To investigate the effect of moderate enzymatic hydrolysis process on the quality of walnut milk.

Walnut milk was treated with flavor protease and alkaline protease (the ratio was 2:1) under different enzymatic hydrolysis times: Blank control (no enzyme), 0 min (enzyme added and immediately inactivated), 30 min, 60 min and 120 min. The nutritional components, physical stability, aroma components and sensory quality of walnut milk were systematically analyzed.

The nutritional components of walnut milk treated under different enzymatic hydrolysis times were different. With the increase of enzymatic hydrolysis time, the content of oligopeptides and free amino acids in the samples increased, reaching the highest levels at 120 min. The stability kinetic index of walnut milk after enzymatic hydrolysis for 30 min was the lowest and the stability was better.Enzymatic hydrolysis improved the aroma characteristics of walnut milk, increasing both the diversity and abundance of volatile compounds. Sensory evaluation showed that enzymatic hydrolysis enhanced the aroma intensity of walnut milk and the mouthfeel became smoother and more delicate, with the 30 min hydrolysate receiving the best overall acceptability.

Enzymatic hydrolysis for 30 min is the optimal time that provides the best overall balance for walnut milk. At this time, the nutritional composition, stability, flavor and sensory quality of walnut milk are improved.

To utilize the nutritional composition of the meat and the mineral element composition of the shells of the Sinonovacula constricta to construct a reliable model for discriminating the origin and farming mode of the species.

The 4 major production areas in Zhejiang Province, namely Linhai, Sanmen, Ninghai(pond farming) and Xiangshan (mudflat farming), were selected as the research subjects. The quality indicators of the Sinonovacula constricta, including appearance traits, nutritional composition, amino acid composition, fatty acid composition and mineral element content, were systematically analyzed. Principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA) and variable importance in the projection (VIP) were used to screen out the key characteristic parameters that affect the discrimination of the origin of the Sinonovacula constricta, and a discrimination model for different origins of the Sinonovacula constricta was constructed.

The quality analysis indicated that there were significant differences in the characteristics of the Sinonovacula constricta from different production areas and farming modes: The amino acid content (49.88 g/100 g) and the proportion of polyunsaturated fatty acids (41.46%) of the Sanmen (pond farming) Sinonovacula constricta were the highest; the content of trace elements in the Ninghai (pond farming) Sinonovacula constricta was relatively high; and the content of multiple nutritional indicators in the Xiangshan (mudflat farming) Sinonovacula constricta was relatively low.PCA, PLS-DA and VIP screened out 19 key characteristic parameters, including 5 kinds of minerals (iron, manganese, copper, calcium and zinc) in the soft tissue of the Sinonovacula constricta, 8 kinds of fatty acids(eicosapentaenoic acid, docosahexaenoic acid, etc.), and alanine; and 5 kinds of minerals (sodium, manganese, selenium, magnesium and calcium) in the shell. The constructed PLS-DA model had a good fit. The samples from pond farming and mudflat farming were clearly distinguished in the latent variable space; at the same time, the samples from the 3 adjacent pond farming production areas (Linhai, Sanmen and Ninghai) also showed independent clustering trends, indicating that the model could effectively capture the chemical fingerprint differences shaped by both the origin and the farming mode.

This study screens out 19 key characteristic parameters for the discrimination of the origin of the Sinonovacula constricta and constructed a discrimination model that can effectively distinguish the Sinonovacula constricta from different origins and farming modes (pond and mudflat)within Zhejiang Province. The model not only overcame the interference caused by the difference in farming modes but also accurately discriminate the Xiangshan (mudflat) production area, and shows good discrimination ability for the 3 adjacent pond farming production areas (Linhai, Sanmen and Ninghai). This provides a reliable technical means for the origin traceability of the Sinonovacula constricta under complex farming backgrounds.

To investigate the effects of 4 kinds of primary processing methods—freeze-drying, washing, sun-drying and honey processing—on the composition and content of free amino acids in Ruili arabica coffee beans.

The composition and content of free amino acids in coffee bean samples were determined using a fully automatic amino acid analyzer. Characteristic taste-related amino acids in coffee beans were screened and analyzed through principal component analysis (PCA) and orthogonal partial least squares discriminant analysis(OPLS-DA).

The 17 kinds of free amino acids were detected in all 4 groups of coffee bean samples with different initial processing treatments, but their content, compositional distributions and proportions varied. The honey-processed coffee beans exhibited the highest total free amino acid content at 10.236 mg/g, followed by the freeze-dried group with 10.144 mg/g, while the washed group showed the lowest content of 9.823 mg/g. Among them, the honey-processed group exhibited the highest total content of sweet and bitter amino acids, while the freeze-dried group showed the highest total content of umami amino acids. The washed group had the lowest total content of both sweet and bitter amino acids, and the sun-dried group demonstrated a relatively low total content of umami amino acids. The screening analysis through PCA and OPLS-DA revealed that in coffee bean samples subjected to 4 kinds of different processing methods (freeze-drying, washing, sun-drying and honey processing), glutamic acid, tyrosine, threonine and arginine were identified as the key characteristic flavor amino acids respectively.

Different primary processing methods have a significant impact on the free amino acid content of Ruili arabica coffee. The research results provide a scientific basis for the coffee industry to optimize the primary processing technology and improve coffee quality.

To establish a fingerprint similarity evaluation method suitable for Chinese sauce-flavor Baijiu.

The 50 batches of A2 Chinese sauce-flavor Baijiu were determined by gas chromatography, and then the gas chromatography fingerprint of A2 was constructed. Similarity evaluation methods of 6 kinds of fingerprint spectra were established, and the similarity threshold was verified by different quality of Chinese sauce-flavor Baijiu.

The correlation coefficient method, vectorial angle method, information entropy method and the Euclidean distance method could not correctly distinguish different quality liquor bodies. The accuracy rate of weight non-uniformity similarity in judging different wine bodies was 100%, which was consistent with the sensory evaluation judgment results of wine bodies.

The similarity of weight non-uniformity is suitable for the data evaluation of fingerprint spectra of sauce-flavored Baijiu. This study provides a new method for the quality control of Chinese sauce-flavored Baijiu.

To explore the effects of different modified atmosphere packaging on the freshness and microbial community structure changes of chilled beef during storage.

This study established 4 treatment groups: Modified atmosphere packaging group 1 (LAR) (20% O₂, 10% N₂, 70% CO₂+absorbent pad), modified atmosphere packaging group 2 (ARAB) (20% O₂, 10% N₂, 70% CO₂+self-made antibacterial absorbent pad), modified atmosphere packaging group 3 (MAR) (45% O₂, 10% N₂, 45% CO₂+absorbent pad), and modified atmosphere packaging group 4 (HAR) (60% O₂, 20% N₂, 20% CO₂+absorbent pad). The 4 kinds of different types of chilled beef in modified atmosphere packaging were stored at 4 ℃ for 10 days. The sensory properties, pH, total volatile basic nitrogen (TVB-N), thiobarbituric acid reactive substances (TBARs), drip loss rate and total viable count of the chilled beef during the storage period were regularly measured, and the changes in the microbial community structure were analyzed simultaneously.

