Objective To optimize the fermentation condition of Enterococcus faecium with the capability of high-yield biogenic amine production by response surface design. Methods Based on the previous single factor experiment results, response surface methodology was used to investigate the interaction among 3 factors with different levels, namely culture temperature (10, 15, 20 ℃), initial pH (5.0, 5.5, 6.0), and sodium chloride addition (4.5%, 5.5%, 6.5%), on the production of biogenic amines by Enterococcus faecium. The fermentation condition for controlling the production of tyramine and phenethylamine by Enterococcus faecium were optimized. Results The results showed that the regression equations for the production of tyramine and phenethylamine at 48 h were obtained with R²=0.9866, adjusted R²=0.9693 for tyramine and R²=0.9875, adjusted R²=0.9714 for phenethylamine, the order of affecting the production of casein and phenethylamine was culture temperature>NaCl addition>initial pH.. The optimal fermentation condition to control the tyramine production of Enterococcus faecium was initial pH of 6.0, incubation temperature of 10.9 ℃, and NaCl addition level of 4.5%. The optimal fermentation condition to control the phenylethylamine production was initial pH of 5.34, incubation temperature of 13.8 ℃, NaCl addition level of 5.8%. Conclusion The results provide references for the effective control of the biogenic amine production of Enterococcus faecium growing in fermented food such as fermented meat products.

Objective To process, annotate and analyze the genomic data of the high temperature resistant Bacillus amyloliticus BA-DES4 by biological software and databases, and to functionally annotate the strain characteristics at the gene level. Methods Metabolic signaling pathways were analyzed by metabolic signaling pathways kyoto encyclopedia of genes and genomes (KEGG) and gene ontology (GO), clusters of orthologous groups of proteins (COG), non-redundant protein (NR) database, etc., which were compared with the predicted gene sequences to obtain the gene function annotation table. The protein sequences of the predicted genes were compared with COG, KEGG and GO databases for BLASTP analysis, to realize the prediction of gene annotation information and function prediction. Results The database analysis showed that the number of bases was 4188731, and the GC content accounted for 46.18%. There were 4445 protein genes, with a total length of 3696380 bp. Functional annotation of genomic protein coding genes showed that the highest proportion of COG-annotated genes was for G (carbohydrate transport and metabolism), followed by K (transcription), which indicated that protein genes encoded in the COG database were mainly involved in the basic cellular function. The GO annotation revealed that the predominant gene types and genes were classified under biological processes. The carbohydrate-active enzymes (CAZy) annotation identified hydrolytic enzymes as the most prevalent category. The KEGG annotation showed that carbohydrate metabolism accounted for the highest number of genes. In the environmental information category, information transduction emerged as the most significant percentage. In the high-temperature resistant Bacillus amyloliticus BA-DES4, 11 genes were found to encode cellulases, with β-glucosidase and endoglucanase being the genes encoding enzymes. Conclusion In this study, the genomic data of Bacillus amyloliticus BA-DES4 is processed, annotated and analysed in order to further explore the research potential of the strain, to better investigate the regulatory mechanism of cellulose production in Bacillus amyloliticus BA-DES4 and to provide a theoretical basis for subsequent experiments.

Objective To optimize the fermentation process with fresh Capsicum annuum L. as raw materials using Lactiplantibacillus plantarum L. and analyze the quality of fermented Capsicum annuum L. under the optimized conditions. Methods Using single factor and orthogonal experiments, the fermentation parameter of fermented Capsicum annuum L. inoculated with lactic acid bacteria were optimized and verified for the optimized fermentation condition. The changes of total acid, reducing sugar, nitrite content, and volatile substances were studied during the fermentation process of Capsicum annuum L. under the condition of the optimal parameters. By comparative analysis, the quality characteristics of strongly fermented Capsicum annuum L. were obtained. Results Under the condition of optimized fermentation parameters (fermentation temperature 35 ℃; fermentation time 10 d; lactic acid bacteria addition 4%; salt addition 4%), fermented Capsicum annuum L. showed sensory scores of 83.00±0.16, pH 3.38±0.02, total acid content of (15.55±0.24) g/kg, L^* of 36.76±0.82, a^* of 22.45±0.65, b^* of 4.04±0.43, and soluble solid substance of (13.07±0.03)%. Lactic acid and malic acid were the main organic acids of fermented Capsicum annuum L., and their contents were (1.9611±0.0800) mg/mL and (1.8600±0.1000) mg/mL, respectively. The flavor substances mainly included acids, esters, ketones, alcohols, and hydrocarbons. Among them, acids accounted for 65.45% of the relative content of total flavor substances. Conclusion Fermentation with lactic acid bacterium strain can enhance brightly fresh redness, crisp, rich aroma, suitable acidity, uniform texture and excellent taste, which are widely accepted by consumers.

Objective To investigate the uric acid-lowering effects of compound postbiotic powder in hyperuricemia. Methods In vitro experiments verified that the metabiotic powder had 2 kinds of effects: Inhibiting xanthine oxidase (XOD) activity and degrading uric acid, and then establishing a rat hyperuricemia model, and giving postbiotic powder treatment, respectively, the changes in body weight, joint growth, serum uric acid (UA) content, serum XOD activity, liver and kidney function, and total cholesterol (TC) in blood lipids, triglyceride (TG) level were compared. Results The sample significantly reduced the serum UA content, serum urea nitrogen (BUN), creatinine (Cr) and TC levels in rats with hyperuricemia. It could effectively reduce the activities of serum XOD, aspartate aminotransferase (AST) and alanine aminotransferase (ALT). Conclusion Postbiotic powder has the effect of lowering uric acid, and also has a certain therapeutic effect on liver and kidney injury and dyslipidemia caused by hyperuricemia, and the therapeutic effect is positively correlated with the intake of postbiotic powder.

Objective To investigate the pollution of organophosphorus flame retardants (OPFRs) in soil and nuts in the primary Carya illinoensis production areas of Anhui Province, and evaluate the ecological risk and human health risk. Methods A total of 15 soil and nut samples were collected from the main production areas of Carya illinoensis in Anhui Province, and the pollution characteristics of 14 kinds of OPFRs were analyzed. The ecological risk of soil was evaluated using the risk quotient (RQ) method, and the human health risk of consuming nuts was assessed using a health risk assessment model. Results The concentration range of OPFRs in soil samples from Carya illinoensis production areas in Anhui Province was 162.33-394.48 μg/kg, with an average of 305.83 μg/kg. Tris(2-ethylhexyl)phosphate (TEHP) had the highest detection concentration, at 52.62 μg/kg. The concentration range of OPFRs in nut samples was 127.57-310.81 μg/kg, with an average of 223.93 μg/kg. Tris(2-ethylhexyl) phosphate (TEHP) had the highest detection concentration, averaging 46.82 μg/kg. The RQ values of 11 kinds of OPFRs ranged from 3.50×10^-5 to 0.47, with tris(1,3-dichloro-2-propyl) phosphate (TDCIPP), triphenyl phosphate (TPhP), and 2-ethylhexyl diphenyl phosphate (EHDPP) having RQ values between 0.1 and 1.0. The remaining RQ values were all less than 0.1. The health risk assessment of human intake of pecan showed that the hazard quotient (HQ) values of children and adults were both less than 0.1, and the risk of intake of TBEP was higher in children and adults, with the HQ value of adults slightly higher than that of children. Conclusion There is a particular ecological risk of OPFRs in the soil of some production areas of Carya illinoensis in Anhui Province, and the residues of OPFRs in nuts can be ignored in terms of human health risk. This study provides a basis for the safety assessment of novel pollutants in the soil and nuts of Carya illinoensis production areas.

