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To uncover the relationships between lipid components and flavor volatiles, distinctness in lipid components and odor substances in giant salamander livers of different genders were comparatively characterized through UPLC-Q Exactive-MS lipidomics and gas chromatography-ion migration spectrometry (GC-IMS). A total of 2171 and 974 lipid metabolites were detected in positive and negative ion modes, respectively. Triglycerides (TG) and phosphatidylcholines (PC) are the most abundant types of lipids. TG level in male livers was higher than that in female livers (P 0.05). Additionally, a total of 51 volatile components were detected through GC-IMS. Ketones (42.18 % ∼ 45.44 %) and alcohols (24.19 % ∼ 26.50 %) were the predominant categories, and their relative contents were higher in female livers. Finally, 30 differential lipid metabolites and 12 differential odor substances were screened and could be used as distinguishing labels in giant salamander livers of different genders. Correlation analysis indicated that PS(36:2e), TG(48:13), ZyE(37:6), and ZyE(33:6) correlated positively with 3-methyl butanal, 3-hydroxy-2-butanone, and 2-methyl-1-propanol (P

This study aimed to extract sturgeon oil (SO) from the sturgeon head and apply it to sturgeon meat to produce surimi gel. The effects of SO and its Pickering emulsion on the qualities of surimi gel were investigated. The results demonstrated that Pickering emulsions improved the quality deterioration of the gel caused by the direct addition of SO, especially the soy isolate protein (SPI) emulsion and the pea isolate protein (PPI) emulsion. Pickering emulsions contributed to a more uniform and compact network structure of the gel, improved the texture properties, enhanced the freeze-thaw stability, and reduced lipid oxidation. Additionally, compared to the addition of exogenous lipids such as peanut oil and linseed oil, SO and its Pickering emulsion better maintained the characteristic flavor of sturgeon surimi gel. This study provides valuable data and feasible ideas for expanding the utilization of sturgeon by-products and developing new types of surimi gel products.

This study aimed to utilize Enterococcus lactis S-15 for the preparation of fermented shrimp gels. The gel properties and the gelation mechanism of proteins were investigated under acid-induced denaturation and protein degradation, and the quality of the gel was evaluated. Results showed that the pH of the shrimp surimi decreased from 7.35 to 4.74. The optimal gel strength observed at 24 h of fermentation was 326.41 g × cm, and disulfide bonds played a crucial role in the fermented gel. The fermented gel exhibited higher cooking loss rates and freeze-thaw loss rates compared to the heat-induced gel (control). However, fermented gels exhibited high overall acceptability both before and after cooking. The volatile basic nitrogen content in the fermented gel remained below 28.00 mg/100 g, within the safe range, and no histamine was detected. The results provide valuable data for the development and reprocessing of fermented shrimp surimi gel.

To elucidate the relationships between lipid components and odor traits, this study comparatively characterized the distinct lipid compositions and flavor volatiles in giant salamander tails of different sexes via mass-spectrometry-based lipidomics and GC-IMS. A total of 3145 fat metabolites were detected in male and female giant salamander tails, with the largest contributors being triglycerides (TGs, 840) and phosphatidylcholines (PCs, 383). Notably, the contents of PCs and TGs were greater in female tails than in male tails, and the levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were also greater in the female group. Additionally, a total of 45 volatile components were detected, namely, 14 aldehydes, 14 alcohols, 9 ketones, 3 acids, 3 esters, 1 ether, and 1 amine. Alcohols (29.96% to 34.85%) and aldehydes (21.07% to 22.75%) were the predominant volatiles. Multivariate statistical analysis revealed 22 key differential fats and 26 differential odor substances as distinguishing labels between sexes. Correlation analysis revealed that the concentrations of triethylamine, dimethyl sulfide, ethanol-D, and 3-methyl butanal-D were significantly positively correlated with the concentrations of diglyceride (DG) (26:6e), cardiolipin (CL) (59:4), acylcarnitine (AcCa) (22:4), and triglyceride (TG) (52:10) (p < 0.01). Threefold cross-validation revealed that the prediction accuracies of these differential lipids and volatile compounds for sex recognition via the random forest model were 100%. These findings might not only provide insight into the effects of sexes on the lipid and volatile profiles of giant salamander tails but also provide clues for their gender recognition.

