salmoides and select the optimal thawing method, changes in the edible quality of fish meat thawed by different methods and that of fresh fish meat were compared by measuring basic physicochemical indexes such as water-holding capacity and texture properties and by evaluating flavor. The results showed that the fish meat thawed by water bath had the best water-retention capacity, with the water-retention rate reaching 81.10%, and the brine-thawing group had the highest thawing loss rate (P<0.05), reaching 13.83%. The water migration of fish meat in the water-bath thawing group was close to that of the fresh fish group. No significant difference was observed in pH values among the different thawing groups (P>0.05). In terms of textural properties, the brine-thawing group was closer to the fresh fish group, followed by the water-bath thawing group. The sensory scores of the water-bath thawing group and ultrasonic thawing group were higher (40.70 and 39.85, respectively), whereas the brine-thawing group exhibited the lowest sensory score (37.85). The contents of total amino acids, umami amino acids, and sweet amino acids in the fish meat of the water-bath thawing group were the highest (251.79, 162.44, and 56.43 μg•g-1, respectively), and this group also exhibited higher contents of 5′-inosinic acid (20.70 mg/100 g) than the other thawing groups. The organic acid contents were significantly lower in all thawing groups than in the fresh fish group (P<0.05). In conclusion, under the premise of ensuring edible quality, water-bath thawing is more suitable for thawing Micropterus salmoides.

Abstract:To understand the impact of storage conditions on the product quality of different types of food for special medical purposes (FSMP), changes in the content of nutritional components in FSMP were investigated under conditions of high temperature, high humidity, and light exposure. Five commercially available FSMPs were used as raw materials and stored under conditions of high temperature, high humidity, and light exposure for five days and 10 days, and changes in their nutrient contents were determined. The results indicated that high temperature, high humidity, and light exposure all caused a decrease in vitamin C content. Among them, the influence of light exposure was the most evident. After 10 days of storage, vitamin C content in the formula for preterm or low-birth-weight infants decreased to 94.54 mg/100 g, with an attenuation rate as high as 9.43%. High Ltemperature had the most pronounced effect on vitamin A content in amino acid formula food, which, after 10 days of storage, decreased to 2.20 mg RE/100 g, with an attenuation rate of 7.56%. Under high-temperature and high-humidity conditions, attenuation of vitamin B1 content in all samples was less than 3%. Light exposure exhibited the most evident effects on vitamin A and vitamin D contents in the extensively hydrolyzed formula, with attenuation rates reaching 3.62% and 3.80%, respectively, after 10 days of storage. In addition, light exposure demonstrated the most obvious effect on vitamin B2 and vitamin K1 contents in the formula for preterm or low-birth-weight infants, and the attenuation rates reached 5.43% and 8.68%, respectively, after 10 days of storage. In conclusion, high temperature, high humidity, and light exposure all have varying degrees of influence on FSMP. This study provides valuable insights for ensuring the quality and stability of FSMP products in different environments.

Abstract:To investigate changes in noodle quality after heat-moisture treatment of wheat, the effects of wheat initial moisture content (14~22%), heat-moisture treatment temperature (45~85 ℃), and heat-moisture treatment duration (15~90 min) on wheat gluten protein composition and subunit ratio, as well as the cooking and texture characteristics and sensory quality of noodles, were evaluated. Response surface methodology was used to predict the optimal process of wheat heat-moisture treatment. The results indicated that high-temperature, long-duration heat-moisture treatment contributed to significantly reduced glutenin content, increased prolamin content, reduced glutenin-to-prolamine ratios, significantly decreased levels of high-molecular-weight glutenin subunits and low-molecular-weight glutenin subunits, and significantly increased γ-subunit levels. Heat-moisture treatment at a higher intensity (moisture content of 22%, temperature >75 ℃, and duration >60 min) led to an increase in noodle cooking loss, with lower levels of hardness, chewiness, elasticity, and sensory scores. The optimal conditions for heat-moisture treatment were found to be a temperature of 56 ℃, initial wheat moisture content of 18%, and duration of 35 min. Under these conditions, the sensory score of the noodles was 83.8, cooking loss rate was 6.02%, and overall score was 0.93. Compared with the untreated group, the hardness and chewiness of the noodles slightly increased, water absorption rate increased by 7.63%, and no significant difference in sensory scores was identified. In conclusion, appropriate heat-moisture treatment of wheat can improve the quality of noodles. This study provides a reference for using heat treatment to stabilize or improve the quality of wheat.