Objective To understand the residual levels of chlorpyrifos in vegetables and fruits in Shanghai in 2014—2023, and evaluate the dietary exposure risk of chlorpyrifos in vegetables and fruits. Methods A number of different varieties of vegetables and fruits in Shanghai were inspected and monitored for the detection of chlorpyrifos from 2014 to 2023. Combined with the food consumption data of residents in Shanghai in 2013, dietary exposure risk assessment of chlorpyrifos were conducted by point assessment method. The assessment results were compared with the acute reference dose (ARfD) and acceptable daily intake (ADI) to assess the acute and chronic exposure risk of chlorpyrifos in vegetables and fruits in residents in Shanghai. Results The quantity of vegetables samples was 33796, the detection rate was 0.97%, the average value was 0.00131 mg/kg, and the exceedance rate was 0.46%. The quantity of fruits samples was 9228, the detection rate was 5.26%, the average value was 0.00320 mg/kg, and the exceedance rate was 0.00%. The acute exposure of chlorpyrifos residues ingested through vegetables and fruits were 0.0432 mg/kg bw and 0.0141 mg/kg bw, the ratio of acute exposure to ARfD respectively were 43.19% and 14.15% among the population aged 3 and above. The chronic exposure of chlorpyrifos residues ingested through vegetables and fruits were 5.34×10^-6 mg/kg bw and 8.43×10^-6 mg/kg bw, the ratio of chronic exposure to ADI respectively were 0.053% and 0.084%. Conclusion Both the acute and chronic exposure risks of chlorpyrifos ingested through vegetables and fruits in residents are low in Shanghai.

Objective To understand the contamination level of glycidyl esters (GE) in edible vegetable oils and to evaluate the dietary exposure risk of GE in Shanghai residents. Methods Based on the monitoring data of GE in edible vegetable oil sold in Shanghai in 2024, combined with the vegetable oil consumption data of Shanghai residents in 2024, the GE exposure of Shanghai residents via vegetable oil was calculated by simple distribution assessment method, and the margin of exposure (MOE) method was used to assess the health risk. Results The detection rate of GE in 178 edible vegetable oils was 94.4%, with an average content of 360.8 μg/kg and a maximum value of 5470.0 μg/kg. According to the EU regulations on the limit values of GE in vegetable oils, it was found that the exceeding standard rate of GE in vegetable oil was 5.6%. The mean content of GE in rice oil (1169.3 μg/kg) was the highest, followed by camellia seed oil (657.8 μg/kg) and corn oil (499.0 μg/kg). The mean daily exposure and 95th percentile exposure of GE from edible vegetable oils in Shanghai residents aged ≥3 years old were 0.208 and 0.497 μg/kg bw, the MOE values were 11538 and 4829, respectively, and P₉₅ MOE was less than 10000. The mean MOE value of GE exposure through vegetable oil in residents aged 3 to 17 years old was less than 10000. The P₉₅ MOE values of GE exposure through vegetable oil in 4 different age groups were all less than 10000. Conclusion The health risk of GE intake via edible vegetable oil in Shanghai residents is generally at an acceptable level. However, the health risks of GE exposure for individuals aged 3 to 17 year old and those with high consumption of vegetable oil still need to be focused.

Objective To compare the mold counting effects of potato dextrose agar and rose Bengal agar as 2 types of counting culture medium. Methods Growth rate, specificity, and selectivity were compared between potato dextrose agar and rose Bengal agar culture medium using 20 kinds of standard mold strains and 15 kinds of common foodborne pathogen strains. Additionally, the counting effects of both culture medium were assessed using 36 actual food samples and 174 swab samples from food contact environments in refrigerators. Results The growth rate (PR value) of the 20 kinds of mold strains on both potato dextrose agar and rose Bengal agar culture medium was greater than 0.7, and the selectivity (G value) was less than 1. However, molds on potato dextrose agar culture medium exhibited more typical colony morphology, indicating better specificity than rose Bengal agar culture medium. In the detection of actual samples, the detection rate of potato dextrose agar culture medium was relatively high, showing a significant difference compared to rose Bengal agar culture medium (χ²=13.551, P=0.001). It exhibited a particularly higher detection rate in samples with low contamination (χ²=9.929, P=0.001). However, for highly contaminated samples, rose Bengal agar culture medium was more convenient for counting. Conclusion Using a single culture medium can affect counting results. It is recommended to apply 2 types of culture medium or select an appropriate counting medium based on the contamination level when conducting mold counting tests on food samples.

Objective To explore the contents of 7 kinds of elements in agricultural products in a certain area in North China plain, including lead (Pb), cadmium (Cd), mercury (Hg), arsenic (As), tin (Sn), nickel (Ni) and chromium (Cr), and evaluate the safety risks of dietary ingestion. Methods The samples were pretreated by microwave digestion, and the contents of 7 kinds of heavy metals in 611 agricultural products collected in the certain area from 2022 to 2024 were determined by inductively coupled plasma mass spectrometry (ICP-MS). Index (P_i), Nemero comprehensive pollutant index (P_N) and target hazard quotient/total target hazard quota (THQ/TTHQ) were used to evaluate the pollution levels of heavy metals in agricultural products. Results All elements except Hg were detected in the agricultural products. Among them, the content of Pb and Cr in individual samples exceeded the limit values specified in GB 2762—2022 National food safety standard-Limits of contaminants in foods (Pb≤0.2 mg/kg, Cr≤0.5 mg/kg). The overall content levels of the 7 kinds of elements were relatively low, and their order in the agricultural products was Ni (0.192 mg/kg)>Cr (0.040 mg/kg)>Pb (0.017 mg/kg)>Sn (0.011 mg/kg)>As (0.009 mg/kg)>Cd (0.005 mg/kg), the heavy metal content of agricultural products in different types and regions was quite different, and the THQ/TTHQ of all agricultural products was less than 1, and the P_i and P_N were less than 1. Conclusion The quality and safety of agricultural products in the study area are in good condition, and the level of heavy metal pollution is relatively low. However, there may be potential heavy metal exposure risks in some individual villages and towns in the southeastern part, and the dietary exposure risks for children are greater than those for adults.