During the 10 d storage period, all the samples treated with modified atmosphere packaging remained at the first grade of freshness, and the TBARs did not exceed the standard limit. On the 10th day of storage, all the samples showed unacceptable conditions such as unpleasant odors. The total number of colonies increased to varying degrees from 0 to 6 days and then tended to stabilize. TVB-N did not exceed the limit (15 mg/100 g) within the 6-day storage period. The drip loss rate increased in all groups during the storage period, with the MAR group showing the smallest rate of change. At the beginning of storage, the dominant phyla in all modified atmosphere packaging treatment groups were Firmicutes, Actinobacteriota, Proteobacteria and Bacteroidota. As the storage time increased, the dominant phyla also changed. In the high oxygen content treatment group HAR, the dominant phyla were Firmicutes and Proteobacteria, while in the other groups, they were all Firmicutes. At the genus level, the dominant genera in the HAR treatment group were Leuconostoc, Lactobacillus, Lactococcus, Serratia and Pseudomonas, while in the other treatment groups, the dominant genera were Leuconostoc, Lactobacillus and Lactococcus.

In this study, different modified atmosphere packaging has certain effects on the freshness and microbial community of chilled beef during storage. It is worth noting that the dominant bacterial genera in the LAR, ARAB and MAR groups are all lactic acid bacteria, while in the HAR group with an oxygen content of 60%, the dominant bacterial genera are Pseudomonas, Serratia and other genera.

To evaluate the taste and nutritional quality of Songjiang rice by multivariate statistical methods.

This study focused on 2 varieties of Songjiang rice and 3 kinds of other types of rice from distinct geographical origins. Quality indicators including moisture, protein, fat, amylose content, gel consistency, calcium, iron, zinc and selenium were analyzed. Coefficient of variation analysis, correlation analysis, principal component analysis and cluster analysis were employed for a comprehensive evaluation of the rice’s taste and nutritional quality.

The coefficients of variation for quality indicators of the rice ranged from 5.24% to 49.90%. Among these indices, selenium content displayed the greatest variability, while moisture content exhibited the least. Correlation analysis revealed that amylose content showed a significantly, moderately strong negative correlation with gel consistency. Meanwhile, calcium and iron were significantly and moderately strong positive correlated, as were zinc and protein (P<0.05, correlation coefficient |r|>0.5), indicating information overlap among the quality indicators. Principal component analysis reduced 9 indicators into 3 independent principal components, which together accounted for 71.04% of the cumulative variance. The comprehensive scores for taste and nutritional quality were ranked in descending order as follows: Songxiangjing 1013, Chongming rice, Songxiangjing 1018, Sheyang rice and Wuchang rice. Among these, the Songxiangjing 1013 rice showed outstanding overall quality performance.

The study effectively demonstrates the variations in taste and nutritional quality of rice from different producing regions and different varieties. It establishes a data foundation for the quality evaluation of Songjiang rice and provides theoretical references for rice variety selection, promotion and regional cultivation planning.

To comprehensively evaluate the nutritional value of Juglans regia L. in different regions of Xinjiang.

Using a fully automatic amino acid analyzer, the ninhydrin post-column derivatization ion-exchange chromatography method was employed at wavelengths of 570 nm and 440 nm. By comparing with the amino acid pattern spectra of the United Nations Food and Agriculture Organization/World Health Organization(FAO/WHO) and the ideal protein standards, the ratios of essential amino acids (RAA) and the ratio coefficients of essential amino acids (RC) were calculated. The nutritional value of amino acid content in Juglans regia L. kernels was evaluated.

The 44 Juglans regia L. samples from different locations in 3 regions of Xinjiang all contained 17 kinds of amino acids, among which glutamic acid, lysine and arginine had relatively high content, and the proportion of essential amino acids was 0.32. The amino acid composition of Juglans regia L. from different regions varied greatly, and the amino acid ratio of walnuts from Kashgar region was better than that of other regions.Through the comparison and analysis of the FAO/WHO amino acid pattern spectrum, lysine and threonine were the main limiting amino acids. The score of ratio coefficient (SRC) value of the Zha 343 variety Juglans regia L. was the highest, and the defect degree of the first limiting amino acid was the lightest. Its RC value (chemical score) of lysine was 0.761. The amino acid supply and demand balance was the best, and there was no extremely excessive amino acid in this variety. The total RC value of phenylalanine and tyrosine was 1.406.

Based on the comprehensive amino acid evaluation indicators, the comprehensive nutritional quality of Zha 343 Juglans regia L. in Kashgar, Xinjiang is superior. This study provides a scientific basis for the analysis of nutritional components and processing utilization of Juglans regia L., and offers theoretical support for enhancing the market value of Xinjiang Juglans regia L.and promoting their application.

To investigated the effects of low-temperature plasma treatment on the quality characteristics of Triticum aestivum L. flour.

In this study, wheat flour was treated with atmospheric pressure low-temperature plasma at different times and power levels. The variation patterns of its quality indicators were systematically analyzed.

When the treatment power was below 200 W, the starch damage content and protein content were minimally affected, whereas the total free amino acids were highly sensitive to the low-temperature plasma treatment, decreasing by 90.1% under the conditions of 200 W for 20 minutes.Simultaneously, the fatty acid content dropped by 28.6%, and the gluten index decreased by 16.4%. However, under the conditions of 120 W for 10 minutes, the gluten index increased to 97.4%, indicating that moderate plasma treatment could improve the gluten network structure. In addition, the setback values of all treatment groups increased significantly (P<0.05, increase of 17.7%-49.7%), and the amylase activity decreased significantly (P<0.05).

The influence of low-temperature plasma treatment on the quality of wheat flour is indicator-specific.This study provides a basis for regulating the adaptability of wheat flour processing and the precise application of this technology.

To optimize the processing of Chaenomeles speciosa leaf beverage using fuzzy sensory evaluation and response surface methodology, and investigate its shelf life and antioxidant activity.

Using sensory scores as the key indicator, the formulation was optimized by fuzzy mathematics sensory evaluation combined with single-factor analysis and response surface methodology. The flavor profile was characterized by headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry, electronic nose, and electronic tongue bionic systems. Furthermore, the beverage’s shelf life was predicted based on a chemical reaction kinetics model incorporating the Arrhenius equation.

The optimal formulation of beverage was 60 mL extract solution, 2 g sweetener and 0.01 g DL-malic acid, achieving a sensory score of 88 points. The beverage exhibited a rich flavor, bright color and a taste profile of initial sweetness followed by bitterness. A total of 19 kinds of volatile aroma compounds were identified, predominantly aromatic compounds. The product exhibited good stability, with a shelf life of 189, 146 and 128 days at 4, 25 and 37 °C. respectively, the antioxidant capacity remained stable during the storage period.

The beverage has good flavor and antioxidant activity, this study provides an effective solution for the value-added utilization of by-products in the Chaenomeles speciosa industry, contributing to the enhancement of the industry’s overall value.

To establish a rapid detection method for the residue of the fungicide hexaconazole in food by dispersive liquid-liquid microextraction-high performance liquid chromatography.