Abstract:To develop a highland barley-based whole-grain biscuit with improved palatability and functional benefits for dyspepsia that embodies the concept of medicinal-food homology, solid-state fermented highland barley whole-grain powder (processed with Lactobacillus acidophilus) was used as a primary ingredient, and rheological and thermal properties of the dough, as well as texture and sensory scores of the biscuit, were measured. Response surface methodology (RSM) was used to optimize the formula of the biscuits. After the addition of HMSC, powdered sugar, and NaHCO3, dough elasticity (G') and viscosity (G") increased with the increase in frequency, and viscosity decreased with the increase in shear rate. With the increase in the mass fractions of powdered sugar and NaHCO3, the gelatinization temperature increased, and the enthalpy change decreased. After the addition of HMSC, the hardness of biscuits first decreased and then increased, whereas viscosity and chewiness significantly increased (P<0.05). After the addition of powdered sugar and NaHCO3, the hardness, brittleness, viscosity, and chewiness of the biscuits significantly decreased (P<0.05), whereas the samples treated with NaHCO3 exhibited increased chewiness. RSM results showed that mass fractions of 7.7%, 11.3%, and 0.64% for HMSC, powdered sugar, and sodium bicarbonate, respectively, yielded the highest sensory score for the biscuits. A crispy biscuit with digestive-enhancing effects was successfully developed, providing novel insights for the development of homology-of-medicine-and-food products and whole-grain foods.

Abstract:Vacuum cooling often results in the penetration of pathogenic bacteria into vegetable stomata, making conventional washing methods ineffective. To remove Escherichia coli that penetrates the stomata of lettuce, a vacuum-ultrasonic (VC-US) composite cleaning method was used at three evacuation rates: α1 (0.467 3/min), α2 (0.323 5/min), and α3 (0.161 7/min). The effectiveness of VC-US and its impact on lettuce quality were evaluated by measuring the colony counts and relevant physicochemical properties before and after cleaning as well as the changes in these indicators during storage. The results showed that the α3 group reduced E. coli counts inside lettuce from 4.33 to 1.47 log10 CFU/cm2, which was significantly more effective than the α1 and α2 groups, whose E. coli counts were reduced to 2.03 and 1.92 log10 CFU/cm2, respectively (P<0.05). After two days of storage, L* and b* values of the α3 group were significantly lower than those of the α1 group (P<0.05), whereas the a* value was slightly higher; however, no significant difference was detected when compared with the α2 group (P>0.05). Chlorophyll and vitamin C contents showed no significant differences among the three treatment groups (P>0.05). Additionally, the weight loss rate was significantly lower in the α3 group (-19.89%) than in the α1 (-0.18%) and α2 (-19.03%) groups (P<0.05). Collectively, these findings indicate that VC-US cleaning with a lower evacuation rate is more effective in removing E. coli inside lettuce without significantly affecting its quality, thus providing theoretical support and practical value for the application of VC-US technology in removing internal pathogens from vegetables.

Abstract:To achieve efficient utilization of Ganoderma lucidum polysaccharides (GLP), the extraction process of polysaccharides from Ganoderma lucidum fruiting bodies was optimized through single-factor and response surface methodology. Subsequently, the in vitro antioxidant capacity of GLP was determined. Based on these findings, an oxidative damage model was established using H2O2-induced HepG2 cells to investigate the protective effects of GLP against cellular oxidative stress. The results demonstrated that the optimal extraction conditions were as follows: extraction temperature of 88 ℃, water extraction time of 2.5 h, liquid-to-solid ratio of 41:1 (mL•g), and ultrasonic treatment duration of 40 min. Under these conditions, the polysaccharide yield rate was 3.05%. At a concentration of 1 mg.mL-1, GLP exhibited remarkable scavenging activities against oxhydryl, 1,1-diphenyl-2-dinitrophenylhydrazine, and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), with scavenging rates reaching 79.49%, 70.55%, and 79.61%, respectively. Cellular experiments revealed that 8 μg.mL-1 GLP was able to restore cell viability to nearly 100%. Compared with the model group, all GLP treatment groups showed increases of 28.44%~61.61% in superoxide dismutase (SOD) and 58.61%~101.75% in glutathione peroxidase (GSH-Px), as well as reductions of 14.28%~32.89% in malondialdehyde (MDA) levels. Furthermore, GLP treatment effectively reduced reactive oxygen species accumulation and significantly downregulated the expression of Nrf2 and HO-1 genes, while upregulating Keap1 gene expression (P<0.01). The protective effects against oxidative stress were mediated through activation of the Keap1/Nrf2 signaling pathway. This study provides a valuable reference for the development of GLP extraction methods and antioxidant functional products.