This study investigated the quality changes of dry salted mackerel during curing and drying process and the relationship between flavor substances and microorganisms. The results showed that the thiobarbituric acid reactive substances (TBARS) values increased gradually with the increase of salt concentration and treatment time. The total volatile base nitrogen (TVB-N) values and total viable counts (TVC) values showed the same trend. Under 3% condition, the TVB-N values exceeded the standard and was not suitable for consumption. A total of 61 volatile flavor substances were identified by Gas chromatography-ion mobility spectrometry (GC-IMS), among which aldehydes contributed the most. Staphylococcus and Cobetia were the most abundant by High-throughput sequencing (HTS). There was significant correlation between TOP15 microorganisms and TOP20 flavor substances. Staphylococcus and Cobetia were positively correlated with 13 volatile flavor substances, which contributed to the formation of flavor in naturally fermented Spanish mackerel.

Chilled and cut chicken is preferred by consumers for its safeness and readiness to cook. To evaluate the quality characteristics of various chilled chicken products, differences in volatile organic components (VOCs) of six different cut parts (breast, back, leg, heart, liver, and gizzard) of Lueyang black chicken were characterized through gas chromatography–ion mobility spectroscopy (GC-IMS) combined with stoichiometry. A total of 54 peaks in the signal of VOCs were detected by GC-IMS, and 43 VOCs were identified by qualitative analysis. There were 22 aldehydes (20.66–54.07%), 8 ketones (25.74–62.87%), 9 alcohols (4.17–14.69%), 1 ether (0.18–2.22%), 2 esters (0.43–1.54%), and 1 furan (0.13–0.52%), in which aldehydes, ketones, and alcohols were the main categories. Among the six cut parts, the relative content of aldehydes (54.07%) was the highest in the gizzard, and the relative content of ketones (62.87%) was the highest in the heart. Meanwhile, the relative content of alcohols (14.69%) was the highest in the liver. Based on a stable and reliable predictive model established by orthogonal partial least squares–discriminant analysis (OPLS-DA), 3-hydroxy-2-butanone (monomer and dimer), acetone, 2-butanone monomer, hexanal (monomer and dimer), isopentyl alcohol monomer, and n-hexanol monomer were picked out as characteristic VOCs based on variable importance in projection (VIP value > 1.0, p < 0.05). Principal component analysis (PCA) and the clustering heatmap indicated that the characteristic VOCs could effectively distinguish the six cut parts of Lueyang black chicken. The specific VOCs responsible for flavor differences among six different cut parts of Lueyang black chicken were hexanal (monomer and dimer) for the gizzard, 2-butanone monomer and hexanal dimer for the breast, hexanal monomer for the back, 3-hydroxy-2-butanone monomer for the leg, 3-hydroxy-2-butanone (monomer and dimer) for the heart, and acetone and isopentyl alcohol monomer for the liver. These findings could reveal references for quality assessment and development of chilled products related to different cut parts of Lueyang black chicken in the future.

Variations in volatile flavor components in pigmented onion bulbs (purple, white, and yellow) before and after cooking were characterized by headspace gas chromatography-ion migration spectrometry (HS-GC-IMS) to investigate their odor traits. Results showed that 39 and 45 volatile flavor compounds were identified from pigmented onion bulbs before and after cooking via the HS-GC-IMS fingerprinting, respectively. Sulfurs (accounting for 50.65%–63.42%), aldehydes (13.36%–22.11%), and alcohols (11.32%–17.94%) ranked the top three prevailing compound categories in all pigmented onions (both raw and cooked). Compared to the raw colored onion bulbs, the relative proportion of sulfurs in cooked onions decreased, whereas the relative proportion of alcohols, esters, pyrazines, and furans increased. Two reliable prediction models were established through orthogonal partial least squares-discriminant analysis (OPLS-DA), and 8 and 22 distinctive odor compounds were sieved out by variable importance in projection (VIP>1.0) as volatile labels, respectively. Both principal component analysis (PCA) and clustering heatmap exhibited favorable distinguishing effects for various pigmented onion bulbs before and after cooking. These results might offer insights into understanding the odor characteristics of different pigmented onions.

