To establish an extraction process of proteins in Trichiurus lepturus processing by-products by ultrasonic pretreatment-enzyme method and investigate the fundamental properties of the proteins.

Taking Trichiurus lepturus processing by-products as raw materials, the enzymatic extraction conditions of protein by trypsin were optimized through single-factor experiments and orthogonal tests. On this basis, 4 kinds of pretreatment methods including acid pretreatment, alkali pretreatment, thermal pretreatment and ultrasonic pretreatment were applied to Trichiurus lepturus processing by-products, and the process parameters of ultrasonic pretreatment were further optimized via single-factor experiments and orthogonal tests.

Trypsin was the optimum protease, and the optimum enzymolysis conditions were as follows: Enzymolysis temperature 55 ℃,solid-liquid ratio 1:2 (g:mL), enzymolysis time 1.5 h, enzyme dosage 0.5%, the protein recovery of enzymatic hydrolysate was 76.05%±0.69%. The optimum technological conditions of ultrasonic pretreatment were as follows:Ultrasonic power 180 W, ultrasonic time 40 min, ultrasonic temperature 40 ℃. Proteins were extracted under optimal conditions of ultrasound pretreatment with a protein recovery rate of 85.93%±0.62%. The highest content among amino acids was glycine, followed by glutamate and alanine, and had strong 2,2’-azinobis-(3-ethylbenzthiazoline-6-sulphonate) diammonium salt (ABTS) cationic radical, 2,2-diphenyl-1-picrylhydrazyl(DPPH) radical scavenging activity, and Fe³⁺ reducing activity.

Ultrasonic pretreatment-enzyme method achieves efficient recovery of protein from Trichiurus lepturus processing by-products. The extracted proteins exhibit strong antioxidant capacity, providing technical support for the high-value utilization of Trichiurus lepturus processing by-products.

To optimize the processing technology of green jujube pulp and investigate its change s in active substances and antioxidant activity.

Shanxi Banzao was used as the raw material, with direct pulping as the traditional process reference, and the effects of direct pulping, microwave-assisted pulping, and ultrasonic-assisted pulping on the flavonoids and polyphenols content in the pulp were compared to determine the optimal pulping method. A single-factor and orthogonal experimental design was employed to optimize the ultrasonic-enzymatic hydrolysis composite process, and the content of active components and antioxidant activity in the pulp were measured. Subsequently, the active component content and antioxidant properties of 9 kinds of Shanxi green jujube pulps were compared before and after process optimization, and high-quality varieties were selected through standardized relative value heat map analysis.

Ultrasonic-assisted pulping significantly increased the polyphenol content in the pulp and was identified as the optimal method. The optimized ultrasonic-enzymatic hydrolysis parameters were determined as follows: Ultrasonic power 450 W, feed-to-pulp ratio 1:20 (m:V), and enzyme addition rate 0.7%. Under these conditions, the total flavonoid content in Banzao pulp reached 392.46±5.43 mg/100 g, while the half maximal inhibitory concentration values for 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS⁺) scavenging capacities were as low as 4.51 mg/mL and 15.9 mg/mL, respectively. The total vitamin C and dietary fiber contents increased by 25.2% and 0.8%, respectively.Heat map analysis identified 3 green jujube varieties-Banzao, Youzao and Tuntun-as those with the highest overall quality.

This study optimized and established the optimal production process for green jujub pulp, and the content of its active ingredients and antioxidant activity are effectively enhanced. The findings provide theoretical support for optimizing the processing techniques and selecting suitable varieties of green jujube pulps, which demonstrate significant practical value and potential for widespread application.

To establish a rapid model for varietal discrimination of Chinese red wines by leveraging the differences in antioxidant activity among different varieties.

The total phenolic content, total flavonoid content, cupric ion reducing antioxidant capacity, 1,1-diphenyl-2-picryl-hydrazyl radical scavenging capacity and 2,2’-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) ammonium salt radical cation scavenging capacity of different varieties of Chinese red wines (Pinot Noir, Merlot, Cabernet Gernischt and Cabernet Sauvignon) were determined and compared. Meanwhile, principal component analysis (PCA), orthogonal partial least squares-discriminant analysis (OPLS-DA) and support vector machine (SVM) algorithms were combined to establish a varietal identification model for Chinese red wines.