Objective To investigate the extent of lead contamination in commercial foods and assess the health risk from dietary lead intake of the residents in Guangzhou in 2023. Methods In 2023, the 310 samples were collected from 3 food categories in 11 districts of Guangzhou, China. Lead was measured in the samples using inductively coupled plasma mass spectrometry. Dietary exposure to lead was calculated based on the food consumption survey of Guangzhou residents in 2011, and the health risk of the population was evaluated using the margin of exposure (MOE) method. Results Lead was detected in 83.23% of the overall samples, and the over-standard rate was 0%, with an average lead content of 0.040 mg/kg. The highest lead level was found in bivalves, 0.205 mg/kg. The average daily dietary lead exposure of the whole population and all age groups (3-6 years old, 7-17 years old, 18-59 years old, and 60 years old and above) in Guangzhou and the consumers with high dietary exposure of all age groups (95th percentile P₉₅) were: 0.082, 0.120, 0.097, 0.078, 0.081 μg/(kg·d) and 0.225, 0.330, 0.268, 0.206, 0.226 μg/(kg·d). The contribution of rice and rice products, brassica vegetables, and leafy vegetables to dietary lead exposure was relatively significant. The MOE values for lead in residents of all age groups were greater than 1, with the MOE values for minors being lower than those for adults, particularly among high dietary exposure populations. Conclusion In 2023, there is a certain degree of lead contamination in the food items under close watch in the Guangzhou market. The average dietary lead exposure of residents of all age groups is within the acceptable range. However, it is still necessary to pay attention to key food items and take measures to reduce the dietary lead exposure risk for residents in Guangzhou.

Objective To evaluate the dietary exposure levels of lead, cadmium, arsenic and chromium in Triticum aestivum L. in Anhui Province in 2023 and to evaluate dietary health risks combined with population consumption. Methods A total of 212 Triticum aestivum L. samples collected from Anhui Province in 2023 were analyzed for plumbum, cadmium, arsenic, and chromium content using inductively coupled plasma mass spectrometry (ICP-MS). The contamination status of the 4 kinds of elements was evaluated using the contamination index method. The margin of exposure (MOE) was used for plumbum exposure assessment, while the provisional tolerable monthly intake (PTMI) or benchmark dose level (BMDL) compared with dietary exposure, expressed as the margin of safety (MOS), was applied for cadmium and arsenic exposure assessment. For chromium, the dietary exposure (EXP) was calculated as a percentage of the tolerable daily intake (TDI). Results Among the 212 Triticum aestivum L. samples, As levels did not exceed the standard limits. The exceedance rates for cadmium, plumbum, and chromium were 1.89%, 1.42% and 7.55%, respectively. The single-factor contamination index for all elements was less than 1, indicating safety, while the comprehensive contamination index was 1.737, suggesting mild contamination. The average dietary exposure levels of plumbum, cadmium, and arsenic for residents of different age groups and cities in Anhui Province showed MOE and MOS values greater than 1, and the EXP/TDI percentage for chromium was less than 1. However, for high-exposure P_97.5 populations, including children aged 13-36 months and 7-12 years, the EXP/TDI percentage for chromium exceeded 1. Similarly, in northern Anhui cities such as Fuyang, Huaibei, and Suzhou, the EXP/TDI percentage for Cr in high-exposure P_97.5 populations also exceeded 1. Conclusion The exposure risk levels of plumbum, cadmium, arsenic, and chromium from Triticum aestivum L. consumption among Anhui residents are generally acceptable. However, special attention shall be given to children, adolescents, and high-exposure populations in Fuyang, Huaibei, and Suzhou.

Objective To investigate the contamination status and conduct a risk assessment of foodborne pathogens in food samples from Baotou City, Inner Mongolia, from 2016 to 2023. Methods According to the requirements of the Inner mongolia autonomous region food safety risk monitoring plan—Microbiological monitoring, food samples were collected from 10 counties and districts in Baotou City between 2016 and 2023. Detection of foodborne pathogens was performed following standard operating procedures. Results Over the 8-year period, a total of 1358 food samples from 17 major categories were collected, and 485 strains of pathogenic microorganisms belonging to 14 species were detected, with an overall detection rate of 26.58% (361/1358). Among the 11 categories of food samples with detected pathogens, meat and meat products, as well as aquatic products and their products, showed higher detection rates of 42.35% (227/536) and 47.78% (43/90), respectively. Food samples from sampling points such as farmers' markets and farming sites were heavily contaminated, with detection rates of 42.13% (75/178) and 61.22% (30/49), respectively. Among the pathogens, Vibrio alginolyticus and Campylobacter had higher detection rates of 40.00% (8/20) and 50.22% (113/225), respectively. The positive detection rate of monitored samples increased annually, rising from 1.05% (2/190) in 2016 to 50.00% (100/200) in 2023. Conclusion The contamination level of foodborne pathogens in meat and meat products, as well as aquatic products and their products, is relatively high in Baotou City. Sampling points such as farmers' markets pose a risk of causing foodborne diseases.

The popularization of the concept of health in the new era has made the public extremely concerned about food safety. As an important factor affecting food safety, multi-pesticide residues have become the focus of attention for dietary consumers. This paper focused on the cumulative dietary exposure risk of multi-pesticide residues and reviewed the research progress in this field at home and abroad, covering aspects such as assessment frameworks, assessment methods, assessment software and databases. Secondly, it discussed and analyzed the differences in the cumulative dietary risk assessment systems of different international organizations and countries as well as the latest research methods at home and abroad, such as the introduction of advanced data analysis technologies and the adoption of multidisciplinary research models, to comprehensively assess the cumulative dietary exposure risk of multi-pesticide residues. Thirdly, it clarified the importance of relevant databases and software in the assessment process and pointed out the difficulties in data grouping, acquisition and standardization in the current risk assessment research. Finally, it putted forward reasonable suggestions in view of the current situation and existing problems of the cumulative dietary risk assessment of multi-pesticide residues, aiming to provide theoretical support for food quality and safety and the green development of pesticides in the new era.