Steamed chicken breast meat attracts people for its unique flavor and nutritional benefits. In this study, the sensory evaluation of Lueyang black chicken breast meat during steaming was first performed, and their volatile organic compounds (VOCs) were further analyzed by gas chromatography-ion mobility spectroscopy (GC-IMS) combined with stoichiometry. The sensory results demonstrated that the Lueyang black chicken breast meat steamed for 15–30 min was more acceptable in taste, flavor, and chewiness. A total of 60 volatile flavor signal peaks were obtained, and 46 VOCs were recognized from qualitative analysis, containing 24 aldehydes (51.19–72.57%), 8 ketones (10.15–16.97%), 9 alcohols (7.98-13.16%), 2 furans (2.24–10.85%), 2 esters (0.54–1.56%), and 1 ether (0.05–2.47%). A stable and reliable prediction model was set up by orthogonal partial least squares-discriminant analysis (OPLS-DA), and 18 characteristic VOCs (including 10 aldehydes, 3 alcohols, 3 ketones, 1 furan, and 1 ether) were picked out through variable importance in the projection (VIP>1.0 and p

Jiuqu is one of the important raw materials for brewing Chinese rice wine (Huangjiu), often known as the “bone of wine”. In this study, the microbial community and flavor substances of Jiuqu made with different amounts of shiitake mushroom (Lentinula edodes) were investigated through high-throughput sequencing technology and headspace gas chromatography–ion migration spectroscopy (HS-GC-IMS), using traditional wheat yeast as a control. The results showed that 1593 genera and 5507 species were identified among the four types of yeast, with Aspergillus and Paecilomyces being the most dominant microorganisms at the genus level. Carbohydrate, coenzyme, and amino acid metabolism may be the main metabolic processes of the dominant microorganisms in Jiuqu. In terms of flavor, a total of 79 volatile substance monomers and some dimers were detected from four types of Jiuqu raw materials, with the main substances being 12 aldehydes, 19 ketones, 13 alcohols, 19 esters, 4 olefins, 1 acid, 3 ethers, 4 furans, 1 pyrazine, 1 pyridine, 1 triethylamine, and 1 thiazole. The correlation results indicate that Aspergillus, Lactobacillus, and Vibrio correlate significantly with the volatile flavor compounds unique to shiitake mushrooms and also have a positive effect on alcohol, esters, and furans. These results could shed light on the selection of Lentinula edodes as a fermentation starter for Huangjiu in the Qinba Mountain area.

In order to investigate the effects of different yeasts on the quality and flavor of sweet potato bread, the rheological properties, color, texture and flavor of sweet potato bread were compared and analyzed. The results showed that different yeasts had significant effects on the color, texture and flavor of sweet potato bread. The results of dynamic rheology showed that the G' and G" of yeast No.4 fermented dough were significantly higher than other groups(P

This study investigated the effects of different cooking methods on non-volatile flavor (free amino acids, 5′-nucleotides, and organic acids, etc.) of Coregonus peled meat. The volatile flavor characteristics were also analyzed by electric nose and gas chromatography-ion migration spectrometry (GC-IMS). The results indicated that the content of flavor substances in C. peled meat varied significantly. The electronic tongue results indicated that the richness and umami aftertaste of roasting were significantly greater. The content of sweet free amino acids, 5′-nucleotides, and organic acids was also higher in roasting group. Electronic nose principal component analysis can distinguish C. peled meat cooked (the first two components accounted for 98.50% and 0.97%, respectively). A total of 36 volatile flavor compounds were identified among different groups, including 16 aldehydes, 7 olefine aldehydes, 6 alcohols, 4 ketones, and 3 furans. In general, roasting was recommended and gave more flavor substances in C. peled meat.

