Constructing an edible extracellular matrix (ECM) scaffold with good thermal stability, self-assembly properties and biocompatibility is crucial for manufacturing structured cell cultured meat products. In this study, carboxymethyl chitosan (CMCS) was introduced into the bovine bone collagen (BBC) system. Using ultraviolet (UV) absorption, infrared (IR) and fluorescence spectroscopy, it was found that the interaction between BBC and CMCS was enhanced with the increase in CMCS concentration, without affecting the triple-helical structure. The results of differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) showed that the introduction of CMCS reinforced the thermal stability of BBC. Turbidity test, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) confirmed an increase in the degree of fibrillogenesis and aggregation behavior and changes in self-assembly rate; a looser and twisted three-dimensional structure with a larger fibril diameter and a wider diameter distribution was observed after the introduction of CMCS. However, the introduction of CMCS did not significantly affect the formation and length of D-periodicity (a characteristic alternating light/dark transverse stripe structure formed during the self-assembly process of collagen fibers) in BBC, and there was no significant difference in the cell compatibility of the system before and after the introduction of CMCS. The BBC-CMCS interaction might be dominated more by electrostatic forces than covalent interactions and hydrogen bonds with the increase in CMCS concentration. These results indicated that the introduction of CMCS improved the thermal stability and self-assembly properties of BBC without affecting its biocompatibility or triple-helical integrity. This study provides a reference for the development of excellent edible collagen-based ECM as a biomimetic scaffold for cultured meat and for the deep processing and high-value utilization of livestock and poultry bone by-products.

This study aims to investigate the influence of the carboxyl substituent groups and the carbon chain length of acrylic acid of ferulic acid (FA) on its bitterness inhibitory effect. Molecular dynamics simulations were employed to analyze the conformational differences in the interaction between bitter taste receptors and bitterness inhibitors, including FA and 4-(2, 2, 3-trimethylcyclopentyl) butyric acid, and the bitterness activator Acesulfame K in order to determine the inhibitory structure F4 of FA for bitter taste receptors. Based on the interaction modes of F4, a series of FA derivatives were constructed. The structure-activity relationship of FA as a bitterness inhibitor was explored by electronic tongue. The results revealed that based on the premise that the interaction modes of the ligand and F4 would be consistent, the charge amount of the hydrogen bond acceptor on FA’s carboxyl substituent group was inversely proportional to the intensity of bitterness inhibition. Adjusting the length of FA’s acrylic acid carbon chain to two carbons destabilized the interaction between the ligand and the key residues, resulting in a reduction in the intensity of bitterness inhibition. In contrast, extending the carbon chain length to four carbons enhanced the bitterness inhibitory intensity. As a new bitterness inhibitor, FA has the potential for development to improve food quality.

In this study, Staphylococcus, Candida and Penicillium that had been isolated and purified from commercial salmon, chicken breast and citrus in our laboratory were used as target microorganisms to explore the sterilization effect and mechanism of applying negative ions in the 4 ℃ cold storage room of a refrigerator. The results showed that negative ion treatment was effective in killing Staphylococcus, Candida and Penicillium in the cold storage room, and this effect increased with sterilization time (when the sterilization time was extended from 0.5 to 2 h, the sterilization efficiency of negative ions on Staphylococcus increased from 92.61% to 99.29%, and the sterilization efficiency on Candida from 61.45% to 98.26%; when the sterilization time was 1 h, the colony growth of Penicillium could be completely inhibited). Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observation showed that negative ion treatment disrupted the structure of Staphylococcus, Candida and Penicillium cells, resulting in leakage of intracellular contents. After this treatment, the conductivity and absorbance values at 260 and 280 nm of the suspensions of Staphylococcus, Candida and Penicillium increased significantly, indicating that their cell integrity was damaged, resulting in leakage of intracellular nucleic acids and proteins. Fluorescein diacetate (FDA) staining showed that negative ion treatment significantly decreased the cell vitality of Candida and Penicillium. In addition, it completely inhibited the spore germination and germ tube formation of Penicillium. Therefore, negative ion treatment in the cold storage room of a refrigerator can destroy the cell integrity of Staphylococcus, Candida and Penicillium, reduce the cell vitality of Candida and Penicillium, and inhibit the spore germination and germ tube formation of Penicillium, thereby effectively killing these target microorganisms.

Under atmospheric pressure, KOH or HCl solution was added to the butylated hydroxytoluene (BHT) oxidation system to adjust the pH, and the oxidative consumption of BHT was monitored by high performance liquid chromatography (HPLC). To investigate the oxidation properties of BHT under pressurized conditions, the temperature and pressure changes during the oxidation process were monitored using the mini-closed pressure vessel test (MCPVT). The oxidation products of BHT were characterized after crystallization and purification and the possible oxidation pathway was speculated. The results showed that under atmospheric pressure, the degradation rate of BHT was less than 5% when the pH was 4 or 6, indicating good stability. At pH 10, the degradation rate of BHT was up to 59% and the oxidation reaction was rapid. KOH and HCl decreased the initial oxidation temperature of BHT from 133.1 ℃ to 53.0 ℃ and 49.1 ℃ in a pressurized closed container, respectively. 2, 6-Di-tert-butyl-4-hydroperoxy-4-methyl-2, 5-cyclohexanedione and 2, 6-di-tert-butyl-4-methyl-4-(3, 5-di-tert-butyl-4-hydroxyphenyl)-2, 5-cyclohexadien-1-one were produced during the oxidation of BHT in both atmospheric alkaline and pressurized environments. The experimental results suggested that BHT was susceptible to oxidative degradation in alkaline and pressurized environments, producing toxic products, posing safety risks.