Objective To establish a method for the simultaneous determination of 24 kinds of β-blockers in eggs by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Methods The 80% acetonitrile aqueous solution was used as extraction solvent, QuEChERS was used as purification method, acetonitrile-saturated n-hexane was used for degreasing, Waters ACQUITY UPLC BEH C₁₈ (2.1 mm×100 mm, 1.7 μm) column was used for gradient elution with acetonitrile-0.1% formic acid solution as mobile phase. The ionization mode was spray positive ion mode, and quantitative analysis was performed using multiple reaction monitoring mode. The quantitative method was external standard. Results The 24 kinds of β-blockers in eggs showed a good linear relationship (r≥0.9963) in the concentration range. When the sample weight was 1 g (accurate to 0.001 g) and the final volume was 2 mL, the limit of detection was 3 μg/kg, and the limit of quantitation was 10 μg/kg. The average recoveries were 63.6%-108.0%, and the relative standard deviations (n=6) were 0.9%-7.4%. Conclusion This method has the advantages of simple operation, high accuracy, high sensitivity and good reproducibility, and can provide technical reference for the analysis of β-blocker in fresh eggs in daily life and sports events.

Objective To establish an analytical method for the determination of 146 kinds of pesticide residues in animal derived foods by enhanced matrix removal-lipid dispersion solid phase extraction (dSPE EMR-Lipid) and purification technology coupled with gas chromatography-tandem mass spectrometry (GC-MS/MS). Methods The 5 g sample were added to 2 mL ultrapure water, extracted with acetonitrile, freezed for 10 min, separated with QuEChERS EN-extraction package, cleaned-up with dSPE EMR-Lipid, then was detected by GC-MS/MS in dynamic multi-reaction monitoring (DMRM) mode. The analytes were quantified by matrix-matched standard curve method. Results The results showed that 146 kinds of pesticides had good linearities in the concentration of 5-320 μg/L, the linear correlation coefficient of the compounds were greater than 0.9939, and the limits of detection of the method were 0.04-10.91 μg/kg, the limits of quantification were 0.11-32.72 μg/kg. The average recoveries of 146 kinds of pesticides at the spiked level of 0.01, 0.02 and 0.10 mg/kg ranged from 61.3% to 119.3%, relative standard deviations were 0.15%-16.02%. Conclusion The method is simple in pre-treatment, convenient in operation, rapid, sensitive and accurate in detection, can meet the simultaneous detection requirements for multiple pesticide residues. It is suitable for preliminary screening and quantitative detection of multiple pesticide residues in animal derived food.

Objective To establish a quantitative analysis of multi-components by single marker (QAMS) method for the simultaneous determination of 9 kinds of components in Andrographis paniculata. Method The relative calibration factors of andrographolide with forsythitin, oleanolic acid, caffeic acid, andrographolide, dehydrated andrographolide, andrographolide, deoxyandrographolide, dehydrated andrographolide half succinate and sodium bisulfite were established by ultra performance liquid chromatographolide-tandem mass spectrometry. The relative correction factor was used to calculate the content of each component, and the calculated results of QAMS method were compared with the measured values of external standard method. Results The relative correction factors showed good reproducibility, and there was no significant difference between the results obtained by the QAMS method and the external standard method. Conclusion The QAMS method is suitable for the simultaneous determination of 9 kinds of components in Andrographis paniculata, ensuring the reliability of quality.

Objective To develop a method for analysis of 20 kinds of macrolides and lincomasides in mutton by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Methods Samples were initially extracted with acetonitrile, and the supernatant was concentrated to near dryness. The residues were further extracted with 50% methanol, and the 2 extracts were combined and diluted with a weak alkaline buffer solution (pH 8.0). The mixture was then concentrated and purified using an HLB solid-phase extraction cartridge. A methanol/5 mmol/L ammonium acetate solution (1:1, V:V) was used for final dilution. Detection was performed in positive ion multiple reaction monitoring mode. A matrix-matched standard curve was prepared for quantification. Chromatographic and mass spectrometry parameters were optimized for the 20 kinds of target compounds, while the effects of different mobile phases, extraction solvents, and purification methods on extraction efficiency and purification quality were thoroughly investigated. Results The 20 kinds of macrolides and lincomasides demonstrated excellent linearity within their respective ranges, with correlation coefficients (r²) exceeding 0.999. Recoveries ranged from 64.7% to 94.2%, the relative standard deviation was between 3.8% and 11.0%. Conclusion The developed method is sensitive, accurate, and suitable for the simultaneous detection of 20 kinds of macrolides and lincomasides in mutton.

Objective To establish a method for the simultaneous determination and risk assessment of multi-class pesticide residues in Cucumis sativus L. and Malus pumila Mill. using QuEChERS-liquid chromatography-tandem mass spectrometry. Methods Fruit and vegetable samples were homogenized using acetonitrile as extraction solvent, sodium chloride and anhydrous sodium acetate as salting-out agent, and the supernatant was taken and purified by primary secondary amines (PSA), graphitized carbon black (GCB) and anhydrous magnesium sulfate reagent, and 7 kinds of pesticides were analyzed in 11 min using an Agilent Poroshell 120 EC-C₁₈ column with gradient elution. The potential health risks associated with the consumption of Cucumis sativus L. and Malus pumila Mill. were assessed by calculating the estimated daily intake the estimated dietary intake (EDI) and hazard quotient (HQ). Results The 7 kinds of pesticides exhibited satisfactory linearity within the range of 5‒500 μg/L, with correlation coefficients more than 0.99. The limits of detection were 0.5‒1.0 μg/kg and the limits of quantification were 2.0‒4.0 μg/kg. The average recoveries ranged from 71.0% to 118.8% at three different spiked levels, with the relative standard deviations ranging from 3.1% to 12.7%. Concurrently, the HQ values of individual pesticides evaluated from the acceptable daily intake (ADI) were found to be less than 1, and their risks were within acceptable limits. Conclusion The method exhibits high accuracy, precision, and sensitivity, and is suitable for the simultaneous determination of multi-class pesticide residues in fruit and vegetable samples. Furthermore, the risk assessment results of this study demonstrated that the health risk to individuals from pesticide residues in Cucumis sativus L. and Malus pumila Mill. is within acceptable limits.

Cyperue esculentust L. oil was a kind of high-quality edible oil rich in monounsaturated fatty acids, protein and other nutrients. This paper reviewed the main extraction technologies of Cyperue esculentust L. oil (supercritical CO₂ extraction, subcritical butane extraction, pressing, leaching, aqueous enzymatic extraction, aqueous extraction, ultrasonic-assisted extraction and microwave-assisted extraction) in recent years. By summarizing and analyzing the characteristics of different extraction technologies in practical operation and their effects on the basic physical and chemical properties, fatty acids, sterols, vitamin E and volatile compounds of Cyperue esculentust L. oil, it was suggested that the development of Cyperue esculentust L. oil in the future could focus on 3 aspects: Optimizing the key machinery and equipment of traditional oil extraction technologies (pressing, aqueous extration and leaching) to improve the quality of oil and reducing the production cost of new oil extraction technologies (aqueous enzymatic extraction, supercritical CO₂ extraction, ultrasonic-assisted extraction, subcritical butane extraction and microwave-assisted extraction) to increase the popularization feasibility, strengthening the cultivation of new varieties of Cyperue esculentust L. oil with high oleic acid and increasing the research and development of its functions, so as to be beneficial to the industrialization of Cyperue esculentust L. oil.