Abstract:To analyze the accumulation of carotenoids during the development of sweet potato tubers, color characteristic values as well as carotenoid composition and content in sweet potato tubers with different flesh colors on the 45th, 75th, 105th, 135th, and 165th days after transplanting were measured using a chroma meter and ultra-high performance liquid chromatography. The results showed that the total content of carotenoids (299.07 μg•g-1) in orange-red-flesh sweet potatoes (ORFSPs) was much higher than those in other varieties. During the developmental process, the total amount of carotenoids accumulated continuously in the early stage, but most varieties showed a significant decrease on the 165th day. A total of 11 types of carotenoid monomers were detected in eight sweet potato varieties. Among them, β-carotene, violaxanthin, neoxanthin, antheraxanthin, and lutein exhibited high content and remained stable throughout the development of sweet potatoes. Yellow-flesh sweet potatoes (YFSPs) exhibited high levels of violaxanthin and antheraxanthin, whereas orange-flesh sweet potatoes (OFSPs) mainly accumulated lutein and β-carotene. The content of β-carotene in ORFSP accounted for 81.20%~94.38% of total carotenoid content, making β-carotene the most important carotenoid in sweet potatoes. Carotenoids in sweet potatoes were negatively correlated with brightness (L*) and chroma angle (H*), but positively correlated with redness (a*) and color saturation (C*). Neoxanthin was significantly positively correlated with yellowness (b*). In summary, OFSPs and ORFSPs possess more carotenoids, ORFSPs have higher carotenoid concentrations, and carotenoid monomers containing oxygen functional groups in YFSP account for a relatively high proportion in the carotenoid composition. The results provide a theoretical basis for the study of nutritional quality and variety breeding of sweet potatoes.

Abstract:Differences in the edible quality of Jingpo Lake grass carp (JPGC) and culture grass carp (CGC) under different frying conditions were compared. Color difference, textural properties, sensory evaluation, and other indicators were measured to select the optimal frying temperature and time. Secondary structures and microstructures of the selected samples were compared and analyzed. The optimal conditions for traditional frying were 200 ℃ for 4 min, whereas those for air frying were 200 ℃ for 20 min. The airfried JPGC was reported to show superior edible quality, with a measured shear force of 2 626.46 g, moisture content of 56.13%, and immobile water content of 88.31%. Compared with traditional frying, air frying retained more internal moisture, maintained a crispy exterior and tender interior texture, and received the highest sensory evaluation scores. The air-fried JPGC achieved a similar fried texture with a fat content of 0.30% and a lower degree of fat oxidation. Fourier-transform infrared spectroscopy analysis of the secondary structure of myofibrillar proteins revealed that JPGC maintained a consistently higher β-sheet content than CGC under both frying conditions. Microstructural examination revealed that the muscle fibers of air-fried JPGC were the most densely and orderly arranged, effectively slowing down juice loss. Air-fried grass carp achieved an edible quality comparable to that of traditionally fried grass carp. JPGC exhibited better muscle quality during processing than CGC. In summary, this study provides a theoretical foundation for the high-value utilization of grass carp resources in the volcanic barrier lakes of Mudanjiang City.

Abstract:To improve the quality characteristics of mung bean noodles and develop a legume staple food with a low glycemic index (GI), noodles were prepared using different proportions of mung bean ultrafine powder and wheat flour. The sensory quality, rheological properties, cooking characteristics, texture, microstructure, and starch components of the noodles were evaluated, and the GI value of the noodles was determined through human testing. The results indicated that the sensory score of the noodles was higher when 30% or 45% mung bean ultrafine powder was added. Rheological analysis showed that a higher proportion of mung bean ultrafine powder contributed to higher storage modulus (G') and higher loss modulus (G") of the dough, indicating certain levels of viscoelasticity. When 45% green bean ultrafine powder was used, the starch particles were tightly wrapped, and the internal microstructure of the noodles was relatively dense and uniform, with a hardness of 11.58 N, elasticity of 1.35 mm, cooked breakage rate of 4.34%, and satisfactory cooking quality. The addition of mung bean ultrafine powder effectively increased the content of slowly digestible starch and resistant starch in the noodles and reduced the estimated GI value of the noodles. Human blood glucose testing revealed that the GI value of noodles with 45% mung bean ultrafine powder was 49.93, classifying the noodles as low GI food. This study is of great significance for upgrading the deep processing technology of mung beans and developing healthy low-GI staple foods.