In order to improve the phenomenon that frozen cooked noodles are susceptible to the formation of ice crystals and quality deterioration during storage, the effects of mannosylerythritol lipids (MELs) versus sucrose ester (SE) on the proportion of freezable water, water distribution, quality characteristics, gelatinization characteristics of wheat flour and the secondary structures of proteins in frozen cooked noodles were investigated. The results showed that the addition of 0.30%–1.10% (m/m) MELs could promote the conversion of free water to bound water in frozen cooked noodles, reduce the proportion of freezable water, and increase the binding of water to macromolecules such as protein and starch. Compared with the blank and SE groups, the quality of frozen cooked noodles made with 0.70% MELs was better, and the hardness was (4 335.317 ± 48.047) g, which was 25.36% higher than that of the blank group. The tensile force and tensile distance at break were (11.22 ± 0.15) g and (69.09 ± 1.34) mm, respectively. The water absorption rate increased significantly, and the cooking loss rate was the smallest, suggesting MELs to be more effective in improving the cooking quality of noodles than SE. At the same time, MELs could effectively delay the retrogradation rate of wheat flour starch, increase the proportions of the secondary structure fractions β-sheet and α-helix, and strengthen the gluten network structure.

In this experiment, egg white protein microparticles (EWPM) were used as a lipid substitute matrix to investigate the effects of EWPM/xanthan gum (XG) blend concentration, pH, sodium chloride concentration, sugar concentration, and homogenization conditions on the rheological properties of ultra-low-fat salad dressing products. The results showed that XG had a significant thickening effect on EWPM-based ultra-low-fat salad dressing. However, excess XG led to a decrease in the resilience of low-fat salad dressing. The effects of basic seasoning components on the quality of ultra-low-fat salad dressing were significantly different. pH and salt concentration had a significant impact on the viscosity of the salad dressing system, while sugar addition had a relatively smaller impact on the viscosity. Moderate colloid mill homogenization speed and time reduced the particle size of the product, thereby increasing the internal uniformity and significantly improving the viscosity of ultra-low-fat salad dressing. This study provides a clearer direction for the optimization of low-fat salad dressing.

This study elucidated the effects of sucrose degradation products, 2-furaldehyde (2-F) and 5-hydroxymethylfurfural (5-HMF), on the stability and antioxidant activity of anthocyanins under different processing and storage conditions. The results showed that during processing, controlling the temperature not more than 85 ℃ and the pH at 3.0 provided the best protection and highest retention rate for anthocyanins, as well as the strongest antioxidant activity. In addition, when the concentration of malic acid was below 0.1 mol/L and the mass fraction of VC was in the range of 0.05%–0.5%, the stability of anthocyanins was obviously disrupted. Dark storage reduced the generation of 2-F and 5-HMF, which in turn improved the stability of anthocyanins. These results provide a reference and technical guidance for the preparation and storage of anthocyanin products containing sucrose in the future, and are of great significance for maintaining the stability of anthocyanins during processing.

Objective: To study the application of Lipozyme RM IM in the synthesis of human milk fat substitutes and its structural changes during recycling. Methods: Using sn-2 high palmitate triglyceride and free fatty acid as the substrates, human milk fat substitutes mainly consisting of 1, 3-dioleoyl-2-palmitoylglycerol (OPO) and 1-dioleoyl-2-palmitoyl-3-linoleoylglycerol (OPL) were synthesized synchronously under the catalysis of Lipozyme RM IM. The amounts of OPO and OPL, oleic acid, linoleic acid, total palmitic acid and sn-2 palmitic acid as evaluated against the Chinese breast milk lipid database, and the activity, secondary structure and endogenous fluorescence intensity of the lipase were investigated as a function of the number of cycles of enzyme recycling. Results: At the first cycle of recycling, the relative contents of OPO and OPL in human milk fat substitutes were 19.41% and 17.04%, respectively. The relative contents of oleic and linoleic acid in the total fatty acids were 35.63% and 22.30%, respectively. The relative contents of total palmitic acid and sn-2 palmitic acid were 28.80% and 52.40%, respectively. When Lipozyme RM IM was recycled for the 17th time, the relative contents of OPO and OPL in human milk fat substitutes were 8.50% and 7.62%, respectively. The relative contents of oleic and linoleic acid in the total fatty acids were 28.62% and 13.38%, respectively. The relative contents of total palmitic acid and sn-2 palmitic acid were 38.26% and 58.40%, respectively. All of them fell within the range of breast milk lipids in China. However, the lipid composition of the enzymatically synthesized product was far from the range. Conclusion: Lipozyme RM IM, with excellent transesterification ability, could be repeatedly used up to 17 times in the synthesis of human milk fat substitutes in this study, proving good recycling properties. This study provides a reference for the extensive application of lipase in synthesis of human milk fat substitutes and the recycling of lipase in the synthesis of human milk fat substitutes in a continuous reactor.

In order to develop and utilize Lentinus edodes protein, the effect of glutamine transaminase (TGase) cross-linking on the physicochemical and processing characteristics of L. edodes protein was studied. The results showed that the addition of 0%–20% TGase gradually reduced the contents of total thiol, free thiol and β-sheet of L. edodes protein, while the fluorescence intensity, particle size, β-turn content and surface hydrophobicity showed a trend of initially increasing and then decreasing. As the shear rate increased, the shear stress of the protein increased and the apparent viscosity decreased, indicating that TGase cross-linking promoted the generation of macromolecular polymers. In addition, the cross-linked protein exhibited a dense texture similar to that of the original protein, indicating the formation of a stable three-dimensional network structure. As the addition level of TGase increased from 4% to 12%, the protein network structure became increasingly dense. Moreover, an appropriate amount of TGase significantly improved the solubility, emulsifying properties, thermal stability, and oil-holding capacity of L. edodes protein. These results indicate that TGase cross-linking improves the physicochemical and processing properties of L. edodes protein to varying degrees.

The aim of this study was to obtain excellent probiotic bacteria from traditional Chinese fermented meat products. A total of 62 bacterial strains from the Miao, Dong and Buyi ethnic groups’ traditional fermented sour meat in selected regions of Guizhou, China were isolated, identified and evaluated for their probiotic potential. Twelve strains with good tolerance to simulated gastric juice were identified, including one strain of Companilactobacillus farciminis, five strains of Lactiplantibacillus plantarum, three strains of Staphylococcus saprophyticus and three strains of S. casei. Among them, C. farciminis KLMM196, L. plantarum KLMM198, S. saprophyticus KLMM253, S. casei KLMM307 and S. casei KLMM313 exhibited good gastrointestinal tolerance, hydrophobicity, self-aggregation ability, strong probiotic potential, and no hemolytic activity.