In order to explore the changes of physicochemical indexes and volatile components of giant salamander meat during cold storage (4 ℃, 0~8 d), the sensory evaluation, total volatile basic nitrogen (TVB-N) value and total bacterial count of giant salamander meat during cold storage were regularly determined, and headspace solid phase microextraction combined with gas chromatography-mass spectrometry (HS-SPME-GC-MS) was used to analyze the changes of volatile components in giant salamander meat. The results showed that the sensory quality of giant salamander meat decreased gradually with the extension of refrigeration time, while TVB-N and total bacterial count increased. Among them, the sensory quality of giant salamander meat was not acceptable on the 5th day, the TVB-N value exceeded the upper acceptable limit (30 mg/100 g) on the 7th day, and the total bacterial count exceeded the upper acceptable limit (6 lg CFU/g) on the 6th day. A total of 58 volatile substances in 7 categories were detected in giant salamander meat at different refrigerating times. Among them, the contents of 14 alcohols and 12 esters were relatively higher. With the extension of refrigeration time, the alcohol content decreased, while the ester content increased, and other compounds fluctuated slightly during refrigeration storage. Cluster analysis showed that the giant salamander meat with different refrigeration time could be clustered into four categories, namely, 0~4 d, 5 d, 6~7 d, and 8 d. Correlation analysis showed that hexyl caproate, ethyl 2-methylbutyrate, 2-heptanone, 2, 3-butanedione and linalool could be used as potential markers of corruption and deterioration of giant salamander meat during cold storage. This study provides a reference for the freshness evaluation and quality control of giant salamander meat during cold storage.

Plasma is a new technology used to modify myofibrillar proteins (MPs) structure and promote protein aggregation. In order to study the mechanism of plasma modifying MPs thus the effects on qualities of MP gels, MPs were extracted by 0.6 M NaCl solution prepared with plasma-activated water (PAW) at different treatment time (0 s, 30 s, 60 s, 120 s, 240 s). With the prolonged PAW treatment time from 0 to 240 s, the pH values of natural MP solutions decreased significantly from 5.91 to 2.61 (P

In this study, blueberry anthocyanins, gelatin and Fe2+ were incorporated into zein matrix via electrospinning method to prepare colorimetric indicator films for monitoring milk freshness. Gelatin and Fe2+ were incorporated into the film to improve visual discrimination of indicator films’ color changes in milk with different freshness degrees and in solution with pH 3–7. Results of SEM, FT-IR and XRD showed that there were intermolecular hydrogen bonds among components, which associated with the larger color difference of indicator films. UV–vis spectral analysis showed that blueberry anthocyanin solutions containing both gelatin and Fe2+ displayed the highest intensity absorption peaks. The optimal ability to distinguish the pH (3–7) of solutions was presented by the indicator film incorporating gelatin (1% (w/v)) and Fe2+ (0.07 mg/mL). Gelatin and Fe2+ increased the color-responsive sensitivity of the indicator film to pH. The film could be successfully used to detect the freshness of milk, whose color changes were visually perceivable: from purple black (fresh milk) to royal purple (spoiling milk) and then to violet red (spoiled milk). The color parameters (L*, a*, R, G and B) of the film revealed a high correlation with the pH/acidity of the milk during storage. The successful application of the indicator film embedding gelatin and Fe2+ for monitoring milk quality changes indicated that the addition of special substances could provide great potential for monitoring freshness and preparing intelligent packaging of food.

To improve the antioxidant activity and flavor characteristics of giant salamander peptides, the changes in pH, browning extent, DPPH radical scavenging capacity, and reducing ability in Maillard reaction products (MRPs) between giant salamander peptides and glucose during the heating process (95°C and 0, 1, 2, 3, and 4 h) were investigated. The difference in volatile compounds of the MRPs was also analyzed by gas chromatography-ion mobility spectroscopy. The results indicated that the pH value of the MRPs shrank with the proceeding of heating time, while the browning extent and antioxidative capacity increased. 58 volatile compounds including 24 aldehydes, 12 alcohols, 8 esters, 5 ketones, 4 pyrazines, 2 furans, 1 pyridine, 1 ether, and 1 olefin were detected among the MRPs. At different stages of the reaction, the MRPs were dominated by aldehydes, and the relative amount of aldehydes first decreased and then increased with the intensification of the reaction time; the relative content of esters increased first and then decreased; the relative content of alcohols decreased gradually; and the relative amount of pyrazine and furan exhibited a significant increasing tendency. Principal component analysis (PCA) revealed that the cumulative contribution rate of the first two components reached 87.3%, indicating that the volatile compounds of MRPs at different reaction times were well differentiated. The correlation analysis demonstrated that the antioxidant activity was positively associated with the browning extent, ketones, furans, and pyrazines. These results might offer a certain reference for modifying the physicochemical traits of giant salamander peptides.