Abstract:To screen tea cultivars suitable for tencha production in the area of Jiangsu, quality differences of seven tencha varieties were compared through the detection of quality components, analysis of catechin quality index, and correlation analysis of principal components. The results showed significant differences (P<0.05) in the content of quality components and catechin quality index among seven tencha varieties produced from seven tea cultivars that underwent the same shading management and processing conditions. Among the samples, the Maolu landrace exhibited the highest mass concentrations of proteins (31.74%), tea polyphenols (14.10%), SDF (4.28%), total chlorophyll (4.89 mg•g-1), chlorophyll b (2.82 mg•g-1), vitamin C (5.72 mg•g-1), and GA (2.32%) as well as the highest CAI (15.69), whereas its IDF/SDF ratio was minimum (7.58). Principal component analysis showed that water extract, soluble sugar, catechin components, vitamin C, SDF, and IDF were the characteristic components of tencha quality, reflecting the quality differences of tencha produced from different tea cultivars. The Maolu landrace had the highest comprehensive score of 1.17, indicating the superior quality of tencha produced from the Maolu landrace in Jiangsu. This study provides a significant theoretical basis for screening tea cultivars suitable for tencha production.

Abstract:Amadori rearrangement products (ARPs) have promising application potential in the food industry as novel food flavoring agents. The aim of this study was to investigate the effects of cysteine-glucose ARPs as food-flavoring agents and clarify their specific effects on food flavors by adding cysteine-glucose ARPs during the production process of biscuits. The volatile aroma compounds of the biscuits were analyzed using electronic nose detection and gas chromatography-mass spectrometry (GC-MS). A total of 30 different volatile compounds were detected using GC-MS. Compared with the blank group, the varieties of pyrazine volatiles in the treatment group increased from two to 10, the number of thiophene volatiles increased from zero to three, and the number of furan volatiles increased from zero to two. Biscuits with different doses of ARPs exhibited varied aroma characteristics, with sulfur-containing substances, organic compounds, and terpenes being major differential compounds. Among them, the addition of 2.4% ARPs (based on the mass of flour used to prepare biscuits) to 33 g of biscuits was more favorable to the formation of thiophenes and other compounds. The increase in the variety and content of these compounds enhanced the richness of biscuit flavors, such as introducing a meat aroma. The main aroma compounds of biscuits with cysteine-glucose ARPs were identified, providing a scientific basis for their application as meat-flavoring agents.

Abstract:To investigate the effects of different mass fractions of patchouli, perilla, and clove extracts on the fishy flavor of pre-prepared dishes with golden pomfret, color evaluation, thiobarbituric acid reactive substances, fishy flavor values, sensory evaluation, electronic nose detection, and headspace solid phase microextraction-gas chromatography-mass spectrometry (HS-SPMEGC-MS) were used to compare the deodorization effects of these extracts and examine the changes in flavor compounds in golden pomfret. The results showed that the ΔE values of steamed fish, which underwent immersion in the three natural extracts, increased with the mass fractions of the extracts. All treatments with patchouli, perilla, and clove at a mass fraction of 5% effectively inhibited fat oxidation, and the corresponding treated fish received the highest evaluation scores. The response values of the electronic nose sensors W2W, W1W, and W5S were lower than those of the blank samples, suggesting that the deodorization treatment was effective in reducing nitrogen oxides and sulfides. Principal component analysis showed clear separation, and the electronic noses could effectively distinguish odor differences among the different treatment groups. A total of 64 volatile compounds were detected using GC-MS, with hexanal, heptanal, octanal, and nonanal all exhibiting odorant activity values greater than 1; this indicated that they were the main compounds causing the fishiness of golden pomfret. After deodorization treatment, the contents of these compounds significantly decreased (P<0.05). The clove group exhibited the lowest aldehyde level (181.58 μg•kg-1), suggesting that it was the most effective in deodorization. In conclusion, all three natural extracts can effectively improve the flavor of golden pomfret, and the 0.5% clove extract demonstrated the optimal deodorization effect. The results of the study provide a reference for enhancing the flavor of pre-prepared aquatic dishes.