The microrheological characteristics and stability of set yogurt made from camel and cow milks during fermentation were analyzed by multi-frequency diffusion wave spectroscopy and multi-light scattering spectroscopy, respectively, and their titratable acidity, viable bacterial count, viscosity, water-holding capacity and texture indexes were determined. The results showed that it took 9.5 h for camel milk and 6.5 h for cow milk to reach the end point of fermentation. The results of microrheological analysis showed that as a fluid with low viscoelasticity, fermented camel milk had lower elasticity index (EI) and macroscopic viscosity index (MVI) but higher flow factor (FF) and solid-liquid balance (SLB) values than fermented cow milk. The results of multiple light scattering spectroscopy showed that fermented cow milk was more stable than fermented camel milk during fermentation, while the opposite was true during storage, indicating that the internal structure of fermented camel milk, with higher stability, was more compact. During storage, the titratable acidity of fermented camel milk was lower than that of fermented cow milk, and the numbers of viable bacteria in both of them were more than 1 × 107 CFU/mL, a significant difference being observed between them (P < 0.05), and the water-holding capacity of fermented camel milk was higher than that of fermented cow milk. Texture analysis showed that the hardness, consistency and viscosity index of fermented cow milk were all significantly higher than those of fermented camel milk (P < 0.05). In summary, it is not easy for camel milk to form a gel structure after fermentation, but because of the tight internal structure, fermented camel milk is stable, which is more favorable for product storage. In contrast, it is easier for cow milk to form a thick and dense texture after fermentation. This study provides a theoretical basis for the practical application and promotion of fermented camel milk, and provides ideas for the diversified development of fermented non-bovine milks.

In this study, the total flavonoid composition and bioactivity of finger millet was analyzed. Eleusine coracana flavonoids (ECFs) were obtained through sequential 70% ethanol extraction, ethyl acetate extraction, and purification with D101 macroporous resin. The total flavonoid content was determined using the NaNO2-Al(NO3)3-NaOH colorimetric method, and the flavonoid composition using ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The in vitro antioxidant activity of ECFs was evaluated using chemical assays, and the anti-aging activity using C. elegans as a model organism. The results demonstrated that the total flavonoid content of ECFs was 82.6%, with 16 major components being identified, including flavonoid glycosides and catechin. In vitro antioxidant tests showed that ECFs exhibited half-maximal inhibitory concentrations (IC50) of 45.34 and 22.75 μg/mL against 1, 1-diphenyl-2-picrylhydrazyl (DPPH) and 2, 2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) cation radicals, respectively, with the IC50 against ABTS cation radicals being lower than that of the positive control vitamin E (29.25 μg/mL). At a concentration of 200 μg/mL, ECFs increased catalase activity in C. elegans by 53.98%, superoxide dismutase activity by 30.64%, and glutathione levels by 51.06%, while decreasing malondialdehyde (MDA) content by 11.82%. ECFs extended the lifespan of C. elegans by 17.86%, and improved its mobility compared to the control group, indicating improved vitality. ECFs had no significant effect on C. elegans fecundity suggesting no promoting effect on its reproductive function. Additionally, ECFs reduced the level of lipofuscin by 53.91%. These findings demonstrated that ECFs had significant antioxidant effects both in vitro and in vivo as well as remarkable anti-aging activity in C. elegans, which could provide a foundation for the functional application of finger millet.

In this study, the effect of 18 weeks of dietary supplementation of porcine submaxillary gland mucin (PSM) as an abundant source of N-hydroxyacetylneuraminic acid (Neu5Gc) on the expression of proteins involved in the nuclear factor kappa-B (NF-κB) signaling pathway in the liver, serum interleukin (IL)-6, IL-1β, tumor necrosis factor-alpha (TNF-α), serum amyloid A protein (SAA) and the gut microbiota in cytidine-5’-monophosphate-N-acetylneuraminic acid knockout (Cmah-/-) mice was investigated. Meanwhile, the effect of gender on Neu5Gc-induced inflammation in Cmah-/- mice was analyzed. The results showed that Neu5Gc activated the NF-κB signaling pathway and significantly increased the serum concentration of IL-6, IL-1β, TNF-α and SAA in both male and female mice when compared with normal controls. In the PSM-treated male mice, the ratio of Bacteroidetes to Firmicutes (B/F) significantly increased, the relative abundance of Muribaculaceae and Prevotellaceae significantly decreased, and the relative abundance of Clostridia UCG-014 and Prevotellaceae_NK3B31_group, which are positively associated with intestinal inflammation, significantly increased. In the PSM-treated female mice, the richness of gut microbiota significantly decreased, and so did the relative abundance of Lachnospiraceae and Oscillospiraceae. In conclusion, Neu5Gc in PSM could promote inflammatory responses in Cmah-/- mice through significantly down-regulating the abundance of relevant bacterial communities, facilitating the growth of bacterial communities positively associated with intestinal inflammation, leading to structural disorders of gut microbiota, activating the NF-κB signaling pathway and increasing the secretion of serum inflammatory cytokines, and inflammatory response induced in mice by Neu5Gc was affected by gender. Our study provides a reference for a healthy diet.

In this study, Lactobacillus paracasei FP02, a strain isolated from pickled Chinese cabbage, was tested for its capability to reduce uric acid in vitro, and its physiological and biochemical characteristics were characterized. Furthermore, the effect of this strain on the serum uric acid level of a hyperuricemic (HUA) rat model was explored. The in vitro results showed that L. paracasei FP02 degraded uric acid and its precursor substances, inosine and guanosine, by 29.10%, 67.09%, and 70.48%, respectively, and inhibited xanthine oxidase (XOD) activity by 64.20%. Simultaneously, this strain could ferment various sugars (alcohols) and exhibited good tolerance to gastric acid and bile salts. The 14-day continuous intragastric administration of freeze-dried L. paracasei FP02 powder reduced the serum uric acid concentration by 49.96% compared to the hyperuricemia model group (P < 0.001), which was established by intragastric administration of potassium oxonate combined with high dietary uric acid. After the treatment, the serum uric acid concentration approached the levels observed in the blank control group. Additionally, in the FP02 treatment group, uric acid excretion in the urine increased, and serum XOD activity was significantly inhibited (P < 0.001). Renal sections showed that renal injury was partially restored in the FP02 treatment group. This study will lay the foundation for the development of L. paracasei FP02 as a potential drug or functional food for preventing HUA.