The differences of volatile organic compounds in commercially available foxtail millets with different colors (black, green, white and yellow) were assayed through gas chromatography-ion migration spectrometry (GC-IMS) to explore their volatile flavor characteristics. Fifty-five volatile components were found in various colored foxtail millets, including 25 kinds of aldehydes (accounting for 39.19–48.69%), 10 ketones (25.36–32.37%), 15 alcohols (20.19–24.11%), 2 ethers (2.29–2.45%), 2 furans (1.49–2.95%) and 1 ester (0.27–0.39%). Aldehydes, alcohols and ketones were the chief volatiles in different colored foxtail millet, followed by furans, esters and ethers. These identified volatile flavor components in various colored foxtail millets obtained by GC-IMS could be well distinguished by principal components and cluster analysis. Meanwhile, a stable prediction model was fitted viapartial least squares-discriminant analysis (PLS-DA), in which 17 kinds of differentially volatile components were screened out based on variable importance in projection (VIP>1). These findings might provide certain information for understanding the flavor traits of colored foxtail millets in future.

Changes in flavor volatiles of three colored wheat grains (black, green, and yellow) after cooking were detected via gas chromatography-ion migration spectrometry (GC-IMS) to explore corresponding volatile flavor traits. A total of 52 volatile chemicals were spotted among these cooked wheat grains, including 30 aldehydes (accounting for 73.86–83.78%), 11 ketones (9.53–16.98%), 3 alcohols (0.88–1.21%), 4 furans (4.82–7.44%), 2 esters (0.28–0.42%), and 2 pyrazines (0.18–0.32%). Aldehydes, ketones, and furans were the main volatile compounds in three different cooked wheat. For black-colored wheat, the relative contents of benzene acetaldehyde, benzaldehyde, 2-methyl butanal, and 3-methyl butanal were much higher (p

Sturgeons are a type of subcold water fish distributed in eastern Europe, on both sides of the North Pacific, in eastern Asia, in western North America, and on the east coast of North America. Its production capacity is strong, and it is easy to breed. However, the sturgeon industry has the problems of a single product structure, a short industrial chain and poor market sales. In this context, developing the sturgeon industry is crucial to research the nutritional value of sturgeon processing byproducts and developing diversified products. Therefore, this paper summarizes the research on the nutritional value of sturgeon processing byproducts and the current situation of processing and utilization over the past 10 years. First, CiteSpace visual analysis software and the bibliometric analysis platform were used to analyze the status of sturgeon research. The Web of Science (WOS) database was used as the literature source to fit the keywords of sturgeon literature in the past ten years. After excluding the two keywords sturgeon and sturgeon meat, the relevant literature is analyzed and sorted, focusing on the literature in the last five years. Second, a comprehensive and in-depth review (sturgeon, processing, byproducts as the keywords to search Google Scholar and Web of Science) was conducted on the research of the nutritional components contained in sturgeon and the processing of nutritional components in byproducts to provide a reliable reference for the research and processing of the sturgeon industry.

Graphene and its derivatives have been a burning issue in the last 10 years. Although many reviews described its application in electrochemical detection, few were focused on food detection. Herein, we reviewed the recent progress in applying graphene and composite materials in food detection during the past 10 years. We pay attention to food coloring materials, pesticides, antibiotics, heavy metal ion residues, and other common hazards. The advantages of graphene composites in electrochemical detection are described in detail. The differences between electrochemical detection involving graphene and traditional inherent food detection are analyzed and compared in depth. The results proved that electrochemical food detection based on graphene composites is more beneficial. The current defects and deficiencies in graphene composite modified electrode development are discussed, and the application prospects and direction of graphene in future food detection are forecasted.