Abstract:A comparative investigation of roasting methods by using catalytic infrared (CIR), electric infrared (EIR), and hot air (HA) was conducted to evaluate their distinct impacts on coffee bean flavor profiles through integrated analytical techniques, such as high-performance liquid chromatography, electronic nose, and headspace solid-phase microextraction gas chromatographymass spectrometry (HS-SPME-GC-MS). Significant inter-method variations (P<0.01) were identified in the contents of total sugars, polyphenols, lipids, proteins, chlorogenic acid, and trigonelline, whereas total acidity and caffeine levels remained statistically comparable (P>0.01). Orthogonal partial least squares discriminant analysis (OPLS-DA) of electronic nose data showed a prediction reliability of R2=0.858, whereas GC-MS characterization revealed 196 volatile compounds spanning 15 classes, with 104 shared volatiles establishing the most robust OPLS-DA model (R2=0.926). Six pivotal aroma discriminators-2,3-butanedione, 2,3-pentanedione, furfuryl acetate, 3,5-diethyl-2-methylpyrazine, methyl isovalerate, and hydroxyacetone-were quantitatively prioritized via odor activity value assessment, all demonstrating elevated concentrations in CIR-processed beans. Energy efficiency analysis further highlighted CIR’s superiority, exhibiting 73.87% and 23.68% cost reductions relative to HA and EIR, respectively. These findings collectively validate CIR as a dual-advantage roasting modality, simultaneously enhancing flavor complexity through targeted volatile compound preservation and optimizing energy utilization, thereby providing actionable insights for developing precision roasting technologies in specialty coffee manufacturing.

Abstract:To improve the nutritional value of traditional fresh and wet rice noodles, fresh and wet rice noodles with deodorized spirulina were developed by using spice extract to remove the “fishy smell” of spirulina. The cooking quality, texture, in vitro digestion, and flavor characteristics of the rice noodles were evaluated. The results showed that the water extract of lemon (with a mass fraction of 0.25%) in combination with licorice (with a mass fraction of 0.2%) had the best deodorizing effect, yielding the highest sensory score (24.67) for rice noodles. The optimal conditions were as follows: 1.4% addition of spirulina, rice slurry fineness of 80 mesh, and a material-to-water ratio of 1:1. The cooking loss rate of the deodorized spirulina rice noodles was 9.03%. The breakage rate was significantly increased by 11.88%, the water absorption rate was significantly increased to 4.24%, the aging degree was higher, and flavor absorption was stronger. However, the breakage rate and RS content (47.40%) were significantly higher than those of ordinary rice noodles (41.51%), and the nutritional value was higher. A relatively large difference in flavor composition was observed between the deodorized spirulina rice noodles and spirulina. Specifically, the flavor compounds of rice products, such as nonanal, hexanal, (Z)-oct-2-enal, decanal, benzaldehyde, and ethyl hexanoate, were retained, and the relative contents of volatile compounds that caused the unpleasant odor in spirulina, such as hexanal, trans, trans-2,4-decadienal, 1-octen-3-ol, β-ionone, and 2,5-dimethylpyrazine, were reduced to 3.99%, 0.47%, 2.44%, 5.02%, and 0.66%. In conclusion, rice noodles with deodorized spirulina exhibited a high breakage rate, but they demonstrated superior cooking-loss rate, flavor absorption, and in vitro digestion characteristics as well as unique flavor features tha t indicated strong potential for broader application.

Abstract:To investigate flavor changes in blueberry fruits during the green fruit stage, mid-ripening stage, and mature stage, headspace-solid-phase microextraction-gas chromatography-quadrupole flight time mass spectrometry in combination with odor activity value was used to analyze variations in the composition and content of volatile compounds of four blueberry varieties (LBS, ZB, FX, and SXL). The results showed 191 compounds, including 40 key aroma compounds, with terpenes being the predominant aroma components in blueberry fruits and exhibiting the highest number (53) and concentrations (42 455.36 μg•kg-1). Among the three developmental stages, the mid-ripening stage was identified as a critical phase for flavor transformation in blueberry fruits. Specifically, 149 (34 723.06 μg•kg-1), 128 (31 417.00 μg•kg-1), and 114 compounds (32 547.89 μg•kg-1) were detected in the green fruit, mid-ripening, and mature stages, respectively. In terms of compound concentrations, aldehydes and alcohols gradually increased, whereas ketones and esters gradually decreased. However, the concentration of terpenes varied differently across cultivars. The common key differential marker compounds in the varieties at the three developmental stages were hexanal and linalool. Flavor profile analysis indicated that LBS, FX, and SXL predominantly exhibited a floral aroma throughout development, whereas ZB displayed a strong floral aroma during the green fruit stage that evolved into a unique mixed aroma characterized by floral and herbal aromas as the fruits matured. This study provides a theoretical foundation for understanding the formation and variation of flavor during the development of blueberry fruits.