In order to study the aroma-active components of pungent spices and to promote the standardization of their processing and application, this work used solvent-assisted flavor evaporation (SAFE) combined with gas chromatography-mass spectrometry/olfactometry (GC-MS/O) to qualitatively and quantitatively analyze the aroma-active components of 20 pungent spices. Using olfactory analysis, a total of 203 aroma-active compounds with flavor dilution (FD) values ≥ 9 were identified mainly consisting of alcohols, sulfur compounds, olefins, esters, ketones, aldehydes, phenols and acids, and the concentrations of aroma-active compounds varied between different spices. Principal component analysis (PCA) showed that all samples could be well classified into three groups. The aroma-active compounds of garlic, Welsh onion, chive and onion were dominated by sulfur compounds, while the aroma-active components of the other pungent spices were dominated by olefins, alcohols, phenols and ketones. Aroma-active sulfur-containing compounds were detected in garlic at the highest level of 3 484 777.68 μg/kg, including disulphide and trisulphide, contributing to the characteristic flavor of Allium plants. The highest content of aroma-active olefinic compounds of 72 847 224.14 μg/kg was detected in ginger, and the major aroma-active components of ginger were α-gingerene and β-sesquiterpene. Alcohols and ketones were detected in wild mint at high levels of 284 886.09 and 196 167.66 μg/kg, respectively, and the characteristic aroma components of wild mint were menthol and carvone. Aroma-active aldehydes were detected in litsea at high levels of 469 242.68 μg/kg. The major aroma-active components detected in litsea were citral and citronellal. This study provides a theoretical basis for the deep processing of pungent spices.

The metabolomic differences between the peels of Citrus reticulata ‘Chachi’ and different varieties of Citrus unshiu Marc. were analyzed to provide a theoretical basis and scientific evidence for the development and utilization of the peels of Citrus unshiu Marc.. The chemical composition of Citrus reticulata ‘Chachi’ (CZG) and three different varieties of Citrus unshiu Marc. (‘Youliang’ (YL), ‘Nangan 20’ (NG) and ‘Gongchuan’ (GC)) were determined by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), and the metabolomic data were comparatively analyzed using principal component analysis (PCA), orthogonal partial least square-discriminant analysis (OPLS-DA) and cluster analysis (CA) to screen differential metabolites. Through database comparison, 790, 796 and 818 metabolites were identified between CZG and YL, NG and GC, respectively, with organic oxides, flavonoids, carboxylic acids and their derivatives accounting for the highest proportions, which are mainly involved in the metabolic pathways of flavonoid and flavanol biosynthesis, isoflavones biosynthesis, α-linolenic acid metabolism, and phenylpropanoid biosynthesis. Using the cutoff of variable importance in the projection (VIP) score > 1 with P value < 0.05, stable and reliable differential metabolites were selected. A total of 43 differential metabolites of 11 classes were identified between Citrus reticulata ‘Chachi’ and Citrus unshiu Marc., the predominant ones being flavonoids, amino acids and purine nucleosides. Most flavonoids in Citrus unshiu Marc. such as 5, 6, 7, 8, 3’, 4’, 5’-heptamethoxyflavone, quercetin, naringenin, and naringenin were up-regulated, which could be used as potential markers to differentiate Citrus reticulata ‘Chachi’ from Citrus unshiu Marc.. Furthermore, Citrus unshiu Marc. had a higher content of flavonoids and therefore could be used as a source of Citri Reticulatae Pericarpium.

This study processed Jingxi rice 7233 into reasonably well milled (RWM, bran degree 2.8%, 4.9%) and well milled (WM, bran degree 1.4%) grades, and compared the processing characteristics, physicochemical properties, fatty acid composition, volatile composition and taste quality between the two grades. The results showed that the average rice yield and head rice yield of RWM were 1.3% and 1.8% higher than those of WM, respectively. The contents of total phenolic acids, water-soluble protein, unsaturated fatty acids, especially polyunsaturated fatty acids, in RWM rice were more than 1.5 times as high as those in RWM rice. The color difference between RWM and WM rice was greater than 2.0, which could be perceived with the naked eye. Totally 62 characteristic peaks were marked by gas chromatography-ion mobility spectrometry (GC-IMS), and 38 compounds were accurately identified. The contents of 58% of volatile components were significantly higher in RWM rice than in WM rice. The cooking time of RWM rice was significantly longer than that of WM rice, and the breakdown viscosity of starch and stickiness were significantly lower than those of WM rice. RWM rice has great advantages in paddy utilization rate, nutrition and health, but further research and optimization are needed in terms of appearance, smell and taste quality.

This study analyzed and compared the effects of different drying methods on the volatile composition and aroma characteristics of Osmanthus fragrans extract and absolute oil. The volatile composition was determined by gas chromatography-mass spectrometry (GC-MS) and partial least squares-discriminant analysis (PLS-DA), relative odor activity value (ROAV), aroma profile radar and principal component analysis (PCA) were employed to determine the effect of different drying methods on the volatile aroma components of O. fragrans extract and absolute oil. The results showed that a total of 113 volatile components were identified. The types and concentrations of volatile components were significantly different among samples (P < 0.05). Through PLS-DA analysis, 36 volatile marker substances were selected using the cut-off of variable importance in the projection (VIP) score greater than 1, and the accuracy of predictive discrimination of O. fragrans extract and absolute oil prepared by different drying methods was 99.6%. The ROAV and aroma radar plots showed that dihydro-β-ionone, linalool, nonanal, β-ionone, and dihydro-β-iononeone contributed significantly to the aroma of O. fragrans extract and absolute oil, being responsible for the floral, woody, and fruity aromas. Notably, the extract from freeze-dried O. fragrans exhibited a more intense aroma. PCA analysis indicated that freeze-drying contributed to improving the aroma quality of O. fragrans extract and absolute oil. The results of this study provide theoretical support for process optimization and quality improvement of O. fragrans extract products.