A deep eutectic solvent synthesized from fenchyl alcohol, hexanoic acid and acetic acid at a molar ratio of 1:3:4 was used as the supporting solvent to prepare a ferrofluid with self-dispersibility and magnetic responsiveness by incorporating Fe₃O₄ nanoparticles. The prepared ferrofluid served as the extraction solvent for dispersive liquid–liquid microextraction, and hexaconazole was subsequently separated and quantified by high-performance liquid chromatography.

Under the optimal experimental conditions, the detection linear range of this method for hexaconazole was 0.02–2.00 μg/mL, the limit of detection was 0.006 μg/mL, and the relative standard deviation was less than or equal to 8.2%. The recovery rates of samples added to mineral water, tea and fruit juice were 83.9% to 95.6%.

This method is environmental friendly, easy to operate and highly sensitive. It can be effectively applied to the rapid detection of pesticide residues in food, providing a new and effective technical means for food safety testing.

To establish a rapid detection method suitable for the determination of chlorpyrifos residues in vegetables based on the colloidal gold immunochromatographic technology.

The pretreatment conditions such as extraction solvent, extraction time and detection temperature were systematically optimized to determine the optimal rapid detection parameters. Additionally, the performance indicators of this rapid detection method, including false negative rate, false positive rate and relative accuracy, were confirmed.

Using 8.0 mL of 0.1 mol/L phosphate buffer saline solution as the sample extraction solvent, setting the extraction time to 3 min, and controlling the detection temperature within the range of 15–35 ℃ were determined as the optimal parameters for rapid detection. The experimental results showed that the false negative rate and false positive rate of this method were both 0%, with a relative accuracy of 100%; the rapid detection results of 20 vegetable samples were consistent with those obtained by the liquid chromatography-tandem mass spectrometry method.

This method demonstrates excellent detection performance and is suitable for on-site rapid detection and large-scale screening of chlorpyrifos residues in vegetables.

To establish a method for the simultaneous determination of 7 kinds of veterinary drug residues, including ciprofloxacin, enrofloxacin, ofloxacin (3 kinds of fluoroquinolones), chloramphenicol, thiamphenicol, flufenicol (3 kinds of amphenicols) and isometamidium (1 kind of antitrypanosomal drugs) in milk by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS).

Milk samples were extracted by the mixture of acetonitrile and 0.5 mmol/L ammonium formate in methanol (1:1, V:V), purified by n-hexane, dried by nitrogen. The 7 kinds of veterinary drug residues in milk samples were detected by UPLC-MS/MS and quantified by matrix matching external standard method.

The linear range of 7 kinds of veterinary drugs in milk was 1.0–200.0 µg/L with good linearity (r² were all greater than 0.993). The limits of detection were 0.08–0.44 µg/kg, and the limits of quantitation were 0.28–1.46 µg/kg. Milk matrix had an enhanced matrix effect on all 7 kinds of veterinary drugs. The recoveries of 7 kinds of veterinary drugs at low, medium and high concentrations were 47.44%–117.89%, 82.34%–112.84%, 73.15%–117.69%, respectively. The relative standard deviations were 1.46%–8.26%. This method was used to analyze 9 samples of commercially available milk, and no residues of 7 kinds of veterinary drugs were detected in any of them.

This method is highly sensitive and easy to operate, and can meet the rapid and accurate detection requirements of seven kinds of veterinary drugs in milk.

To establish a method for the determination of 6 kinds of quinolone residues (ofloxacin, norfloxacin, lomefloxacin, pefloxacin, enrofloxacin and ciprofloxacin) in eggs by solid-phase extraction combined with liquid chromatography-tandem triple quadrupole mass spectrometry.

Egg samples were extracted with 0.1 mol/L ethylenediaminetetraacetic acid-Mcllvaine (EDTA-Mcllvaine) buffer, purified by HLB solid-phase extraction cartridges and separated on an Acquity BEH C₁₈ column (100 mm×2.1 mm, 1.7 μm) using a gradient elution with methanol-acetonitrile (4:6, V:V) and 0.2% formic acid aqueous solution as the mobile phase. The analytes were detected in positive electrospray ionization (ESI+) mode with multiple reaction monitoring (MRM), quantified using a matrix-matched calibration curve.

The 6 kinds of quinolones exhibited good linearity in the range of 1.0–100.0 μg/kg with correlation coefficients (r²) more than 0.999. The limits of detection and limits of quantitation were 0.13–0.25 μg/kg and 0.43–0.83 μg/kg, respectively. The average recoveries ranged from 94.6% to 108.0%, with relative standard deviations of 2.48%–6.34% (n=3).

The developed method is simple, sensitive and robust, suitable for the rapid detection of quinolone residues in eggs, providing technical support for food safety monitoring.

To clarify the residue characteristics of the novel acaricides cyetpyrafen in different parts of Malus domestica.

Field trials were conducted in accordance with the Guidelines for pesticide residue trials in crops. The 30% cyetpyrafen suspension was used as the test object, and the early-maturing Malus domestica variety Honglu was used as the test material. The whole Malus domestica trees were sprayed with the recommended dose and twice the recommended dose during the occurrence period of Malus domestica mites and before fruit harvest. Samples were randomly collected after spraying. The residues of cyetpyrafen in different parts of Malus domestica at different doses were determined by QuEChERS-high performance liquid chromatography.

Within the mass concentration range of 0.05–5.00 mg/L, the mass concentration of cyetpyrafen in the Malus domestica matrix had a good linear relationship with the response value, and the correlation coefficient was greater than 0.99. In the addition recovery test, the average recovery rate of cyetpyrafen was 98.88%–100.22%(relative standard deviation was 0.34%–0.92%). The detection results showed that the residues of cyetpyrafen mainly adhered to the Malus domestica peel, and the residues conducted to the flesh through internal absorption were very few. The average residue amount showed the trend of peel>whole fruit>flesh. Under the recommended dosage, the residue level in the fruit peel was the highest, reaching 3.19 mg/kg 2 h after application, which was over 3 times the maximum residue limit (MRL) (1 mg/kg). The residue level in the fruit peel dropped to 0.6 mg/kg 5 d after application, below the MRL (1.00 mg/kg), indicating a relatively low safety risk. At twice the recommended dose, the original residue amount in the peel 2 h after spraying was 5.90 mg/kg, which was 1.85 times that of the recommended dose. At twice the recommended dose, the residue amount in the peel 7 d after spraying was 1.11 mg/kg>1.00 mg/kg(MRL), still not meeting the standard.

The Malus domestica peel is the main residue site of etofenprox.The residue amount increases significantly with the increase of the application dose. Applying at doses exceeding the recommended level will significantly increase the residue risk and directly affect the food safety of Malus domestica.It is recommended that during production, the recommended dosage should be strictly followed for application, and the frequency of application should be controlled. It is suggested that a harvest interval of more than 7 d. Consumers can effectively reduce potential risks by peeling the fruit.

To establish a method for the simultaneous determination of dexamethasone, betamethasone, florfenicol and florfenicol amine residues in pork and beef by high performance liquid chromatography-tandem mass spectrometry.

The samples were extracted with acetonitrile and purified using the QuEChERS method. Separation was performed on a BEH-C₁₈ column with acetonitrile and ultrapure water as the mobile phase for gradient elution. Qualitative and quantitative analysis was conducted via multiple reaction monitoring under both positive and negative ion scanning modes using the external standard method.