Previous studies have suggested that polypeptides extracted from milk, soybean, fish, eggs, and meat possess potential anti-inflammatory effects. To date, few studies have reported the anti-inflammatory function of sturgeon peptides and their underlying mechanisms are unknown. The current study was therefore to determine the anti-inflammatory potential of sturgeon peptides with lipopolysaccharide (LPS)-induced RAW264.7 inflammatory model. Pepsin hydrolysate (PeH) was purified by ultrafiltration and Sephadex G-15 gel filtration chromatography. PeH significantly reduced the inflammatory mediator (NO) and inflammatory cytokines (IL-6, TNF-α and IL-1β) expression in a dose-dependent manner. Moreover, the purified sturgeon peptide (F2) possessed strong antioxidant potential and effectively inhibited DPPH and ABTS free radicals. F2 significantly suppressed the expression of MAPK, IκBα, and NF-κB p65, indicating that F2 exerted anti-inflammatory influence by the inhibition of MAPK and NF-κB pathways.

Drying is one of the most common methods for processing and preserving sea cucumber. Based on the research of pretreatment and drying process, this paper develops a dried sea cucumber product that can be quickly rehydrated in only 8 hours. By setting the pretreatment at heated water temperature of 80°C and the drying temperature from 30°C to 60°C, the fitting model is found by comparing empirical formulas and artificial neural networks. The ANN-based model was demonstrated to fit the experimental data for the adequate drying of sea cucumber. Following the increased drying temperature, the drying time was decreased and the rehydration ratio was increased. The sensory evaluation and texture properties dried at 40°C and 50°C were much better than those dried at 30°C and 60°C. Microstructure of rehydrated dried sample showed that increasing the temperature leads to the increase of fiber pore space, and the rehydration rate increases. The results of drying time and the rehydration properties of sea cucumber showed that 50°C is the best drying condition for hot-air drying of sea cucumber. The developed rapid rehydration dried sea cucumber can effectively simplify the rehydration time and steps of the dried sea cucumber and improve the quality of the sea cucumber, and it is considered to be a good technology for drying the sea cucumber and making a fast rehydration dried sea cucumber that can be further used for value-added product.

The global production of farmed Atlantic salmon amounts to over 2 million tons per year. Consumed all over the world, salmon is not only delicious but also nutritious. This paper deals with the relationship between moisture content, low-field nuclear magnetic resonance (LF-NMR), scanning electron microscope (SEM), and sensory evaluation in the baking process of salmon. An artificial neural network (ANN) model has been established to simulate the change of moisture content and energy consumed in the baking process. Through the study of LF-NMR, SEM, and sensory evaluation, it was found that the change of sensory indexes was consistent with the results observed by LF-NMR and SEM. With the increase of temperature, muscle fibers contracted, the interstices increased, the rate of water loss increased, and the sensory score decreased. Initial moisture content, baking time, baking temperature, baking humidity, and baking air velocity were employed as the baking control parameters for the ANN. ANN can be used to determine the moisture content and energy consumed of baking salmon. The best network topology occurred with 5 input layer neurons, 17 hidden layer neurons, and 2 output layer neurons, and the MSE was 0.00153, and Rall was 0.99661. According to the experiment, it was demonstrated that the ANN is a reliable software-based method.