In this study, the effects of different curing methods (static treatment, ultrasonic treatment, ultrasonic treatment combined with tumbling, vacuum tumbling and atmospheric pressure tumbling) on the textural properties, water retention and flavor quality of low-salt pre-prepared sea bass were investigated using texture analysis, scanning electron microscopy (SEM), liquid chromatography (LC) and gas chromatography-mass spectrometry (GC-MS). The results showed that tumbling alone and combined with ultrasonic treatment both significantly increased the marinade absorption rate and the mass transfer rate of sodium ion (P < 0.05), and the marinade absorption rate was 15.07% in the atmospheric pressure tumbling group, which was accompanied by reduced hardness and chewiness of fish meat. Organoleptic analysis showed that the fish treated by ultrasonic-assisted tumbling and tumbling was soft in texture, uniformly salty, and had less odor. In addition, both tumbling treatments significantly increased the total free amino acid content (P < 0.05), and the total free amino acid content was 7.395 mg/g in the atmospheric pressure tumbling group, which was about 1.24 times higher than that of the static treatment. A total of 65 volatile flavor compounds were detected across all treatment groups, among which, the contents of alcohols, esters and aromatic compounds were significantly higher (P < 0.05) in the tumbling treatment and ultrasonic-assisted tumbling groups than in the other treatment groups, suggesting that tumbling, irrespective of whether combined with ultrasonic or not, contributed to the formation of flavor substances. However, single tumbling marination showed poor water retention and water-holding capacity, and excessive tumbling might have adverse effects on fish texture. Therefore, ultrasonic-assisted tumbling was more suitable for the intensive processing of sea bass.

With a view to investigating the effect of wheat sprouting degree on the cooking quality, textural characteristics and sensory evaluation of dried whole wheat noodles, whole wheat flours with different degrees of wheat sprouting (bulging, revealing, sprout length equal to 1/4, 1/2, 3/4 the grain length, and the grain length) were used to prepare dried whole wheat noodles. The results showed that the surface brightness of whole wheat noodles first increased and then decreased with the increase in wheat sprouting degree. The moisture absorption rate of dry matter reached the maximum when the sprout length was 1/2 the grain length, and the dry matter loss rate reached the minimum at the revealing stage. The viscosity and adhesion capacity of whole wheat noodles reached the minimum when the sprout length was 1/2 the grain length, and the hardness and shear work reached the maximum when the sprout length was 1/4 the grain length, and the breaking strength, tensile strength, elasticity and sensory score were the maximum when the sprout length was 1/2 the grain length. Overall, the eating quality of dried whole wheat noodles prepared from whole wheat flour at the stage of wheat revealing to sprout length equal to 1/2 the grain length was the best, and the overall eating quality of noodles prepared from sprouted whole wheat flour was improved compared with that of the control prepared from un-sprouted whole wheat flour.

In order to investigate and evaluate the processibility of broccoli by-products (stems and leaves) and hence to provide a reference for their rational utilization, this study investigated the physicochemical properties and nutritional quality of broccoli stem and leaf powders prepared by different drying methods, namely vacuum freeze drying (FD), microwave freeze drying (MFD), heat pump drying (HPD) and hot air drying (HAD). The results showed that the color difference ΔE between MFD-treated and fresh broccoli stems was 8.52 ± 0.02, which was smaller than that between HAD-treated and fresh samples (30.27 ± 0.28), indicating that MFD had better color preservation effect. The median particle size ranges of broccoli stem and leaf powders were 31.19–52.09 and 32.30–40.47 μm, respectively. Broccoli leaf powder had lower water and oil retention capacities but higher swelling force than that broccoli stem powder. The water retention capacity of FD-dried broccoli stem powder was (11.40 ± 0.46) g/g, and the oil retention capacity of MFD-dried broccoli stem powder was (1.40 ± 0.04) g/g. FD and MFD could effectively maintain the microstructure of broccoli stems and leaves, with obvious pores. The specific energy consumption of FD and MFD for treating an equal amount of broccoli stems was 7.35 and 3.26 kW·h/kg, respectively, so MFD reduced energy consumption by 55.65% when compared with FD. MFD maintained heat-sensitive and readily oxidized nutrients well, resulting in good antioxidant activity. The 1, 1-diphenyl-2-picryl hydrazine (DPPH) scavenging capacity, 2, 2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) cationic radical scavenging capacity and ferric ion reducing antioxidant power (FRAP) of MFD broccoli leaf extract at a concentration of 0.125 mg/100 mL were 70.21%, 71.11% and (0.31 ± 0.01) mmol/g, respectively. In summary, broccoli stem and leaf powders had good physicochemical properties and nutritional quality and therefore could be used as raw materials for developing functional foods. The application of drying technology enables the rational utilization of broccoli stems and leaves.

The adsorption characteristics of functionalized polystyrene resin for acetaldehyde and furfural in Baijiu were evaluated in comparison with those of other sorbents including activated carbon, diatomite, and AB-8 macroporous resin. The adsorption capacity of the modified polystyrene resin was 60.19 and 47.37 mg/g for acetaldehyde and furfural at 240 min and 323 K, respectively, greatly exceeding that of the other sorbents. Adsorption experiments were conducted on three major commercial flavor types of Baijiu, revealing less than 1% change in the total ester content of Baijiu before and after adsorption, so selective adsorption could be achieved using this sorbent. Its structure was characterized through elemental analysis (EA), Fourier transform infrared spectroscopy (FTIR), Brunauer-Emmett-Teller (BET) surface area and pore structure analysis, thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The adsorption mechanism of aldehydes and furfural on the functionalized resin was investigated using adsorption kinetics, isotherms, and thermodynamics. The findings indicated that the adsorption process fitted well with the pseudo-second-order model and the Freundlich model. Based on the results of ΔG0 > 0, ΔH0 > 0, and ΔS > 0, the adsorption was a non-spontaneous endothermic process. As the adsorption process proceeded, the solution became less orderly, and the adsorption process was primarily governed by chemisorption. This research serves as a reference for the quality and health improvement of Baijiu.