Objective To optimize the process of preparing low methoxy pectin-lentinan gel beads by combining low methoxy pectin and lentinan with calcium lactate, and characterize the structure of gel beads prepared under the optimal process conditions. Methods The effects of calcium lactate concentration, curing time, and curing temperature on the hardness of gel beads were investigated through single factor experiment and response surface methodology, and the structure of gel beads was characterized by Fourier transform infrared spectroscopy, texture analysis, rheological analysis and scanning electron microscopy. Results The optimum preparation process of low methoxy pectin-lentinan gel beads was determined by response surface methodology as calcium lactate concentration of 6.2%, curing time of 44 min, and curing temperature of 48 ℃. Under these conditions, the hardness of the gel beads was 35.60 gf. Compared with low methoxy pectin gel beads, low methoxy pectin-lentinan gel beads produced stronger hydrogen bond interaction, and their elasticity, cohesion, and dynamic modulus were improved. Conclusion Lentinan can effectively improve the mechanical properties and texture properties of low methoxy pectin gel beads, and this study will provide a reference for the improvement of pectin gel bead systems.

Objective To optimize the extraction process of Chaenomeles sinensis polyphenols and study their antioxidant activity. Methods The extraction process of Chaenomeles sinensis polyphenols was optimized through single factor and orthogonal experiments; the in vitro experiments were simultaneously conducted to investigate the total reducing ability, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging ability, and hydroxyl radical scavenging ability of Chaenomeles sinensis polyphenols. Results The optimal process for extracting polyphenols from Chaenomeles sinensis was: Ethanol volume fraction of 60%, solid-liquid ratio of 1:25 (g/mL), ultrasonic temperature of 55 ℃ and ultrasonic time of 90 min. Under these conditions, the polyphenol extraction amount was 2.22 mg/g; at a sample concentration of 1.0 mg/mL, the total reducing ability, DPPH radical scavenging rate and hydroxyl radical scavenging rate of Chaenomeles sinensis polyphenols were determined to be 2.41±0.02, 89.33%±0.24%, and 81.30%±1.27%, respectively, all higher than vitamin C at the same concentration (2.29±0.08, 86.05%±0.39%, 80.94%±0.41%), indicating that Chaenomeles sinensis polyphenols had good antioxidant activity and promising application prospects. Conclusion This study provides a reference for further research and application of polyphenols in Chaenomeles sinensis, offers new ideas for the diversified and high-value utilization of Chaenomeles sinensis resources, and provides theoretical basis for the deep processing of Chaenomeles sinensis resources and rational dietary selection.

Objective To systematically evaluate the differences in overall quality of rice from different regions in Liaoning Province. Methods Using 125 different rice varieties as research objects, the quality of rice from different regions in Liaoning Province was analyzed and comprehensively evaluated through physical and chemical testing methods, using correlation analysis (CA), principal component analysis (PCA), and hierarchical cluster analysis (HCA). Results The order of influence of different varieties and origins of rice on quality indicators was: Retention rate of germ grains>chalky grains rate>chalkiness>milled rice rate>brown rice rate>moisture> ash>protein>brown rice quality>fat>length-width ratio>fiber. Using stepwise regression analysis, the regression equation was obtained as follows: Brown rice rate=4.672×brown rice quality-0.104×chalky grains rate+0.141×chalkiness-0.860×length-width ratio-13.205. PCA extracted 4 principal components with a cumulative variance contribution rate of 80.046%, effectively elucidating all quality information characteristics. The results from HCA were consistent with those obtained from PCA, categorizing the 125 rice varieties into 3 major groups; through comprehensive assessment, the top 3 ranked varieties were identified as Yudao No.17 from Xiqing Village, Shiyuan Town, Dashiqiao City in Yingkou; Ichigo-hime from Zhangjia Village at Xinli Farm in Dawa County, Panjin; and Yanfeng No.47 from Gongxing Village in Tianshui Township, Panshan County, Panjin. Conclusion This study effectively highlights the differences in quality among various regional rices within Liaoning and provides a theoretical basis for breeding programs and product development related to rice germplasm.

Objective To develop artificial hypoglycemic rice with leafy grass as a nutritional supplement, optimize its formula, and analyze its inhibitory activity on α-glucosidase and sensory quality. Methods The orthogonal experimental design was used to optimize the formula parameters of artificial rice, with corn amylose and rice starch as the main raw materials and edible leaf grass powder as the functional additive. The inhibitory activity of α-glucosidase was detected by enzyme labeling instrument to evaluate the hypoglycemic effect the samples, and the food sensory analysis was carried out according to the sensory evaluation method. Results The water extract of edible leaf grass showed a high inhibitory rate on α-glucosidase with an inhibitory concentration (IC₅₀) value 1.189 mg/mL, which was close to the inhibitory effect of the positive control acarbose. The optimized formula for producing artificial rice from edible leaf grass performed excellently in sensory evaluation, with good flavor, texture and appearance. Conclusion Edible leaf grass has excellent nutritional value and potential hypoglycemic activity. The artificial hypoglycemic rice develops based on it not only meets the special needs of diabetes patients, but also provides a new choice for the health food market, and has broad application prospects.

Tricholoma matsutake is a high-quality edible wild fungi in China, rich in a variety of nutritional constituents. Research shows that Tricholoma matsutake contains Tricholoma matsutake polysaccharides, Tricholoma matsutake proteins, Tricholoma matsutake polyphenols, sugar alcohols and other nutrients, high nutritional value, delicious taste, with the promotion of intestinal peristalsis, antioxidant, activation of the immune system, anticancer, antihypertension, antidiabetic and other efficacy, is known as “King of Fungi”. The principal production regions of Tricholoma matsutake in China is divided into the southwest region, such as Sichuan Province, Yunnan Province and other places, as well as the northeastern region, such as Heilongjiang Province, Jilin Province. Due to the different genetic backgrounds and growth environments of different production areas, the types and content of nutrients contained in Tricholoma matsutake are also different. Tapping into the nutritional quality characteristics of local Tricholoma matsutake is the basis for developing local specialty Tricholoma matsutake industry and creating regional brands. This paper systematically summarized and compared the main nutritional characteristics of the Tricholoma matsutake produced in the main producing regions of China. In general, the total fat content of the matsutake mushrooms in the producing regions was lower and the protein content was higher, among which the amino acid and crude fiber contents were higher in the southwestern producing region, while the northeastern producing region had lower fat content and higher average protein content. This review will provide new ideas and theoretical basis for the development of specialty food and health food of Tricholoma matsutake in each production area in China.