Consumers prefer natural over synthetic chemical preservatives on a food label. Therefore, it is crucial to ensure the safety and efficacy of such natural preservatives. The emergence of heat-resistant spore-forming Alicyclobacillus spp. has been associated with spoilage problems in the fruit juice industry. Herein, a bacteriocin-producing stain YKX was isolated from the traditional pickles in Hanzhong City, China, and it was identified as Lactobacillus plantarum by morphological, biochemical, physiological, and genotypic features. A stable bacteriocin, plantaricin YKX, was isolated, purified, and tested for its efficacy against Alicyclobacillus acidoterrestris. Plantaricin YKX is a 14-amino acid peptide (Lys-Tyr-Gly-Asn-Gly-Leu-Ser-Arg-Ile-Phe-Ser-Ala-Leu-Lys). Its minimal inhibitory concentrations (MICs) against the tested bacterial and fungal strains were ranged from 16 to 64 μg/mL. It is thermostable and active at pH 3–8. The flow cytometry data and microscopic observations suggested that plantaricin YKX can augment cell membrane permeability, induce potassium ion leakage and pore formation, and disrupt cell membranes. It also affects spore germination and guaiacol production of A. acidoterrestris, probably due to upregulation of the luxS gene linked to quorum sensing.

Research has shown that cartilage containing chondroitin sulfate and protein presents versatile bioactivities. Chondroitin sulfate in cartilage is beneficial to activate the immune system while the protein/peptide has not been fully understood. The current study investigated the antioxidant and anti-inflammatory properties of ethanol-soluble hydrolysates of sturgeon cartilage (ESCH) prepared through hot-pressure, enzymatic hydrolysis and ethanol extraction. UV spectrum, IR and agarose gel electrophoresis results suggested the successful exclusion of chondroitin sulfate from peptides. Nitric oxide (NO) floods in cells activated by inflammation. It was inhibited when administrated with ESCH. To further explain the observed anti-inflammatory activity, ESCH was separated with Sephadex G-15 into 3 components, among which F3 showed a higher NO inhibition rate and significantly reduced the production of the proinflammatory cytokine IL-6. In addition, the yield of IL-10 increased. Western blotting suggested that F3 downregulated the NO content and IL-6 level by suppressing Mitogen-activated protein kinases (MAPK) channels. Moreover, both ESCH and F3 showed DPPH and ABTS free radical scavenging abilities which was possibly related to the anti-inflammatory property. These results indicated that ESCH behaved anti-inflammatory and antioxidant activities. Cartilage may be a good source to produce anti-inflammatory peptides.

Quality attributes and water mobility of giant salamander jerkies (GSJs) during roasting process (160°C, for 0, 20, 40, 60, and 80 min) were investigated. The results showed that a∗,b∗ values and shear force increased of GSJs roasting from 20 to 80 min, while L∗, yield, and moisture content decreased significantly (p

Effects of deep fat frying and hot air frying on texture, color difference, sensory score, yield, fat content, and volatile flavor compounds of giant salamander meatballs before and after frying were investigated. The results showed that, compared with the deep fat frying group, hot air-fried giant salamander meatballs had higher hardness, elasticity, and L∗ (p0.05). Gas chromatography ion migration chromatography (GC-IMS) was used for flavor compound analysis, and 50 flavor compounds were analyzed, containing 22 aldehydes, 11 ketones, 6 olefins, 4 acids, 3 esters, 3 alcohols, and 1 phenol. Compared with the samples before frying, the relative contents of aldehydes and ketones of fried giant salamander meatballs increased significantly, while the relative contents of esters and alkenes decreased significantly. Principal component analysis showed that the GC-IMS spectra of volatile flavor compounds before and after deep fat frying and hot air frying varied greatly, and the cumulative contribution rate of the two principal components reached 86.1%, indicating that the GC-IMS technology might be used to distinguish giant salamander meatballs before and after frying, or with different frying methods. These results may offer a note for development and quality control of the precooked giant salamander meatballs in the future.

Previous studies have demonstrated that polypeptides extracted from fish protein possess potential anti-inflammatory effects, but few studies have reported the underlying anti-inflammatory mechanism of sturgeon peptides. Hence, the goal of this study was to explore the peptide sequences with potential anti-inflammatory activity derived from sturgeon muscle protein in the lipopolysaccharide (LPS)-induced RAW264.7 inflammatory model. Fourteen novel peptides were identified in major muscle proteins by mass spectrometry, and three synthetic peptides – KIWHHTF, VHYAGTVDY, and HLDDALRGQE - decreased the release of inflammatory mediators and inflammatory cytokines (NO, IL-6, and IL-1β), while increasing SOD activity significantly in the LPS-induced RAW264.7 inflammatory model. Western blotting analysis revealed that these peptides suppressed the phosphorylation levels of MAPKs, indicating that these peptides exerted anti-inflammatory effects by inhibiting the MAPK pathway. The novel peptides potentially have application prospects as functional food ingredients.