Heat-moisture treatment (HMT) was evaluated for its effects on the antioxidant, nutritional and dough properties of different legume flours. The results showed that the contents of total phenols and flavonoids and the antioxidant capacity of adzuki bean and pea flour initially increased and then decreased with the increase in HMT time, reaching the maximum at 0.5 and 1.0 h, respectively; whereas the contents of total phenols and flavonoids of white kidney bean flour increased with HMT time up to 8.0 h. HMT had consistent effects on the scavenging activity against 2, 2’-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) cation radical and 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical and the contents of total phenols and total flavonoids. The major fatty acids in all three legume flours were palmitic acid, stearic acid, linoleic acid, cis-11-eicosatetraenoic acid and oleic acid. HMT for 2.0 h and longer had a significant effect on the contents of oleic acid, linoleic acid and cis-11-eicosatetraenoic acid in white kidney bean flour. After HMT, the contents of free amino acids in red and white kidney bean flour decreased significantly due to its involvement in the Maillard reaction, while bound amino acids in pea flour were released, thereby increasing the amount of free amino acids. Scanning electron microscopy (SEM) showed pores in and protein adhesion on the starch granules due to protein denaturation and partial gelatinization of starch with increasing HMT time. The recrystallization of starch resulted in a decrease in peak, trough and setback viscosity, and poorer shear resistance of legume flour. The results of dough water distribution showed that the relaxation times T21 and T22 of adzuki bean flour increased after HMT, and the dough formation of adzuki bean flour was better than that of the other two flours. Thermomechanical analysis showed that HMT enhanced protein weakening in mixed legume-wheat flour doughs and inhibited starch retrogradation, thus improving product quality.

In order to study the color stability and change mechanism of beef during postmortem storage, quantitative proteomic analysis was carried out on bovine Longissimus dorsi with high and low color stability at 75 min, 2 days and 8 days after slaughter. Proteomic results showed that a total of 1 377 proteins were identified in the high and low color stability groups, including 136 differential proteins. Bioinformatics analysis found that the differential proteins were mainly involved in postmortem biochemical processes such as redox, glucose metabolism, signal transduction and apoptosis, which were closely related to the regulation of meat color stability during postmortem storage. By functional analysis of these differential proteins, four key differential proteins related to the respiratory electron transport chain were selected, namely, cytochrome complex subunit (UQCR10), cytochrome C oxidase subunit VIIa peptide 1 (COX7A1), mitochondrial ATP synthase subunit (ATP5MG), and mitochondrial ATP synthase subunit (ATP5MF). These proteins participated in the postmortem energy metabolism and redox processes and affected oxidoreductase activity, which in turn affected the color stability of beef during storage. This study provides an idea for the regulation of meat color stability in the future.

In order to explore the effects of melatonin (MT) treatment on cold resistance in apricot fruits, Xinjiang-grown ‘Saimaiti’ apricot fruits were treated with MT or distilled water as a control at 0.05 MPa for 2 min followed by atmospheric pressure for 8 min. During 49 days of storage at (0 ± 0.5) ℃ and relative humidity of 90%–95%, chilling injury index, incidence of chilling injury, cell membrane permeability, malondialdehyde (MDA) content, superoxide anion (O2-·) production rate, hydrogen peroxide (H2O2) content, antioxidant content, energy substance content and related enzyme activity were measured every 7 days, and mitochondrial structure was observed by transmission electron microscopy (TEM). The results showed that MT treatment effectively inhibited the increase of cell membrane permeability and the accumulation of MDA during storage, significantly reduced the incidence and index of chilling injury, and delayed the occurrence of chilling injury symptoms. In addition, compared with the control group, MT treatment enhanced the activities of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), aseorbate peroxidase (APX) and glutathione reductase (GR), inhibited the increase of O2-· production rate and the accumulation of H2O2, increased glutathione (GSH) content, delayed the decrease of ascorbic acid (ASA) content, and effectively maintained the balance of intracellular ROS. MT treatment could also effectively delay the decrease of succinic dehydrogenase (SDH), cytochrome c oxidase (CCO) and H+-ATPase and Ca2+-ATPase during storage, maintain high levels of adenosine triphosphate (ATP), adenosine diphosphate (ADP) and energy state, and preserve the integrity of mitochondrial structure and function. In conclusion, MT treatment could enhance the cold resistance of apricot fruits by regulating the energy metabolism and antioxidant capacity. This provides a new theoretical basis for chilling injury control of apricot fruits.

PVA/MPA-InP/ZnS QD fluorescent film for rapid detection of trace Cu2+ was developed using 3-mercaptopropionic acid (MPA)-capped InP/ZnS quantum dots (MPA-InP/ZnS QDs) as the fluorescence-sensitive material and polyvinyl alcohol (PVA) as the substrate. The microstructure, optical properties and mechanical properties of the fluorescent film were characterized. The results showed that PVA interacted with MPA-InP/ZnS QDs through hydrogen bonds. The fluorescence intensity of the film was significantly correlated with Cu2+ concentration in the range of 0–1 000 nmol/L (R2 = 0.95). The limit of detection (LOD) for Cu2+ was 23 nmol/L, and the response time was 6 minutes. Finally, the film was applied to the detection of trace Cu2+ in drinking water, beverages and alcoholic drinks with the advantages of high selectivity, rapid response and good portability, which exhibited a broad application prospect.

An inductively coupled plasma triple quadrupole mass spectrometric (ICP-QQQ-MS) method was established for the determination of cadmium (Cd) in cereal-based complementary foods for infants and young children. In different collision/reaction modes, namely single quadrupole-helium collision (SQ-He), double quadrupole-helium collision (QQQ-He) and double quadrupole-oxygen reaction (QQQ-O2), various possible interferences in the MS measurement process were analyzed and several methods to eliminate them were proposed. The results showed that the decreasing order of the ability to resist matrix, oxide and multiatomic ion interferences was QQQ-O2 > QQQ-He > SQ-He. QQQ-O2 combined with the standard addition method showed a better ability to eliminate interference. By introducing interference correction equations, the problem of inconsistency between Cd isotope abundance ratio and natural abundance ratio caused by interference from stannum (Sn) isotopes was effectively solved. The results of Cd determination by isotope dilution mass spectrometry (IDMS) in the QQQ-O2 mode were consistent with those obtained using the standard addition method, indicating effective elimination of both matrix effect and MS interference. The proposed ICP-QQQ-MS method allows the accuracy determination of Cd in complex matrix samples.