Objective To develop a Dioscorea polystachya-based probiotic beverage and assess its shelf life. Methods Using Dioscorea polystachya as the raw material, pH, viable cell count, and sensory evaluation were selected as indicators to screen suitable fermentation strains. The fermentation process was optimized through orthogonal experiments. The changes in viable cell count, sensory quality, soluble solids, pH, and total phenolic content of the beverage were studied during 30 days of storage at different temperatures (4, 25, 35 °C). A shelf life model was established based on the Arrhenius equation and first-order kinetic reaction, which was then used to predict the shelf life of the Dioscorea polystachya probiotic beverage. Results Lactobacillus plantarum, Streptococcus thermophilus and Lactobacillus bulgaricus were selected as the fermentation strains, with a ratio of 1:2:2. The optimal fermentation conditions were 4.5% sucrose, 4% inoculum, 48 hours fermentation time, and a fermentation temperature of 33 °C. The beverage stored at 4 °C showed better stability. The chemical kinetics model predicted the shelf life of the Dioscorea polystachya probiotic beverage to be 37 days under 4 °C storage conditions. Conclusion By optimizing the fermentation process and establishing a shelf life prediction model, this study provides theoretical and technical support for the production and storage of Dioscorea polystachya probiotic beverages, which can maintain good quality for an extended period under low-temperature storage conditions.

Objective To establish a new method for simple identification of vitamin A (VA) and unsaturated fatty acids in natural cod liver oil. Methods The cod liver oil sample was saponified and injected into a high-performance liquid chromatography system to detect the content of VA. After saponification of cod liver oil and its excipients, injected them into a gas chromatography system to analyze the localization and percentage of linoleic acid, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), and distinguish fish oil from vegetable oil. Results Under the new method, the linear relationship of VA concentration was good within the range of 30.00-1500.00 IU/mL (r²=0.9999); the average recovery rate was 96.1%. The relative standard deviation of instrument precision was 0.18%, the relative standard deviation of method precision was 1.13%, and the relative standard deviation of intermediate precision was 0.98%. There was a significant difference in the content of fatty acids between vegetable oils, fish oil and cod liver oil. Cod liver oil and fish oil were rich in EPA and DHA, while linoleic acid was low. Corn oil, rapeseed oil and olive oil did not contain EPA and DHA, but they were rich in linoleic acid. Conclusion The detection method establish in this article is simple and accurate, and can be used for the determination of VA and unsaturated fatty acid content in cod liver oil, laying the foundation for the development of ideal quality standards.

Objective To establish a screening and quantitative method for illegally added anthraquinone- containing plant laxatives in weight-loss foods. Methods The anthraquinone glycosides in foods were hydrolyzed into anthraquinone aglycones by the acid hydrolysis extraction method, and 8 kinds of anthraquinone aglycones produced by hydrolysis were determined by ultra performance liquid chromatography-Q-trap-tandem mass spectrometry (UPLC-Q-trap-MS). Multiple reaction monitoring (MRM) was used as a probe for detection, and the enhanced product ion scan (EPI) mode was triggered through information dependent acquisition (IDA). External standard method was adopted for quantification. Results The limit of detection of physcion in weight-loss foods was 5.0 mg/kg, and the limit of quantification was 12.5 mg/kg, with a good linear relationship in the range of 0.25-5.00 μg/mL. The limits of detection of the other 7 kinds of anthraquinone aglycones were 1.0 mg/kg, and the limits of quantification were 2.5 mg/kg, and they had good linear relationships in the range of 0.05-1.00 μg/mL, with correlation coefficients r≥0.992. Spike recovery tests were carried out at three concentration levels of 2.5, 5.0 and 20.0 mg/kg (physcion at 12.5, 25.0 and 100.0 mg/kg), respectively. The average recovery rates of the 8 kinds of anthraquinone aglycones were 80.6%-102.0%, and the relative standard deviations (RSDs) were 2.35%-8.80% (n=6). Conclusion This method has the characteristics of simple operation, high sensitivity and high accuracy, and is suitable for the simultaneous rapid screening and accurate quantification of 8 kinds of anthraquinone aglycones.

In recent years, mycotoxin contamination in food has become an important food safety issue with global concern. Mycotoxins are a type of secondary metabolites produced by fungi with characteristics of high toxicity, difficult decomposition and chemical stability. It is of great significance to establish an efficient and safe mycotoxin detoxification technology applicable to food. Based onenzyme catalysis, the biological detoxification technology has the advantages of high substrate specificity, mild conditions, green environment, which can overcome the damage of traditional physical and chemical detoxification technology to the quality and nutritional value of food. Immobilized enzyme technology can improve the catalytic performance of enzymes, endow them with values such as stability, reusability, and high throughput, as well as overcome the limitations of biological enzymes in the application process. This article reviewed the application of immobilized enzyme technology in food mycotoxin removal, analyzed the deficiencies of the current immobilized enzyme technology applied in food detoxification and possible future research directions, with a view to providing research ideas for the construction of more efficient immobilized enzyme catalysts.

Objective To investigate the induced expression level and enzymatic properties of recombinant bacterial laccase and to improve the degradation efficiency of sulfadiazine antibiotics by bacterial laccase. Methods In this study, the effects of induction temperature, induction time, and concentration of isopropyl β-D-thiogalactopyranoside (IPTG) on enzyme expression were investigated by one-way experiments. The enzymatic properties of recombinant bacterial laccase were also investigated by both pH and temperature. Results The degradation of sulfadiazine by recombinant bacterial laccase at 24 h was 50%. The optimal conditions for the expression of recombinant bacterial laccase in Escherichia coli BL21 (DE3) were as follows: Induction temperature of 16 ℃, induction time of 16 h, and IPTG concentration of 0.2 mmol/L. The optimal pH was 3, and the stability was best at pH 7, with the enzyme activity reaching 150% in 6 h. The optimal temperature was 80 ℃, and the thermal stability was best at 70 ℃, with the enzyme activity increasing to 120% in 1 h. The half-life was about 6 h. Conclusion This study provides an experimental basis for the application of bacterial laccase in the degradation of sulfadiazine antibiotics and lays down a theoretical basis for the future study of its potential application in the industry.

Objective To develop a colorimetric analysis method based on nanozymes, rapidly evaluate the total antioxidant capacity of wild edible mushrooms (Auricularia cornea, Flammulina filiformis, and Pleurotus ostreatus) in Yangzhou. Methods Nano silver modified manganous oxide (Mn/Ag NPs) nanozyme was prepared by the hydrothermal method, and its microstructure was confirmed by various characterization methods. The total antioxidant capacity of 3 kinds of wild edible mushrooms were extracted using different solvents, and their total antioxidant capacity were evaluated by the colorimetric analysis method based on Mn/Ag NPs nanozyme. In addition, the evaluation results were verified using the commercial 2,2’-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) kit. Results The colorimetric analysis method based on Mn/Ag NPs nanozyme achieved the rapid evaluation of the total antioxidant capacity of wild edible mushrooms in Yangzhou. Total antioxidant activity was Pleurotus ostreatus>Flammulina filiformis>Auricularia cornea. Extraction efficiency of solvent was ultrapure water>mixed solvent>ethanol>ethyl acetate. Conclusion The colorimetric analysis method based on Mn/Ag NPs nanozyme can rapidly evaluate the total antioxidant capacity of wild edible mushrooms in Yangzhou.