Comparative analysis revealed that the order of antioxidant activity of the 4 varieties was: Cabernet Sauvignon>Merlot>Cabernet Gernischt>Pinot Noir. On this basis, the constructed PCA (R²X_cum=0.819) and OPLS-DA (R²X_cum=0.952, R²Y_cum=0.424, Q²_cum=0.387) models effectively characterized the data features and intergroup differences. The SVM varietal identification model achieved a cross-validation accuracy of 94.40%, with 100.00% accuracy in the training set and 96.26% accuracy in the test set.

Based on the variety-specific antioxidant activity differences of Chinese red wines, combined with multivariate statistical methods and machine learning algorithms, rapid and accurate discrimination of Chinese red wine varieties can be effectively achieved.

To explore the effects of cooking time on the flavor and texture characteristics of 3 kinds of common cereal porridges, namely rice porridge, millet porridge and maize porridge, and to compare the differences in glycemic index (GI) among different grain porridges.

The flavor and texture characteristics of the porridges cooked in a rice cooker were determined by gas chromatography-mass spectrometry and texture analyzer. A human trial was conducted to measure the GI values of the porridges, and the high-GI porridge was further optimized.

Flavor analysis revealed that aldehydes and esters were the dominant volatile compounds in the cereal porridges. Specifically, rice porridge was characterized by the fresh note of nonanal and hexanal, millet porridge was rich in vanillin and undecanal, while maize porridge exhibited a fruity note mainly from esters such as methyl heptanoate. Texture analysis showed that hardness of all 3 kinds of porridges decreased with prolonged cooking time, with maize porridge showing the highest hardness and rice porridge the lowest. Sensory evaluation indicated that rice and millet porridges cooked for 30 min achieved the highest overall scores, whereas maize porridge reached its optimum at 50 min. GI tests demonstrated that rice porridge was a high-GI food, millet porridge was a medium-GI food, and maize porridge was a low-GI food. Using rice porridge as the base, the formula was optimized by adding milk powder. The resulting low-GI (41.1) rice milk porridge with 13% milk powder showed a 47.4% reduction in GI compared with plain rice porridge.

Reasonable control of cooking time can optimize the eating quality of cereal porridges, and the addition of dairy products can effectively reduce their GI. This study provides a simple dietary improvement strategy for consumers to select daily porridges and manage glycemic control.

To study the effects of the krill oil and oyster soft capsules on bone mineral density, bone metabolism and inflammatory state in ovariectomized rats.

The ovariectomized rat models were established and divided into sham operation group, ovariectomized control group, low, medium and high dose of krill oil and oyster soft capsule groups and calcium carbonate group, which were continuously administered for 3 months.The body weight data were recorded weekly. At the end of the experiment, the changes in body weight, femoral bone calcium content, bone mineral density of the middle and distal femur, and the expression levels of osteoprotegerin(OPG)-receptor activator of nuclear factor kappa-B (RANK)-RANK ligand (RANKL) signaling system related molecules in serum were measured.

The low, medium and high doses of krill oil and oyster soft capsules significantly increased femoral bone calcium content and bone mineral density of distal femur in ovariectomized rats;middle and high doses of krill oil and oyster soft capsules could significantly increase bone mineral density of middle femur, which was not lower than that of calcium carbonate treatment group. The results of bone metabolism markers showed that the expression levels of alkaline phosphatase, osteocalcin and procollagen type I amino acid propeptide significantly increased in the high dose group of kril oil and oyster soft capsules, while the expression levels of bone alkaline phosphatase and C-telopeptide of type I collagen were significantly inhibited in the low, medium and high dose groups. The results of OPG-RANKL-RANK signaling system related molecular detection showed that the low-dose kril oil and oyster soft capsules significantly inhibited the levels of osteoprotegerin, and the medium and high dose significantly inhibited the levels of osteoprotegerin, interleukin-6 and interleukin-8 in serum of ovariectomized rats, and significantly increased the level of transforming growth factor-β1.

The krill oil and oyster soft capsules can improve bone mineral density, bone metabolism and ameliorate inflammatory state in ovariectomized rats through multiple mechanisms such as providing calcium source, maintaining the balance between bone formation and bone resorption, anti-inflammation, regulating OPG-RANKL-RANK signaling system, and reducing high bone turnover rate.

To investigate the effects of glucose fermentation products with other raw materials on the quality of pickled vegetables during storage at 37 ℃.