The objective of this study was to investigate the effects of different enzymolysis conditions on the NO inhibition rate and DH (degree of hydrolysis) of sturgeon hydrolysates (SH) prepared by Alcalase. The NO inhibition rate of 60.23% was attained under the optimum enzymolysis conditions as follows: pH 9.0, enzymolysis time of 4.92 h, enzymolysis temperature of 55°C, solid/liquid ratio of 1 : 20, and enzyme additive amount of 7674.22 U/g protein, which was well matched with the predicted value 61.44% of the Box–Behnken design model. After the ultrafiltration of SH, SH-3 (SH

Microbial contamination is one of the most common food safety issues that lead to food spoilage and foodborne illness, which readily affects the health of the masses as well as gives rise to huge economic losses. In this study, Channa argus was used as a source of antimicrobial agent that was then analyzed by untargeted metabolomics for its antibacterial mechanism against Staphylococcus aureus. The results indicated that the skin mucus extract of C. argus had great inhibitory action on the growth of S. aureus, and the morphology of S. aureus cells treated with the skin mucus extract exhibited severe morphological damage under scanning electron microscopy. In addition, metabolomics analysis revealed that skin mucus extract stress inhibited the primary metabolic pathways of S. aureus by inducing the tricarboxylic acid cycle and amino acid biosynthesis, which further affected the normal physiological functions of biofilms. In conclusion, the antimicrobial effect of the skin mucus extract is achieved by disrupting cell membrane functions to induce an intracellular metabolic imbalance. Hence, these results conduce to amass novel insights into the antimicrobial mechanism of the skin mucus extract of C. argus against S. aureus.

Abstract Yak butter is one of the most important foods for the Tibetan people. Of note, its production yields waste yak milk as a by-product. In this work, waste yak milk protein hydrolysates made via Pepsin hydrolysis were shown to have antimicrobial activity. Furthermore, an innovative method of magnetic liposome adsorption combined with reversed-phase high performance liquid chromatography (RP-HPLC) was developed to screen for and purify the antimicrobial peptides. Two antimicrobial peptides were obtained and their amino acid sequences were determined by N-sequencing, namely Arg-Val-Met-Phe-Lys-Trp-Ala and Lys-Val-Ile-Ser-Met-Ile. The antimicrobial activity spectra of Arg-Val-Met-Phe-Lys-Trp-Ala included Bacillus subtilis, Staphylcoccus aureus, Listeria innocua, Escherichia coli, Enterobacter cloacae and Salmonella paratyphi, while the Lys-Val-Ile-Ser-Met-Ile peptide shows not only bacterial growth inhibition but also of fungi. Haemolytic testing suggested that these two antimicrobial peptides could be considered to have no haemolytic effect at their minimum inhibitory concentrations (MICs).

The gonad of jellyfish (Rhopilema esculentum Kishinouye), containing high protein content with a rich amino acid composition, is suitable for the preparation of bioactive peptides. Jellyfish gonad was hydrolysed with neutral protease to obtain jellyfish gonad protein hydrolysate (JGPH), which was then purified sequentially by ultrafiltration, gel filtration chromatography, and RP-HPLC. The peptides were characterized with HPLC-MS/MS. One peptide with amino acid sequence Ser-Tyr (SY) was identified and synthesized, which showed good ACE inhibitory and antioxidant activity. The IC50 of this peptide on DPPH, ·OH, super oxygen anion scavenging activities, and ACE inhibitory activity are 84.623 μM, 1177.632 μM, 456.663 μM, and 1164.179 μM, respectively. The anchor in the binding site of SY and ACE C-domain (ACE-C) was obtained by molecular simulations. The results showed that the dipeptide purified from jellyfish gonad protein hydrolysates can be used as functional food material and is helpful in the study of antioxidant and inhibition of ACE.