Excessive intake of fat in human body is the main cause of obesity and cardiovascular and cerebrovascular diseases. With the gradual enhancement of national health awareness, people gradually pay attention to fat substitutes with low calorie and low energy. Fat substitutes can not only meet people's sensory needs for color, fragrance and taste of food, but also reduce the intake of fat without changing the taste quality of food, which is of great significance to prevent various chronic diseases. Therefore, producing low-fat or fat-free food is an important way to improve people's eating habits and improve people's health. Fat substitutes are a kind of substances that mimic the fat in natural foods, which can be divided into 3 types: Fat substitutes (esterified derivatives of fatty acids, with almost zero digestibility in human body), fat simulators (carbohydrate fat simulators and protein fat simulators) and compound fat simulators. Fat substitutes can reduce the fat content in food, and more importantly, they can improve the oral sensory lubrication texture of food. This paper summarized the application and development prospect of fat substitutes in modern food research at home and abroad, in order to provide guidance for the research and development of low-calorie diet.

Objective To study the nutritional components of Weiying watermelon foranalyze and evaluate the nutritional quality of Weiying watermelon. Methods Namely “Meidu” watermelon from 2 main production areas of Weiying watermelon (S1 and S2) were used as experimental materials, and the same variety of watermelon from two other production areas (S3 and S4) as controls. The content of sugar, organic acid, amino acid, mineral, soluble solid, β-carotene, lycopene and vitamin C in the watermelons from the 4 production areas were detected and analyzed. Results The watermelon from different producing areas exhibited certain variations in quality characteristics. The sugar components in watermelon was mainly glucose and fructose, organic acids was mainly malic acid and lemon, free amino acids was mainly citrulline, and it also contains abundant mineral elements; the glucose content, sugar-acid ratio and sweetness-sourness ratio in S1 and S2 were higher than those in S3 and S4, while the total acid content was the opposite. In addition, the levels of the citrulline, β-carotene, lycopene and vitamin C in S1 and S2 were also higher than those in S3 and S4, respectively. The comprehensive performance of the nutritional quality of S1 and S2 were superior to that of S3 and S4 based on the principal component analysis. Conclusion Weiying watermelon has better flavor and texture, richer nutritional components, and superior nutritional quality.

Objective To isolate a strain of Listeria monocytogenes from frozen chicken meat sold in Gansu Province and analyze its serotype, antibiotic resistance phenotype, and genomic characteristics. Methods The slide agglutination method was used for serological identification, the broth microdilution method was used to analyze the sensitivity of the strain to 8 kinds of antibiotics, and the genomic characteristics were analyzed by sequencing. Results The strain was identified as Listeria monocytogenes by 16S rDNA species identification, with a 1/2a serotype, phylogenetic lineage II, subline SL 155, and clone CC 155 MLST 705, cgMLST 13240. Sensitive to 4 kinds of antibiotics including ampicillin, penicillin, vancomycin, and meropenem, and multidrug-resistant to 4 kinds of antibiotics including erythromycin, ciprofloxacin, tetracycline, and compound sulfamethoxazole. Simultaneously carrying aph(3')-III, ant(6)-Ia, dfrG, fosX, lnu(B), lsa(E), erm(B), tet(S) and tet(M) 9 kinds of resistance genes, carrying 5 virulence genes of LIPI-1, prfA gene deletion, carrying 12 kinds of internalization genes, no premature stop codon of inlA gene carrying, no LIPI-3, and LIPI-4. Conclusions The Listeria monocytogenes carries abundant virulence genes and resistance genes, and its resistance phenotype is basically consistent with the resistance genes, showing multiple drug resistance, providing a reference for the prevention and treatment of listeriosis.

Objective To elucidate the effects of flower of Changshan-huyou on the aroma profile of black tea. Methods This study employed solid phase microextraction-gas chromatography-tandem mass spectrometry (SPME-GC-MS) to differentially analyze the aroma components of flower of Changshan-huyou, Jiukeng black tea, and the derived Changshan-huyou scented tea. Results A total of 186 volatile compounds were identified in this paper, with 92, 78 and 67 kinds of volatile compounds detected in flower of Changshan-huyou, Jiukeng black tea and Changshan-huyou scented tea, respectively. The volatile composition of flower of Changshan-huyou was mainly characterised by alcohols and alkenes, whereas the volatile profiles of Jiukeng black tea and Changshan-huyou scented tea were mainly alcohol-rich. Nerolidol and linalool were found to be the predominant aroma components in Changshan-huyou scented tea, imparting a pronounced flora, fruity aroma and sweetness. Comparative analysis revealed an increase in alcohols and a concomitant decrease in alkenes in Changshan-huyou scented tea compared to flower of Changshan-huyou. Conversely, an increase in alkenes and a decrease in aldehydes were observed in Changshan-huyou scented tea compared to Jiukeng black tea. In addition, 32 kinds of unique compounds were identified in Changshan-huyou scented tea, which may be due to its unique processing techniques and the specific varieties of raw materials used. Conclusion The results of this research not only substantiate the aroma signature of Changshan-huyou scented tea, but also provide insights into its quality enhancement, paving the way for standardised production and innovative development strategies.

Objective To analyse the types and content of metabolites in the stems and leaves of Platycodon grandiflorus by ultra performance liquid chromatography-Quadrupole/Orbitrap high-resolution mass spectrometry (UPLC-Q/Orbitrap HRMS). Methods Stems and leaves of two-year-old purple flowered Platycodon grandiflorus from different sources was used as experimental materials. UPLC-Q/Orbitrap HRMS technology was used to analyze the extracts of Platycodon grandiflorus stems and leaves in negative ion mode, using orbitrap for MS1 full scan and data dependent acquisition ion trap for MS2 scan, and screen for differential metabolites of Platycodon grandiflorum stems and leaves from different sources. Results A total of 18 metabolites were detected in the stems and leaves of Platycodon grandiflorum, including 4 flavonoids, 2 alkynyl glycosides, and 12 saponins (1 metabolite that had not been reported). The basic structure of this unknown compound was polygalacic acid-glucose- xylose/arabic glycoside. Through comparative analysis, differences in chemical composition of Platycodon grandiflorus among different sources were discovered. The 6 differential metabolites of Platycodon grandiflorus from China and South Korea and 1 differential metabolite of Platycodon grandiflorus from Yanbian area were screened. Conclusion The comprehensive analysis results indicate that the stems and leaves of Platycodon grandiflorus have rich chemical components, and the stems and leaves of Platycodon grandiflorus from different sources have compound differences, which have high development and utilization prospects, providing theoretical basis for the development and utilization of aboveground resources of Platycodon grandiflorus.