Abstract:A novel fluorescent biosensor was developed for the quantitative detection of histamine (Hist), cadaverine (Cad), and putrescine (Put) in seafood. This biosensor is based on the composite material of N,S co-doped carbon dots and manganese dioxide nanoflowers (N,S-CDs@MnO2) and diamine oxidase (DAO). The successful synthesis of N,S-CDs@MnO2 was confirmed through characterization of the synthetic material, and quantitative detection of target biogenic amines was performed by optimizing the detection conditions of the N,S-CDs@MnO2-DAO sensor. The results showed that the linear detection ranges of the fluorescence biosensor for Hist, Cad, and Put were all 0~200 μmol•L-1, and the detection limits were 0.59, 0.65, and 0.85 μmol•L-1, respectively, indicating good method sensitivity. No significant response was observed to amino acids, inorganic salt ions, or reducing substances with potential interference, suggesting good method selectivity. For actual seafood samples, the spiking recovery rate was between 93.17% and 105.34%, and the relative standard deviation was less than 5.83%. For fish, shrimp, and shellfish samples, relative deviation between the detection results of the sensor and HPLC was less than 10%, indicating good accuracy of the method. Therefore, the developed N,S-CDs@MnO2-DAO fluorescent biosensor had good sensitivity, selectivity, and accuracy for the detection of Hist, Cad, and Put. It is an effective tool for the safety and quality control of seafood.

Abstract:To investigate differences in the inorganic element content and safety of insect tea from various production areas in Guangxi, inductively coupled plasma mass spectrometry was used to determine the contents of 29 inorganic elements, such as potassium, calcium, and magnesium, in insect tea from five major production areas in Guangxi (i.e., Sanjiang, Longsheng, Rong’an, Pingnan, and Wuzhou). Multiple statistical analyses were conducted, including variance analysis, Duncan’s multiple range test, Pearson’s correlation analysis, and principal component analysis (PCA), to analyze differences in the contents of inorganic elements in insect tea from different production areas. The results showed complex and diverse differences (P<0.05) in the contents of various inorganic elements in insect tea from different production areas. Correlation analysis revealed that some elements in Guangxi insect tea were significantly or extremely significantly correlated. Specifically, extremely significant positive correlations (P<0.01) were found between boron and potassium, calcium and titanium, and zinc and sodium. Significant positive correlations (P<0.05) were found between calcium and strontium, aluminum and copper, manganese and nickel, strontium and titanium, barium and boron, as well as barium and strontium. In contrast, significant negative correlations (P<0.05) were observed between magnesium and barium as well as magnesium and strontium. Through PCA, three principal components were extracted, with a cumulative variance contribution rate of 93.26%. Multiple elements, including potassium and calcium, were determined to be the main characteristic elements contributing to the differences in the composition of inorganic elements in insect tea from different production areas. Based on the principal component score plot, five major production areas of insect tea were effectively distinguished. In terms of safety assessment, although the contents of heavy metals in the insect tea samples were not found to exceed the standards for tea, the contents of lead and chromium in insect tea from the Sanjiang production area were relatively high. These results provide a theoretical basis and data support for the origin identification, quality evaluation, and quality control of insect tea in Guangxi.

Abstract:To achieve rapid and highly sensitive detection of glucose, two-dimensional carbon-based nanomaterials functionalized edge-modified graphene (FG) were used as a conductive carrier and glucose oxidase (GOx) as a biorecognition molecule to construct a high-performance electrochemical biosensor for glucose detection (GCE/FG/GOx/CS). The electrochemical sensing performance of GCE/FG/GOx/CS electrodes was investigated using cyclic voltammetry and time-current methods. The sensing electrodes showed good electrosensing performance, high sensitivity (46.85 μA•mmol•L-1cm-2), and a wide linear detection range (0.05~1.60 mmol•L-1) for glucose, with a detection limit as low as 2.37 μmol•L-1. In addition, the electrode showed good selectivity, reproducibility (n=7, relative standard deviation RSD=2.05%), cycling stability, and storage stability (97.09% retention of response current after one week). The recoveries were 98.5%~104.4% for glucose determination in actual beverage samples. The method is simple, highly selective, and sensitive, providing a theoretical basis for the rapid detection of glucose content in food.