Dexamethasone, betamethasone, florfenicol and florfenicol amine exhibited excellent linearity within the mass concentration range of 0.2–100.0 ng/mL, with correlation coefficients exceeding 0.9990. The recovery rates ranged from 85.1% to 107.5%. The limits of detection (LODs) for dexamethasone were 0.44–0.48 μg/kg and the limits of quantitation (LOQs) were 1.45–1.58 μg/kg. For betamethasone, the LODs were 0.46–0.51 μg/kg and the LOQs were 1.52–1.68 μg/kg. For florfenicol, the LODs were 0.47–0.58 μg/kg and LOQs were 1.55–1.91 μg/kg. For florfenicol amine, the LODs were 0.40–0.45 μg/kg and the LOQs were 1.32–1.49 μg/kg.

This method demonstrates accurate parameter determination, with excellent recovery rates, high precision, and a simple, convenient pretreatment process. It meets the requirements for simultaneous screening and qualitative and quantitative detection of dexamethasone, betamethasone, florfenicol and florfenicol amine residues in pork and beef, thereby providing a reliable tool for routine risk assessment.

To investigate the residual status of dithiocarbamate (DTCs) pesticides in market available vegetables in Hulunbuir in 2024.

In 2024, a total of 144 vegetable samples from 6 kinds of categories, including leafy, root vegetables, fresh legumes were collected from commercial retail chain in Hulunbuir City. The content of DTCs pesticide residues (calculated as CS₂) were determined using solvent absorption gas chromatography-mass spectrometry (GC-MS). Statistical analysis was performed using Excel 2016 and SPSS 20.0 software.

The overall detection rate of DTCs pesticides was 59.03% (85/144), with residue levels ranging from 0.01 to 2.50 mg/kg (calculated as CS₂). Among the vegetable categories, both cabbage vegetables and bulb vegetables exhibited detection rates exceeding 80%, while leafy vegetables showed the highest residue level (2.50 mg/kg). The detection rates in Arong Banner and the main agricultural production areas were significantly higher than in other regions (χ²=33.329, P<0.05; χ²=12.491, P<0.05). In contrast, no statistically significant differences in detection rates were observed between samples from supermarkets and farmers’ markets, or between locally produced and non-local samples.

The detection of DTCs pesticide in commercially available vegetables in Hulunbuir is relatively common. It is recommended to promote scientific pesticide application techniques tailored to regional characteristics, strengthen pesticide residue monitoring, and further refine standard revisions. This study provides a scientific basis for risk assessment.

To investigate the influencing factors and optimization strategies for the matrix effects in pesticide residue analysis in Myrica rubra.

Pesticide residues in Myrica rubra were detected using liquid chromatography-tandem mass spectrometry under different conditions: Various sample pretreatment methods, different pesticide and matrix concentrations (low, medium, high), the addition of analyte protectants and varying liquid chromatography flow rates. The impact of these conditions on the matrix effect was analyzed. Analysis of variance (ANOVA) was used to compare the differences in matrix effects under different detection conditions, with a significance level of α=0.05.

Optimizing the pretreatment conditions based on the national standard method—specifically by adding graphitized carbon black adsorbent, replacing the salting-out agent and using acidified acetonitrile—effectively reduced or eliminated the matrix effects. The matrix effects varied with pesticide concentration, showed a weaker effect at medium concentrations (50 μg/L, 100 μg/L) compared to low (5 μg/L, 10 μg/L) and high concentrations (150 μg/L, 200 μg/L). Different matrix dilution factors also resulted in varying matrix effects: High dilution (×100) showed no matrix effect, medium dilutions (×50, ×10, ×5, ×2) exhibited a weak matrix effects, and the undiluted sample extract showed a strong matrix effects. The addition of analyte protectants significantly eliminated the matrix effects compared to the standard method. The matrix effects also differed with liquid chromatography flow rates, with a flow rate of 0.1 mL/min demonstrating a stronger matrix effect compared to 0.3 mL/min and 0.2 mL/min.

When detecting pesticide residues in complex matrices like Myrica rubra using liquid chromatography-tandem mass spectrometry, the matrix effect can be effectively reduced or eliminated by optimizing the sample pretreatment method, selecting appropriate matrix dilution factors and pesticide concentrations, adding analyte protectants and setting compatible flow rates.

To investigate the intervention effect of different fermentation groups on the model of alcoholic fatty liver disease (AFLD) by optimising the proportion of turpentine Pinus massoniana pollen compound and fermentation strains (morel mushroom and yeast), and to screen the optimal liver protection formula.

The mouse AFLD model was constructed by alcohol liquid feed, and a blank control group, model group, Pinus massoniana pollen+peach kernel unfermented group, Pinus massoniana pollen+peach kernel morel fermented group, Pinus massoniana pollen+peach kernel morel fermented group, Pinus massoniana pollen+peach kernel morel fermented group, Pinus massoniana pollen+peach kernel morel fermented group, Pinus massoniana pollen+peach kernel morel fermented group, Pinus massoniana pollen+peach kernel morel fermented group, yeast fermented group of kudzu root were set up. At the end of the intervention, serum samples were collected to test the levels of triglyceride (TG), total cholesterol (TC), alanine aminotransferase (ALT), aspartate aminotransferase (AST), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C); liver tissues were collected to determine the levels of hepatic TG, TC, malondialdehyde (MDA) and glutathione (GSH) levels, and liver pathology was analyzed by hematoxylin staining.

After the intervention of different fermentation groups, all of them showed a certain degree of hepatoprotective effect, and the effect was better than that of the unfermented group. Among them, the Pinus massoniana pollen+peach kernel+kudzu root Saccharomyces fermentation group had the most significant effect, followed by the Pinus massoniana pollen+peach kernel morel mushroom fermentation group. The serum TG, TC, ALT, AST and LDL-C levels in the yeast-fermented Pinus massoniana pollen+peach kernel+Pueraria lobata group were (0.62±0.04) mmol/L, (3.13±0.28) mmol/L, (0.68±0.15) U/mL, (2.66±0.31) U/mL and 0.75±0.08 mmol/L, respectively, which were reduced compared with those in the model group, respectively by 32.61%, 31.51%, 71.43%, 20.60% and 54.27%, respectively; and the serum HDL-C content was (2.17±0.32) mmol/L, which was increased by 33.13% compared with the model group. Its liver TG, TC and MDA contents were (0.09±0.02), (0.020±0.002) and(0.34±0.03) mmol/gprot, respectively, which were 55.00%, 45.95% and 37.04% lower compared with that of the model group; its liver GSH content was (9.52±3.25) μmol/gprot, which was 2.15 times higher than that of the model group.

Microbial fermentation can significantly enhance the hepatoprotective efficacy of Pinus massoniana pollen compound combination. Among them, yeast-fermented Pinus massoniana pollen+peach kernel+Pueraria lobata is the optimal solution, followed by yeast-fermented Pinus massoniana pollen+peach kernel, and this study provides experimental basis for the development of functional liver protection products.

To develop a Orah lactic acid bacteria fermented beverage with both excellent taste and health-promoting functions, and to conduct a comprehensive quality analysis thereof.