Objective To investigate the feasibility of using the adenosine triphosphate (ATP) bioluminescence method for detecting the colonies number in chilled meat, and compare its performance with the national standard plate count method. Methods Effects of different concentrations of Triton X-100 and adenosine triphosphate double (Apyrase) on the remove of ATP from the somatic cells of chilled meat were determined. The colonies number in the chilled meat was measured using both the ATP bioluminescence method and the national standard plate count method, and the reproducibility of the ATP bioluminescence method was evaluated. Results The optimal concentrations of Triton X-100 and Apyrase for ATP removal from the somatic cells of chilled meat were found to be 0.2% and 0.10 U/mL, respectively, with the best ATP removal effect observed at these concentrations. The results of the ATP bioluminescence method and the national standard plate count method demonstrated a strong linear relationship, with a correlation coefficient (r²) of 0.9871. The ATP bioluminescence method indicated good reproducibility, and the results were stable and reliable. Conclusion This study further validates the applicability of ATP bioluminescence method for the quick detection of colonies number in chilled meat, demonstrating its advantages over the national standard plate count method.

Objective To establish a method for the determination of chlorophyll a and chlorophyll b content in vegetables by convergence chromatography (CC). Methods The Soxhlet extraction method was used for efficient extraction of chlorophyll from vegetables and their products, followed by separation and detection using an ultra-performance convergence chromatography system coupled with a ultraviolet-visible detector. Results Through comparison of the stability of different solvents, petroleum ether was selected as the extraction solvent, and the extraction conditions were optimized. The method was validated with a limit of detection of 0.02 mg/kg, a limit of quantification of 0.06 mg/kg, a linear range of 0.06-800.00 mg/kg, a spike recovery rate of 99%-102%, and a relative standard deviation of 2.2%-14.0% for real samples. The reliability and accuracy of the method were confirmed through precision testing of real samples, including kale, fresh mustard greens, pickled mustard greens, dried pickled mustard greens, steamed dried pickled mustard greens, and boiled dried pickled mustard greens, as well as cross-validation with existing standard methods. Conclusion This study establishes a CC-based method for detecting chlorophyll a and chlorophyll b in vegetables, demonstrating high sensitivity, a wide linear range, good specificity, and precision. The method is not only suitable for laboratory research but also has practical application potential.

Objective To establish an efficient method for assessing the authenticity of Citrus reticulata Blanco honey. Methods High performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was utilized for the qualitative and quantitative analysis of plant compounds present in Citrus reticulata Blanco honey. The authenticity of commercially available Citrus reticulata Blanco honey was evaluated by integrating characteristic components with HPLC fingerprints. Results A total of 6 kinds of components were identified in Citrus reticulata Blanco honey, namely caffeine, cis,trans-abscisic acid, 5-methoxybrevosin, pinocembrin, kaempferol and chrysin. Caffeine exhibited a relatively high concentration, with an average content of 9.45 mg/kg. Thus, it was regarded as a characteristic component of Citrus reticulata Blanco honey. The authenticity assessment of 6 kinds of Citrus reticulata Blanco honeys available on the market revealed that 4 brands exhibited superior quality, one brand might be adulterated with other components, and one brand could potentially be counterfeit Citrus reticulata Blanco honey. Conclusion This study presents a novel methodology that synergistically combines characteristic component profiling with HPLC-fingerprinting technology for authenticity assessment of Citrus reticulata Blanco honey. This study provides a theoretical foundation for grading Citrus reticulata Blanco honey and enhancing its added value.

Objective To investigate the prevalence, virulence phenotypes, and drug resistance phenotype of Vibrio parahaemolyticus in freshwater food, seafood, and ready-to-eat food in Yangzhou. Methods Freshwater food, seafood and ready-to-eat food samples were collected from 9 sampling points in Yangzhou markets for isolation and identification of Vibrio parahaemolyticus. The motility, hemolytic activity, and drug resistance phenotype of the isolates were analyzed. Results In 2023, a total of 289 samples were collected in the Yangzhou market, from which 63 strains of Vibrio parahaemolyticus were isolated, with an isolation rate of 21.80%. Among them, the isolation rate of freshwater food was 45.35% (39/86), seafood 28.75% (23/80), and ready-to-eat samples 0.81% (1/123), indicating a higher isolation rate in freshwater food compared to seafood in the markets of Yangzhou. The proportion of highly motility strains in freshwater food isolates was 30.77%, higher than that of the seafood isolates (17.39%). However, the proportion of strains with high hemolytic activity was 53.85% in freshwater food isolates, slightly lower than the 60.87% in seafood isolates. Antibiotic resistance profiling showed that all Vibrio parahaemolyticus isolates were resistant to ampicillin and cefazolin, while they were resistant to ceftazidime, tetracycline, ciprofloxacin, chloramphenicol, amikacin, meropenem and gentamicin. Conclusion This study highlights a high detection rate of Vibrio parahaemolyticus in Yangzhou markets and reveals differences in virulence and antibiotic resistance among isolates from different sources, offering valuable insights for monitoring and controlling the pathogen.

Objective To compare the taste characteristics, physical and chemical indicators of preserved mustards samples in market, and statistically analyze the correlation between taste quality and physical and chemical indicators. Methods The 22 samples of preserved mustards from Zhejiang, Sichuan and Hunan were collected, and the taste characteristics of preserved mustards were analyzed by artificial sensory evaluation and electronic tongue, the physical and chemical indicators such as moisture content, total acid, amino acid nitrogen, trichloroacetic acid (TCA) soluble peptides, nitrite, and reducing sugar content were analyzed. Results The saltiness and umami of preserved mustards were prominent, and the acidity intensity of different preserved mustards varied greatly. Umami was significantly negatively correlated with sourness and saltiness (P<0.01), and significantly negatively correlated with bitter aftertaste (P<0.05). Water content had a great influence on the taste quality of preserved mustards, and was significantly positively correlated with the taste (P<0.05). The salt content was significantly negatively correlated with the total acid content (P<0.01). Conclusion The taste characteristics and physical and chemical indexes of different preserved mustards samples are very different, and some preserved mustards have high salt content, so it is necessary to establish quality standards; the taste quality and physical and chemical indexes of preserved mustards from different origins does not show obvious regional characteristics; there is a negative correlation between the indexes of carbohydrate fermentation products and protein fermentation products in preserved mustards.