Abstract:Inulin, protein, total polyphenols, and ash are important physicochemical components of the Jerusalem artichoke. They have an impact on Jerusalem artichoke’s processing and nutritional characteristics. Traditional detection methods for these components often require a large number of chemical reagents and high-standard equipment. To achieve rapid prediction of the main physicochemical indicators in the Jerusalem artichoke, 56 Jerusalem artichoke samples were examined in this study. Spectral data were collected in the range of 900~2 500 nm by using a near-infrared (NIR) spectrometer, and partial least squares regression prediction models were established in combination with the measured contents of inulin, protein, total polyphenols, and ash. The results showed that, after outlier elimination, spectral preprocessing, and characteristic band screening, prediction correlation coefficients (R2p) for the optimal quantitative models of inulin, protein, total polyphenols, and ash were 0.869 5, 0.930 7, 0.943 3, and 0.920 6, respectively. The corresponding root mean square errors of prediction were 2.237 2 g/100 g, 0.363 4 g/100 g, 0.107 7 mg.g-1, and 0.158 1 g/100 g, respectively, indicating good predictive ability of the models. External validation showed no significant difference (P>0.05) between the detection results obtained using NIR spectroscopy and standard chemical methods. This study provides a theoretical basis for the application of NIR in the rapid prediction of physicochemical components in the Jerusalem artichoke.

Abstract:A gas chromatography-internal standard method was developed to measure the contents of fatty acids in four types of pre-prepared foods. The food samples were hydrolyzed with hydrochloric acid, extracted with ether-petroleum ether, saponified with 2% sodium hydroxide methanolic solution, and methylated with 15% boron trifluoride methanolic solution. Then, they were diluted with isooctane and layered with saturated sodium chloride aqueous solution. Finally, water was removed with anhydrous sodium sulfate, and the upper layer was filtered through a 0.45 μm membrane. Separation was performed using a DB FastFAME (90 m×0.25 mm, 0.25 μm) chromatographic column with a gradient temperature program, and an internal standard method was used for quantification. Under the established conditions, 36 fatty acids were effectively separated. Good linearities were observed in a certain range, and the correlation coefficients were higher than 0.99. The detection limits and quantification limits were 3~6 mg/100 g and 10~20 mg/100 g, respectively. Validation by spiking showed that the average recoveries at three levels ranged from 72.43% to 94.54% and relative standard deviations ranged from 2.84% to 8.71%. The proposed method demonstrated high accuracy, good reproducibility, and a low cost for detection, thus proving effective for measuring fatty acid content in pre-prepared food. Fatty acid content was measured in four pre-prepared foods: Yu Xiang shredded pork, braised lion’s head meatballs, black pepper beef strips, and braised chicken with yellow sauce. This method can be used to accurately determine fatty acid content in various pre-prepared foods. It provides technical support for the market supervision of pre-prepared dishes.

Abstract:Bone health is vital throughout the life cycle of an individual. From birth to death, calcium remains essential to maintain bone health. Similarly, strontium, another element essential to bone health, plays a role across all stages of the human lifespan. As an essential trace element in the human body, strontium has various biological effects, such as promoting bone formation, inhibiting bone resorption, improving myocardial function, and promoting vascular regeneration, as well as bactericidal, anti-inflammatory, and antioxidant functions. Strontium helps strengthen bones, prevent and treat osteoporosis and fractures, and alleviate conditions such as hypertension. Strontium is widely distributed in nature, but its distribution across China is highly uneven. Individuals in areas with low strontium content should supplement their dietary intake of strontium in a timely manner. This study reviews the basic characteristics, intake methods, safety, biological functions, and metabolism of strontium, its relationship with calcium, underlying diseases of middle-aged and elderly individuals, as well as the feasibility of developing strontium-enriched milk. The purpose of this study is to provide a dietary reference for improving the bone health of Chinese people.