Single-factor experiments were conducted to investigate the effects of material-liquid ratio, white sugar addition amount, strain compound ratio, inoculation amount, fermentation time and temperature on the fermentation process. Basic parameters were screened by combining fuzzy comprehensive evaluation, and response surface methodology was further used for optimization and to establish a sensory evaluation prediction model.

The optimized optimal process parameters were determined as follows: Inoculation amount of 3%, fermentation temperature of 35 °C and fermentation time of 6 h, under these conditions, the fuzzy comprehensive evaluation value reached 0.9397. The physicochemical indexes of the fermented beverage were: Total acid content of 1.12 g/100 mL, total sugar content of 10.6 g/100 mL, pH 3.54 and soluble solid content of 12.4°Brix.

This study develope Orah lactic acid bacteria fermented beverage complies with GB/T 31121—2014 Fruit and vegetable juices and beverages. The research provide a theoretical basis for the development of high-value-added products from deep processing of Orah.

To develop a navel Citrus sinensis peel tea with suitable taste and unique flavor by inoculating the peels of Gan Nan navel Citrus sinensis with the Eurotium cristatum and conducting solid-state fermentation.

The single-factor experiment and response surface analysis method were adopted to optimize the fermentation process parameters of Gannan navel Citrus sinensis peel tea, and the sensory quality of the obtained product was comprehensively evaluated. Meanwhile, the in vitro antioxidant activity was evaluated by measuring the scavenging effects on 1, 1-diphenyl-2-picrylhydrazyl (DPPH) and 2, 2’-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) positive ion free radicals.

The optimal fermentation process parameters of Gannan navel Citrus sinensis peel tea were determined as follows: Inoculation Eurotium cristatum amount of 2.7%, fermentation temperature of 27 ℃, and fermentation time of 7 days. Under these conditions, the sensory score of the Gannan navel Citrus sinensis peel tea reached 91.29. The in vitro antioxidant results showed that the in vitro antioxidant results showed that, with vitamin C (VC) as the reference, the fermented Gannan navel Citrus sinensis peels inoculated with Trichosporon cutaneum and the unfermented Gannan navel Citrus sinensis peels both before and after fermentation had the ability to scavenge free radicals DPPH and ABTS⁺. When the concentration was lower than 5 mg/mL, the scavenging ability of the fermented Gannan navel Citrus sinensis peels inoculated with Trichosporon cutaneum and the unfermented Gannan navel Citrus sinensis peels on DPPH and ABTS⁺ free radicals was lower than that of VC; when the concentration was 5 mg/mL, the scavenging ability of the fermented Gannan navel Citrus sinensis peels inoculated with Trichosporon cutaneum and the unfermented Gannan navel Citrus sinensis peels on DPPH and ABTS⁺free radicals was comparable to that of VC; the half scavenging rates of these three for DPPH free radicals before and after fermentation were (2.1892±0.0583), (0.7345±0.0052), (0.0024±0.0002) mg/mL, respectively, and for ABTS⁺ free radicals were (2.2372±0.0672), (0.7461±0.0048), (0.0026±0.0002) mg/mL, respectively. The numerical differences were significant, indicating that the Gannan navel Citrus sinensis peels after Trichosporon cutaneum fermentation have stronger antioxidant activity, but their antioxidant activity is still lower than that of VC.

This study successfully develop a navel Citrus sinensis peel fermented tea with excellent quality, good taste and strong antioxidant function. The process formula is stable and feasible, which can provide theoretical and methodological technical support for the market industrialization promotion of navel Citrus sinensis peels.

To detect the heavy metal and metalloid content in aquatic products from 3 coastal areas of China, analyze the differences and correlations of heavy metal and metalloid levels among different types of aquatic products, assess the pollution level and health risks.

The content of 14 kinds of heavy metals and metalloid was determined using inductively coupled plasma mass spectrometry (ICP-MS). Their distribution and correlations in different aquatic products were analyzed, including the content differences between freshwater fish and marine fish, as well as pairwise comparisons among 3 sample categories: Fish, crustaceans and other aquatic products. Furthermore, the single-factor pollution index method, comprehensive pollution index method and target hazard quotient (THQ) method were employed to evaluate the heavy metal and metalloid pollution levels and health risks.

Among the 101 aquatic product samples, cadmium had the highest exceedance rate at 3.96%, while lead and chromium did not exceed standard limits. Statistically significant differences (P<0.05) were observed in the content of iron, cobalt, zinc, arsenic, selenium, strontium and cadmium between freshwater and marine fish. The content of chromium, iron, cobalt, nickel and lead were higher in other aquatic products than in fish and crustaceans.Significant differences (P<0.05) were found in the content of vanadium, manganese, copper and cadmium among the 3 categories. Pollution evaluation indicated that chromium, arsenic, cadmium and lead were at safe levels, while health risk assessment revealed higher health risks for chromium, lead, nickel and copper. Correlation analysis showed strong positive correlations between barium and manganese (r>0.9, P<0.05), barium and iron (r>0.8, P<0.05), barium and lead (r>0.8, P<0.05), as well as between iron and manganese and lead (r>0.8, P<0.05).

The overall heavy metal and metalloid pollution in aquatic products is relatively mild, but cadmium pollution is notable. Consumption of aquatic products poses certain health risks, necessitating strengthened regulation and control measures. Furthermore, the accumulation of heavy metals and metalloid is influenced not only by the type of aquatic product but also closely related to the presence of other heavy metal and metalloid components.

To investigate the contamination and antimicrobial resistance status of Salmonella and diarrheagenic Escherichia coli in commercially available foods in Jiangsu Province.

A total of 8110 samples of commercially available foods were collected in Jiangsu Province from 2022 to 2024. Salmonella and diarrheagenic Escherichia coli were detected and typed using the methods specified in the National work manual for food contaminant and hazardous factor risk monitoring, and antimicrobial susceptibility testing was performed by the broth microdilution method.

The overall detection rate of Salmonella and diarrheagenic Escherichia coli was 4.6% and 2.9%, respectively. Meat and meat products had the highest detection rates of both pathogens, which were 9.9% for Salmonella and 4.7% for diarrheagenic Escherichia coli, followed by aquatic products, with the rate of 2.4% and 1.9%. The 49 kinds of serotypes were identified among the 262 Salmonella strains, 37 strains could not be typed. Salmonella enteritidis, Salmonella typhimurium and Salmonella kentucky were the dominant serotypes. Among the 116 diarrheagenic Escherichia coli isolates, most were enteroaggregative Escherichia coli (EAEC), accounting for 87.1%. Both Salmonella and diarrheagenic Escherichia coli showed high resistance rates to tetracycline, ampicillin and chloramphenicol, while they were relatively sensitive to tigecycline and carbapenem antibiotics. The multi-drug resistance rates of Salmonella and diarrheagenic Escherichia coli were 65.3% and 59.5%, respectively.

Salmonella isolated from commercially available foods in Jiangsu Province have diverse serotypes.Both Salmonella and diarrheagenic Escherichia coli exhibit high levels of antimicrobial, multidrug resistance and complex resistance spectra. This issue demands great attention from animal husbandry and regulatory authorities.

To analyze the pollution characteristics of titanium dioxide (TiO₂) in commercially available edible mushrooms in Shenzhen from 2019 to 2023 and assess the human intake health risks.