In this study, the dissipation and transformation of acetamiprid were investigated during the cowpea pickling process and the toxicity assessment software Ecological Structure Activity Relationship (ECOSAR) and the Toxicity Estimation Software Tool (T.E.S.T.) were used to predict the toxicity of acetamiprid and its transformation products (TPs). The results showed that acetamiprid was rapidly degraded during the pickling process with a degradation rate constant of 0.967 61 and a half-life of (34.95 ± 0.78) d. Four TPs from acetamiprid were found during cowpea pickling process. Among them, the oral lethal doses of TP1 and TP2 in rats were 358.17 and 385.7 mg/kg, respectively, which belonged to the “hazardous” category, and the developmental toxicity of TP1 and TP2 was significantly increased compared with that of acetamiprid. In addition, acetamiprid, TP1, TP2, and TP3 were detected in all real samples. The highest mass concentration of acetamiprid was 473.8 μg/L and the median concentration was 41.1 μg/L. These results reveal the degradation and biotransformation of acetamidine during pickling of cowpea and contribute to a better understanding of the possible health risks of pickling foods.

Objective: To assess the safety of flusilazole and ningnanmycin in citrus and its processed products, field trials were conducted in Chongqing and Hunan and orange juice processing was performed following the commercial procedure. The residue dynamics, processing factors and dietary risk assessment of flusilazole and ningnanmycin during orange juice processing were investigated. Methods: The quick, easy, cheap, effective, rugged, and safe (QuEChERS) procedure and solid phase extraction (SPE) were employed to develop a quantitative analytical method for flusilazole and ningnanmycin in orange and its processed products using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), respectively. Results: The sensitivity and accuracy of the established method were good. In orange peel essential oil at 0.05, 0.5, 2 and 20 mg/kg, the average recoveries of flusilazole were 78.5%–108.4% with relative standard deviation (RSD) between 0.5% and 6.6% at spiked levels of 0.01, 0.1 and 0.2 mg/kg. In orange peel essential oil at 0.05, 0.5, 5 and 20 mg/kg, the average recoveries of ningnanmycin were 88.3%–105.6% with RSD between 0.3% and 8.7% at spiked levels of 0.05, 0.5 and 5 mg/kg. The squeezing process was a highly effective way to reduce the residues of flusilazole and ningnanmycin, which were reduced by 93.3% to 98.6% in mother juice, respectively. Both compounds were prone to enrichment in orange pomace. The residue level of ningnanmycin in the peel essential oil was reduced while that of flusilazole was enriched. Processing factors less than 1 were observed for the other processed products. The risks of acute and chronic dietary exposure to flusilazole and ningnanmycin among different age groups were both lower than 100%, which were at an acceptable level. Conclusion: This study could provide a reference for residue behavior and dietary exposure risk assessment of flusilazole and ningnanmycin in citrus and its products, thereby promoting the scientific application of the two pesticides for disease prevention in the citrus industry.

With the popularization of the concept of a healthy diet, people are increasingly concerned about food safety. Thermal processing provides foods with desired smell, unique flavor and taste, but also leads to the generation of harmful substances, such as polycyclic aromatic hydrocarbons (PAHs), which are a class of substances with acute toxicity, genotoxicity, carcinogenicity and phototoxicity that exist widely in thermally processed food matrices. Studies have shown that dietary exposure to PAHs accounts for 88%–98% of the total daily exposure of humans to PAHs. Thus, controlling PAHs levels in foods is of great practical importance for reducing the harmful effects brought about by dietary exposure to PAHs. This paper reviews the major generation pathways, deleterious effects and control strategies of PAHs, with a view to providing a reference for research on new control technologies for PAHs in foods.

Ice preservation is one of the most extensive methods of food preservation, and improving the ability of ice preservation is a key and difficult problem in the field of food preservation. However, the limited ability of traditional ice to inhibit microbial viability hinders the further development of the food industry. At present, new functional ices such as electrolyzed water ice, ozone ice, plasma activated water ice, bacteriostatic substance added ice, fluidized ice, ultraviolet radiation ice and composite functional ice, which have better preservation effect than traditional ice and therefore have broad prospects for development and application, have found wide applications in the field of food preservation. Research on new functional ice with better sterilization and preservation effect has become a hot spot in the food industry. Therefore, this paper summarizes the preparation, sterilization and preservation mechanism of new functional ice in order to provide a theoretical basis and scientific evidence for further development of new functional ice and to promote the application of new functional ice in food sterilization and preservation.

Salmonella is an important cause of foodborne diseases worldwide, with a high detection rate in fresh meat. Rapid, accurate and sensitive detection of Salmonella is crucial in safeguarding food safety and people’s health. Electrochemical aptamer-based sensors, integrating the advantages of both aptamers and electrochemical sensors in terms of recognition specificity and sensitivity, attract much attention, thus having the potential for application in qualitative and quantitative detection of Salmonella. However, most existing reviews focus on the preparation process of sensors, while little information is available regarding the correlation between the structure and properties of Salmonella, leading to the lack of a direct theoretical basis for the design and improvement of sensors. Therefore, based on the structure and properties of Salmonella, this article establishes its internal connection with aptamer-based sensors, and summarizes the electrode modification materials, aptamer fixation on the working electrode, the signal sensing strategies and the signal amplification strategies, in order to provide a reference for the rapid detection of Salmonella and other foodborne pathogenic bacteria.