Abstract:Bifidobacterium, as a crucial probiotic, has been proven to play a pivotal role in maintaining intestinal microecological balance, enhancing immunity, and promoting nutrient absorption. Recently, Bifidobacterium-fermented lysates (BFL) have garnered attention because of their remarkable antioxidant capacities, particularly their ability to scavenge free radicals and protect cells from oxidative damage; thus, BFL exhibit potential for anti-aging, anti-inflammatory, and anti-tumor applications. This is a review of the antioxidant properties of Bifidobacterium and BFL, including in vitro and in vivo antioxidant activity assessment methods and experimental models, identification of antioxidant components, and their mechanisms of action. Furthermore, the application prospects of BFL in the food industry, cosmetics, and medical fields have been analyzed. Additionally, the article outlines future research directions regarding BFL in the quantitative analysis of active ingredients, clinical safety assessment, and optimized preparation processes, to provide novel insights into the development and industrial application of natural antioxidants.

Abstract:Chilled poultry and livestock meat refers to meat that, following the slaughter of live animals under stringent inspection and quarantine protocols, undergoes a controlled cooling process to reduce its core temperature to 0~4 ℃. This temperature is consistently maintained during transportation and storage in accordance with good operational practices and hygiene standards. Chilled meat with texture, nutritional value, and taste closely resembling those of fresh meat is becoming increasingly popular among consumers. However, low temperatures during the storage and transportation of chilled meat cannot completely prevent the growth of microorganisms, and contamination from external sources can lead to rapid spoilage. This presents a significant challenge for the broader marketability of chilled meat. To address these issues and ensure the quality and safety of chilled livestock and poultry meat, governments have established relevant regulations and operational standards. Additionally, they encourage research into preservation technologies, including bacterial reduction, bacteriostasis, and enzyme inactivation methods, to extend the shelf life of chilled meat. In this paper, the safety standards for chilled meat, including standards related to bacterial reduction and bacteriostasis, have been reviewed, and current preservation techniques are evaluated. By comparing the standards set by various organizations and summarizing recent advancements in preservation technologies, this study provides valuable insights into the development and standardization of the domestic chilled meat industry.

Abstract:Plant polyphenols and polysaccharides exhibit a range of biological activities, such as antioxidant, anticancer, hypoglycemic, and immunomodulatory effects. However, the bioavailability of polyphenols is often hindered by challenges during digestion, such as poor intestinal absorption and limited systemic availability. Recent research has shown that polyphenols can form stable complexes with polysaccharides through molecular interactions, which not only enhance the solubility and gastrointestinal stability of polyphenols but also improve their functional properties in combination with polysaccharides. This review systematically examines the mechanisms underlying the formation of polyphenol-polysaccharide complexes, focusing on both non-covalent and covalent binding interactions. The regulatory effects of these molecular interactions on the following four key areas have been thoroughly discussed: enhancement of polyphenol bioavailability (through improved solubility and stability); improvement of polysaccharide functional properties (including viscosity, crystallinity, rheological properties, emulsifying capacity, and stability); synergistic biological activities of the complex system (such as antioxidant and anti-inflammatory as well as regulation of glucose and lipid metabolism); and impact on gut homeostasis (including gut microbiota composition, microbiota-derived metabolites, and gut barrier integrity). This study provides a novel approach and theoretical framework for the development of precision nutrition delivery systems based on polyphenol-polysaccharide molecular interactions as well as the development of functional food ingredients.

Abstract:Effective control or inactivation of foodborne pathogens is an important process to ensure product microbiological safety and consumer health. To address food safety issues and extend product shelf-life to obtain high-quality or value-added products, the food industry is adopting emerging thermal and non-thermal technologies. The inactivation mechanism of these technologies is mainly achieved by destroying the cellular morphology and molecular structure required by microorganisms to maintain normal physiological functions. Therefore, clarifying the mechanism of action is important for the process optimization and application of these technologies. This review provides an overview of the potential risks of several common foodborne pathogens, highlights the application of several typical new technologies (ohmic heating, microwave heating, pulsed electric field, cold plasma, etc.), illustrates the inactivation mechanisms of these technologies at the cellular and molecular levels in detail, and indicates the current problems and future challenges of these novel technologies in food sterilization processing. The conclusions suggest that a systematic analysis of thermal and non-thermal effects and their inactivation mechanisms remains a challenge. Although different foodborne pathogens share similarities in cellular structure and defense and stress mechanisms, they differ in their resistance to the physical environment. It is difficult to identify specific targets for inactivating pathogens during processing.