From 2019 to 2023, the study collected 228 samples of commercially available edible fungi from Shenzhen, including Agaricus bisporus, Pleurotus eryngii and Flammulina velutipes. The content level of TiO₂ in the samples was determined by inductively coupled plasma optical emission spectrometry (ICP-OES), while the content level and particle size of titanium dioxide nanoparticles (TiO₂NPs) were analyzed using single particle inductively coupled plasma mass spectrometry (SP-ICP-MS). Based on these analyses, the pollution characteristics were explored, and the target hazard quotients (THQ) were used to assess the human health risks caused by TiO₂ exposure from commercially available edible fungi.

The content of TiO₂ in different types of edible mushrooms varied significantly. The mean TiO₂ content in Agaricus bisporus was 47.23 mg/kg with a detection rate of 83.33%, which was higher than that in Pleurotus eryngii (0.37 mg/kg, 23.33%) and Flammulina velutipes (0.32 mg/kg, 10.00%). The TiO₂ content in Agaricus bisporus fluctuated significantly interannually, with the average value reaching a peak of 59.86 mg/kg in 2021. Additionally, the average size of TiO₂NPs in Agaricus bisporus was greater than 100 nm, and there was a significant positive correlation between the concentration and size of nanoparticles. Health risk assessment showed that THQ for both adults and children were less than 1, with the risk for children approximately 1.8–1.9 times that for adults. Agaricus bisporus contributed prominently to the risk.

The health risk of TiO₂ exposure from commercially available edible mushrooms in Shenzhen is at a low level. However, it is necessary to pay close attention to the potential impacts of TiO₂ content fluctuations on the health risks of consumers, especially the children group.

To analyse of foodborne pathogen contamination in edible fungi sold in Chongqing from 2022 to 2024.

A total of 700 samples of wood ear and tremella were collected in 2022—2024 and tested for Listeria monocytogenes, Salmonella and Burkholderia gladioli according to the requirements of the national food safety standards.

A total of 112 positive samples were detected among 700 samples, with a detection rate of 16.00%. The detection rates of Listeria monocytogenes, Burkholderia gladioli and Salmonella were 7.14% (50/700), 6.86% (48/700) and 3.14% (22/700), respectively. The detection rates of pathogenic bacteria in rehydrated and fresh edible fungi were 20.00% (19/95) and 18.69% (94/503), respectively, which were significantly higher than that in dried edible fungi (6.86%, 7/102). The detection rate of foodborne pathogens in bulk edible fungi (including self-made simple packaging) was 18.41% (118/641), which was higher than that in pre-packaged products (3.39%, 2/59). Among the different sampling locations, the detection rate of farmers’ market was the highest at 22.84%(82/359), and the lowest at 2.27% (1/44) in online shops.

The edible fungi sold in Chongqing are more seriously contaminated by Listeria monocytogenes and Burkholderia gladioli, with rehydrated and fresh edible fungi posing a particularly higher risk of foodborne diseases. The degree of pathogenic contamination of edible fungi is related to the type of packaging and the distribution link. In this regard, it is recommended to strengthen the supervision of the whole chain of production, circulation and sales, form a closed-loop disposal of the whole process of traceability, and carry out science popularization activities through multiple channels to enhance the public risk awareness and protect consumer health.

To investigate the contamination levels of 3-monochloropropanediol esters (3-MCPDE)and glycidyl esters (GE) in grilled and fried meat, and assess their chronic dietary exposure risks.

The 20 electric grilled meat samples, 20 charcoal grilled meat samples and 20 fried meat samples were collected from 5 regions in Sichuan Province. The content of 3-MCPDE and GE was determined by ¹³C₃ isotope dilution-gas chromatography-tandem mass spectrometry. The chronic daily intake (CDI) was calculated by point estimation method based on the daily meat consumption data of Chinese adult residents. The chronic dietary exposure risks of 3-MCPDE and GE were separately evaluated by hazard quotient (HQ) and margin of exposure (MOE) based on the median contents (P₅₀) of the contaminants.

Among the 60 samples, the detection rates of 3-MCPDE and GE were 73.3% and 75.0%, with P₅₀ content levels of 29.3 μg/kg and 60.4 μg/kg, respectively. Among charcoal grilled meat samples, fried meat samples and electric grilled meat samples, the detection rates of 3-MCPDE were 85.0%, 95.0% and 40.0%, with P₅₀ content levels of 93.3 μg/kg, 31.6 μg/kg and not detected (ND), respectively; the detection rates of GE were 90.0%, 85.0% and 50.0%, with P₅₀ content levels of 1236.2, 25.3 and 6.9 μg/kg, respectively. For adult residents, calculated based on a consumption frequency of once per day for charcoal grilled meat, fried meat and electric grilled meat, the P₅₀ CDI of 3-MCPDE intake were 0.155, 0.053 and 0 μg·kg–1·d–1, with HQ values of 0.078, 0.026 and 0 (all less than 1), respectively; the P₅₀ CDI of GE intake were 2.060, 0.101 and 0.011 μg·kg^–1·d^–1, with MOE values of 1165, 23762 and 210111, respectively, indicating charcoal grilled meat posed a certain risk of chronic dietary exposure to GE. Further assessment of the dietary exposure risk of GE in charcoal grilled meat samples showed that, calculated based on a consumption frequency of 3 times per week, once per week and twice every two weeks, the P₅₀ MOE values were 2718, 8155 and 16310, respectively; charcoal grilled lamb contributed to 45% of the total exposure of GE in charcoal grilled meat.

Grilled and fried meat is commonly contaminated with 3-MCPDE and GE, with GE levels significantly higher than 3-MCPDE levels(P<0.05); the levels of 3-MCPDE and GE in charcoal grilled meat are significantly higher than those in fried meat and electric grilled meat (P<0.05); the chronic dietary exposure risk of 3-MCPDE ingested through grilled and fried meat, and the chronic dietary exposure risk of GE ingested through electric grilled meat and fried meat are acceptable, but the chronic dietary exposure risk of GE ingested through charcoal grilled meat requires attention. Reasonable control of consumption frequency and diversified selection of food types can reduce the risk of chronic dietary exposure.

To evaluate dissipation dynamics and dietary exposure risk of beta-cypermethrin and azoxystrobin in Vigna unguiculata (L.) Walp.

Based on standardized field residue trials, a quantitative analysis method for beta-cypermethrin and azoxystrobin in Vigna unguiculata (L.) Walp was established, which adopted acetonitrile extraction, purification by solid-phase extraction columns or the QuEChERS method, followed by detection using gas chromatography and liquid chromatography-tandem mass spectrometry. Through this method, the dynamic changes of residues of these 2 pesticides in Vigna unguiculata (L.) Walp were obtained, and the chronic dietary intake risk was evaluated.

The mass concentration of beta-cypermethrin and azoxystrobin had a good linear relationship with the peak area in the range of 0.005–1.000 mg/L, respectively. The average recoveries at 3 different spiked levels were 86.3%–104.1%, the relative standard deviations were 0.60%–2.31%, and the limits of quantitation were 0.01 mg/kg. The residual dissipation dynamics of beta-cypermethrin and azoxystrobin in Vigna unguiculata (L.) Walp conformed to the first-order kinetic equation, and the half-lives of dissipation were 2.8 d and 2.9 d, respectively.