Cross-contamination of foodborne pathogenic bacteria is a widespread phenomenon in food processing and production, storage and transportation, and household consumption. It is regarded as one of the important causes of foodborne disease outbreaks. Using mathematical models to simulate the transfer of foodborne pathogenic bacteria in different food media enhances our understanding of the pattern of transmission of the pathogens through cross-contamination. Determining the key links in the microbial cross-contamination by combined use of cross-contamination modelling with microbiological risk assessment and designing novel antimicrobial coatings will effectively prevent and control the occurrence of microbial cross-contamination. Therefore, this article reviews the food safety problems caused by cross-contamination of pathogenic bacteria in the food industry and household settings, and provides a detailed overview of the latest progress in mathematical modelling of cross-contamination of foodborne pathogenic bacteria, and describes the application of microbial risk assessment combined with hazard analysis and critical control point (MRA-HACCP) and antimicrobial coatings in the prevention and control of cross-contamination of foodborne pathogenic bacteria from the perspectives of both global control and source control. It concludes with an outlook on future research and control strategies for foodborne pathogen cross-contamination.

The taste of fruits is an important attribute of fruit quality. The taste substances in fruits stimulate the taste buds to produce taste sensations, which are transmitted through the gustatory nerves into the neural center, finally entering the cerebral cortex. The major taste substances in fruits are soluble sugars, organic acids, polyphenols, alkaloids, and other bitter substances. These taste substances altogether contribute to the unique taste of fruits. Taste regulation of fruit products such as canned fruits, dried fruit products, liquid fruit products, jams and preserved fruits has received increasing attention, and there are a growing number of studies on methods for the regulation of fruit product taste. Many methods including electronic tongue technology, molecular sensory science, and quantitative descriptive analysis have been applied for studying the taste of fruits. This article provides an overview of taste substances in fruits and fruit products and methods for their taste regulation, and introduces commonly used methods in fruit taste research, aiming to provide theoretical guidance for research in the field of fruit taste.

This study systematically reviewed the Chinese and international laws, regulations and scientific guidelines regarding novel food raw materials. It clarified the basic definition of “novel food raw materials” and related concepts at home and abroad, and elaborated on the changes in the nomenclature and types of novel food raw materials in China. It also gave a brief overview of the categories and scope of novel food raw materials abroad, a general explanation of declaration information and approval management of novel food raw materials, a brief summary of China’s standards for testing novel food raw materials, and a detailed review of various analytical methods for non-microbial novel food raw materials such as liquid chromatography, gas chromatography and mass spectrometry in order to provide reference for the standardization and uniform detection of novel food raw materials in China.

Polyphenols are important secondary metabolites in plants, which have health benefits such as antioxidant, anti-inflammatory and anticancer effects. However, most polyphenols have low bioavailability after entering the gut. Studies have shown that microbial transformation can improve the availability of plant-based foods. In this article, the biotransformation of different phenols by microorganisms during the fermentation of plant-based foods is reviewed, and the changes in the composition and bioactivities of polyphenols before and after fermentation are analyzed, which is of great significance for revealing the mechanism of microbial transformation of polyphenols and for optimizing the application and development of polyphenols.

Cancer is now the second leading cause of death after cardiovascular diseases. Although there are many different cancer treatments available, all of them have serious side effects and drug resistance. Therefore, scientists are searching for natural products that can effectively prevent the occurrence of cancers. Studies have shown that the consumption of citrus fruits can reduce the risk of several diseases, including cancers, and its anti-cancer effects are attributed to a variety of bioactive ingredients. This article systematically summarizes recent progress in research on the major anti-cancer ingredients in citrus fruits and their molecular mechanisms. Citrus is one of the important fruits with high medicinal value. In-depth studies on its anti-cancer effects and molecular mechanisms will help to enhance its industrial value, and provide a theoretical basis for the processing and development of citrus fruits into functional foods for chemical prevention of cancers. As the anti-cancer constituents and mechanisms of citrus fruits have been understood fully, their application as a natural source of anti-cancer agents in clinical cancer treatments can be expected soon.

As a common plant that is widely used for both medicinal and culinary purposes, ginger is rich in polysaccharides, terpenes, phenols and other active substances, imparting it with antioxidant, anti-inflammatory, antibacterial, anticancer, neuroprotective and antidiabetic properties. In this paper, we review the current understanding on the composition and biological activities of ginger extract, discusses the application of ginger in food packaging, and propose future directions for ginger extract research, hoping to arouse people’s attention on ginger and its further application so as to promote the comprehensive utilization of ginger resources.

Polysaccharides are a class of natural macromolecular polymers with complex and large molecular structures, which are closely related to their biological activities. However, traditional analytical methods can only provide limited information on the structures of polysaccharides. Mass spectrometry (MS) is an analytical method that measures the mass-to-charge ratio of molecules allowing for determination of the mass and calculation of the the molecular structure. As a powerful tool for polysaccharide structure analysis, MS can provide rich information, including molecular mass, polymerization degree, monosaccharide composition, glycosidic bond type, the order of arrangement of glycosyl groups, and substituent group sites, which has unique advantages in the characterization of polysaccharide structure. This paper summarizes the general pattern of mass spectral fragmentation of polysaccharides, introduces the principles and characteristics of different types of MS as well as representative applications of MS combined with electron ionization source, fast atom bombardment source, electrospray ionization source, matrix-assisted laser desorption ion source, real-time direct analysis source, ion mobility or tandem mass spectrometry for the structural elucidation of polysaccharides. Furthermore, future prospects for the application of new MS techniques for analyzing the structures of polysaccharides are discussed. The aim of this paper is to summarize the application of MS to provide scientific reference for the basic research work of polysaccharide compounds, such as quality standard, structural characterization, pharmacodynamics, pharmacokinetic, constitutive relationship, and the development and creation of polysaccharide food, health food, and clinical drugs.

China has initially established a legal system regarding food safety risk monitoring and assessment, and has completed the construction of a national food safety risk monitoring network. This legal system belongs to the category of administrative law and has the attributes of administrative law. From the perspective of administrative law, the current risk monitoring and assessment mechanism still has some problems in terms of information sharing, risk early warning and joint law enforcement. In order to better ensure food safety, we should reconstruct the legal system concerning risk monitoring and assessment, strengthen risk awareness, improve procedural settings and the monitoring network, and promote the integration of the food safety risk monitoring and food safety random inspection systems. Scientific and efficient risk monitoring and assessment will identify food safety risks timely, guide the formulation of food safety standards and help regulatory authorities with the hierarchical management of food safety, thus further regulating the order of the Chinese food market and providing people with safe and satisfactory foods.