The risk of chronic dietary intake of the 2 kinds of pesticides for people of different genders and age groups is far less than 100%, and there is no potential risk.

To establish a method for the simultaneous determination of 38 kinds of organic ultraviolet absorbents (OUVAs) in pork by ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).

The target compounds were extracted with acetonitrile and purified by pass-through solid-phase extraction EMR-Lipid, followed by gradient elution with 2 kinds of mobile phase systems:Methanol-0.1% formic acid aqueous solution and methanol-0.1% ammonia aqueous solution. The separation was performed on an Acquity UPLC BEH C₁₈ column (100 mm×2.1 mm, 1.7 μm). Mass spectrometry analysis was conducted using positive and negative electrospray ionization sources in multiple reaction monitoring mode, with targeted quantification performed by the internal standard method.

Within their respective mass concentration range, 38 kinds of OUVAs showed good linear relationships (r²≥0.9958), with the limits of detection ranging from 0.002 to 0.300 μg/kg and the limits of quantitation from 0.005 to 0.900 μg/kg. At 3 fortification levels in blank matrices, recoveries ranged from 61.2% to 128.2%, with relative standard deviations all below 11.8%. This method was applied to 19 commercially available pork samples, identifying 17 kinds of OUVAs. The concentration levels of ΣOUVAs ranged from 4.28 to 30.39 μg/kg.

This method is portable, efficient, reproducible and capable of multiple target compounds, making it suitable for the trace determination of 38 kinds of OUVAs in pork.

To analyze, identify and quantitatively determine active components and nutrients in Meizhou Shatian pomelo flowers.

Ultra performance liquid chromatography-quadrupole/exactive-orbitrap high resolution mass spectrometry (UPLC-QE-Orbitrap-HRMS) combined with workstation TraceFinder 5.0 and its Chinese medicine database were used to analyze non-volatile components of Shatian pomelo flower. Active compounds and nutrients in pomelo flowers were determined by other various detection techniques.

A total of 51 kinds of non-volatile active components were identified in pomelo flowers, including 19 kinds of flavonoids, 11 kinds of coumarins, 8 kinds of terpenoids, 3 kinds of organic acids, 2 kinds of aldehydes, 2 kinds of amino acids, 2 kinds of nucleosides, 1 kind of phenol, 1 kind of alkaloid and 2 kinds of other compounds. Types and content of flavonoids in pomelo flowers were rich. Naringin, total saponins, fat, protein, dietary fiber, carbohydrate, 5 kinds of vitamins and 10 kinds of nutrient elements in dried pomelo flowers were determined quantitatively in this study. The content of naringin was high to 13.9 g/100 g. The content of saponins, vitamin C and vitamin E were relatively high.It also contained a variety of trace elements needed by human body.

Pomelo flowers are rich in active components and nutrients. This study provides a scientific basis for pomelo flowers related to the formulation of quality standards, the comprehensive utilization of resources and product development.

To establish a method to detect fluoride content based on the fluoride riboswitch transcription system and clustered regularly interspaced short palindromic repeats-associated protein 12a(CRISPR/Cas12a).

The system utilized fluoride riboswitch to regulate transcription of full-length or truncated RNA in the presence/absence of fluoride, which was then detected by CRISPR/Cas12a-mediated fluorescence signal. Selectivity and interference analyses were conducted to optimize CRISPR/Cas12a detection system, and the method was applied to measure fluoride content in Euphausia superba.

This study successfully established a fluorescence detection method based on a fluoride riboswitch transcription reaction system and CRISPR/Cas12a, which completed sample detection within 1.5 h with the results consistent with those obtained by the national standard fluoride ion-selective electrode method.

The fluoride detection method established in this study for Euphausia superba based on a fluoride riboswitch transcription reaction system and CRISPR/Cas12a, demonstrates high specificity and accuracy, showing potential for fluoride content analysis.

To establish an analytical method based on the fusion fingerprint technology of elements and organic components, achieve precise origin tracing of Myrica rubra ‘Dongkui’ from major production areas such as Zhejiang, Fujian and Yunnan in China.

Myrica rubra ‘Dongkui’ samples were collected from 5 representative regions in Zhejiang (Taizhou, Jinhua, Wenzhou), Fujian and Yunnan. Inductively coupled plasma mass spectrometry (ICP-MS), spectrophotometry, acid–base titration and ion chromatography were employed to determine mineral elements and organic components, including total anthocyanins, titratable acidity, sugar-to-acid ratio, and solid-to-acid ratio. Chemometric methods such as principal component analysis (PCA), Fisher discriminant analysis, and analysis of variance were applied to construct a discriminant model for origin identification.

There were significant differences in the content of 12 kinds of elements including Al, Ti, Fe, Ni, Cu, Zn, Ga, Sr, Cd, Sn, Sb and Pb among different production areas of Myrica rubra. Among them, the content of Al, Ti, Fe, Cu, Zn, Ga, Cd and Sn in the Yunnan production area were the highest, while the content of Ni, Cd and Pb in the Fujian production area were the lowest. In terms of organic components, total anthocyanins, titratable acid, sugar-acid ratio and solid-acid ratio also showed significant differences among production areas (P<0.05). Based on the discriminant model established using fused data, the sample points from the three origins were clearly distinguished in the PCA plot, with no overlap between Yunnan and Fujian/Zhejiang, and only occasional overlap between Fujian and Zhejiang. The initial discriminant accuracy reached 97.3%, and the cross-validation discriminant rate was 94.7%, which was significantly superior to single-component analysis methods.

The integration of fingerprint technology for elemental and organic components combined with chemometric analysis can effectively achieve the accurate discrimination of the origin of Myrica rubra ‘Dongkui’, providing a reliable multi-technique combined strategy for the origin traceability and geographical indication protection of agricultural products.

To clarify the effects of deastringency and 1-methylcyclopropene (1-MCP) treatments on the electrical properties of Diospyros kaki L. Huoshi during storage.

High-concentration short-term CO₂ treatment was applied to Diospyros kaki L. Huoshi for deastringency, and 500 nL/L 1-MCP was used for preservation, respectively, with untreated fruits as the control (CK). Inductance-capacitance-resistance (LCR) impedance analyzer was employed to determine the dynamic changes of impedance, inductance, capacitance and conductance of the treated fruits at 5 frequencies (0.1, 1.0, 10.0, 100.0 and 1000.0 kHz) during room-temperature storage.

The impedance and inductance of Diospyros kaki L. Huoshi showed a power function decrease with increasing frequency, while conductance increased in a power function pattern, and capacitance exhibited a slow decrease followed by fast increase manner. During storage, the impedance and inductance of fruits in all treatments decreased in a linear relationship, and capacitance and conductance increased in an exponential relationship. The frequency of 1.0 kHz was the sensitive frequency for changes in fruit impedance, inductance and capacitance. The 1-MCP treatment significantly inhibited the decrease rate of impedance and inductance, as well as the increase rate of capacitance and conductance. At 1.0 kHz, after 24 d of storage, the impedance and inductance of 1-MCP treated fruits were 60.8% and 59.7% higher than those of the CK, respectively; while the capacitance and conductance were 60.6% and 44.6% of those in CK, respectively. Deastringency accelerated the changing process of electrical parameters: On the 6th day, the impedance and inductance decreased by 88.9% and 88.8% compared with 0 d, respectively; the capacitance and conductance were 9.2 and 15.4 times those on 0 d, respectively.

Deastringency and 1-MCP treatments only alter the time and amplitude of electrical parameter variations in Diospyros kaki L. Huoshi persimmon, but not the pattern;the electrical parameters are sensitive to above 2 kinds of treatments. This study provides a reference for the non-destructive detection of deastringency efficiency and storability and 1-MCP preservation effect of persimmon fruits.

To establish a method for determination of 9 kinds of biogenic amines in aquatic products by tandem ion chromatography-ultraviolet detection (IC-UV).

Fish samples were ultrasonically extracted with 0.2 mmol/L methanesulfonic acid solution then protein was precipitated with acetonitrile, and analyzed after filtration through a membrane. The 9 kinds of biogenic amines and coexisting ions in the samples were separated on an IonPac CS17 cation exchange chromatographic column (250 mm×4 mm, 7 µm). The experimental conditions, including eluent condition, column temperature and detector wavelength range, were optimized to achieve optimal performance.

The 9 kinds of biogenic amines exhibited wide linear ranges: Octopamine, tyramine and tryptamine showed good linearity in the mass concentration range of 0.2–20.0 mg/L, putrescine, cadaverine, spermidine and spermine in the mass concentration range of 0.02–20.00 mg/L; and histamine and phenethylamine in the mass concentration range of 0.10–20.00 mg/L; with linear correlation coefficients (r²)≥0.9960 and satisfactory recoveries (83.8%–122.9%). The limits of detection for putrescine, cadaverine, histamine, phenethylamine, spermidine, spermine, octopamine, tyramine and tryptamine were 0.23, 0.30, 1.63, 1.56, 0.21, 0.26, 1.97, 2.50 and 2.88 mg/kg, respectively.

This method is simple, eliminates the complex derivatization pretreatment, and offers excellent selectivity and high sensitivity, making it suitable for the detection and analysis 9 kinds of biogenic amines in aquatic products.

To establish a method for the simultaneous detection of benzoic acid, sorbic acid and dehydroacetic acid in pre-made meals by high performance liquid chromatography.

Sodium hydroxide solution was added to the sample for ultrasonic extraction. Protein was precipitated with potassium ferrocyanide and zinc acetate solution. Separation was carried out using an Agilent XDB-C₁₈ (4.6 mm×250 mm, 5 μm)chromatographic column. The mobile phase was ammonium acetate solution and methanol (93:7, V:V), with a flow rate of 1 mL/min and a column temperature of 30 ℃. The detection was carried out by a diode array detector with detection wavelengths of 230 nm and 293 nm. At the same time, the spectra of the standard solution and the sample solution were collected respectively by a diode array detector. By comparing the spectra of the target peak in the standard and sample solutions, the samples were further qualitatively confirmed.

The 3 kinds of preservatives had a good linear relationship within the range of 0.5–100.0 mg/L, with correlation coefficients (r)greater than or equal to 0.9994. The limits of detection were 1.7 mg/kg, the limits of quantitation were 5.0 mg/kg, the recovery rates were 92.0%–104.0%, and the relative standard deviations were 0.1–1.6%.

This method is simple, rapid, has good reproducibility and high recovery rate, and is suitable for the rapid detection of 3 kinds of preservatives, namely benzoic acid, sorbic acid and dehydroacetic acid in pre-made meals.

To establish a method for the determination of dilauryl thiodipropionate (DLTP) in foods by gas chromatography-tandem mass spectrometry (GC-MS/MS).

Samples were extracted with acetonitrile. For lipid-rich samples, a solvent system composed of hexane-saturated acetonitrile was employed for defatting and purification. The resulting extract was then subjected to centrifugation, dehydration and filtration through a microporous membrane to complete sample preparation. The established GC-MS/MS method, combined with an external standard calibration approach, was applied to determine DLTP in various food matrices, including fruits, vegetables, puffed foods, fried nuts and seeds and fried flour-based products.

DLTP exhibited good linearity in the mass concentration range of 0.1–2.0 mg/L, with correlation coefficients all greater than or equal to 0.996. At different matrixes and different spiked concentration levels, the method demonstrated recoveries ranging from 81.8% to 107.8%, with relative standard deviations of 0.59%–5.75% (n=6). The limit of detection was 0.3 mg/kg, and the limit of quantitation was 1.0 mg/kg.

The developed method is simple to perform, accurate and exhibits satisfactory sensitivity. It is suitable for the quantitative determination of DLTP in foods and can provide reliable technical support for the safe use and regulatory oversight of this food additive.

To evaluate the hypoglycemic effect of novel composite soluble dietary fiber (NCSDF) on db/db mice, and explore whether it exerts its hypoglycemic action through the gut microbiota-short-chain fatty acids(SCFAs)-glucagon-like peptide-1 (GLP-1) signaling axis.

The 8 weeks-old male db/db mice were divided into a model group, low-, medium- and high-dose NCSDF treatment groups, and a control group of db/m mice, with 10 mice in each group. After continuous administration for 8 weeks, fasting blood glucose, insulin and GLP-1 levels were measured in each group. The gut microbiota structure and metabolite levels were analyzed using 16S rRNA sequencing and SCFAs detection.

NCSDF intervention reduced fasting blood glucose levels, improved insulin resistance, and upregulated serum GLP-1 levels in db/db mice. Additionally, NCSDF intervention modulated the gut microbiota structure, increasing the abundance of SCFA-producing bacterial genera such as Bacteroides, Lachnospiraceae and Prevotellaceae, and elevated the concentrations of acetic acid, propionic acid, butyric acid, isobutyric acid and valeric acid in the intestinal content.

NCSDF may promote GLP-1 release and enhance insulin sensitivity in peripheral tissues by modulating the gut microbiota-SCFAs-GLP-1 signaling axis, thereby exerting its hypoglycemic effect.

To establish a method for quantitative determination of 2 kinds of novel tadalafil derivatives in blended wine, coffee and table candy by ultra performance liquid chromatography-tandem mass spectrometry.

Waters HSS T₃ (2.1 mm×100 mm, 1.8 μm) reversed-phase chromatographic column was used for gradient elution with 0.1% formic acid water and acetonitrile as the mobile phase, and was detected by mass spectrometry with multiple reaction monitoring.

In the mass concentration range of 1.0–20.0 ng/mL, there was a good nonlinear relationship between 2 kinds of new tadalafil derivatives, diethylaminopretadalafil and dipropylaminopretadalafil (r²>0.99); the limits of detection of the method were all 0.05 mg/kg and the limits of quantitation were all 0.10 mg/kg. The average recovery rate range at the 3 levels of 1, 2 and 10 times limits of quantitation were 82.5% to 95.6%, and the relative standard deviation were 1.9%–7.8% (n=6). The method had good accuracy.

This method is simple, accurate and sensitive, and can be used for the accurate and rapid determination of the content of diethylaminopretadalafil and dipropylaminopretadalafil in blended wine, coffee and table candy.