The 3 kinds of food raw materials—glucose fermentation products, vinegar powder and soybean dietary fiber were selected. And the pickled radish was as the test object. The effects on the sensory quality and shelf life of pickled vegetables with three food materials used individually were investigated through single-factor experiment. The optimal physical mixing ratio had been determined through an L₉(3⁴) orthogonal array design.

When 3 kinds of materials were used alone, the sensory quality of pickled vegetables was improved effectively and aerobic plate count was suppressed. The combination of 3 kinds of materials was 1.5 g/kg of glucose fermentation products, 1.5 g/kg of vinegar powder and 4.0 g/kg of soybean dietary fiber. The pickled vegetables were stored for 24 days at 37 ℃ with satisfactory sensory quality, aerobic plate count no more than 5.88 lg(CFU/g), coliforms no more than 2.99 lg(CFU/g) and amino acid nitrogen no less than 0.12 g/kg. The shelf life achieved was the same as that reached by using sodium dehydroacetate and superior to that achieved by using potassium sorbate.

Various qualities of pickled vegetables are effectively enhanced during their shelf life with the use of glucose fermentation products, vinegar powder and soybean dietary fiber. The common chemical preservatives are replaced to inhibit the growth of spoilage microorganisms. The reliable solution is provided for the green upgrading of the pickled vegetable industry.

To investigate the optimal processing parameters for Ipomoea batatas-Morus alba flavored yogurt, analyze its quality, and develop a yogurt with a unique flavor and excellent quality.

First,the process conditions—including the ratio of Ipomoea batatas powder to Morus alba juice, sugar addition, and fermentation time—were optimized through single-factor and response surface experiments, using viscosity,water-holding capacity, whey separation rate, acidity and sensory evaluation as indicators Subsequently, under the optimized process conditions, the quality of the yogurt was analyzed based on indicators such as protein, fat, non-fat milk solids, acidity, lactic acid bacteria count and mold count.

The optimal process parameters for Ipomoea batatas-Morus alba yogurt were determined as follows: A Ipomoea batatas powder to Morus alba juice ratio (m:m) of 3:5, a sucrose addition of 6% and a fermentation time of 5.0 h. Under these conditions, the sensory score of the resulting yogurt was 87.04 points, which was very close to the theoretically predicted value of 87.32 points. Analysis of the quality indicators of this yogurt revealed the following: Protein content of 3.4 g/100 g, fat content of 2.7 g/100 g, non-fat milk solids of 9.1 g/100 g, acidity of 65.5°T, lactic acid bacteria count of 1.9×10⁸ CFU/g, mold count<1.0 CFU/g, and no pathogenic bacteria were detected. The quality meets all the requirements specified in GB 19302—2025 National food safety standard for fermented milk.

This study optimize a composite-flavored yogurt that combines the aromas of sweet potato and fruit, providing feasible process parameters and data support for the industrial production of multi-flavored fermented milk. It holds significant importance for the deep processing of specialty fruit and vegetable raw materials and the expansion of the industrial chain.

To study the element distribution characteristics in 4 kinds of poultry pre-made dishes,including chicken, duck, visceral and claw sold in Beijing in 2024, and evaluate the dietary exposure risk of harmful elements.

Inductively coupled plasma mass spectrometry was used to determine 14 kinds of elements in 46 poultry pre-made dishes sold in Beijing. Pollution index method, target hazard quotient/total target hazard quotient(THQ/TTHQ), hazard quotient (HQ), hazard index (HI) and carcinogenic risk index (CR) were used to evaluate the health risks of harmful elements.

All 14 kinds of elements were detected in poultry pre-made dishes, with median content of aluminum, manganese, boron, chromium, nickel and molybdenum exceeding 0.01 mg/kg. The detection rates of harmful elements were as follows: Arsenic (100%)>chromium (97.8%)>lead (41.3%) and mercury(41.3%)>cadmium (39.1%). The content of these elements were all below the standards of the GB 2762—2022 National food safety standard-Limits of pollutants in food. There were significant differences in the median values of 14 kinds of elements among 4 kinds of poultry pre-made dishes. Among the visceral pre-made dishes, the content of vanadium, manganese, cobalt, arsenic, molybdenum, cadmium and lead were the highest. Among the claw pre-made dishes, the content of mercury was the highest, followed by lead. Among the chicken pre-made dishes, the content of arsenic and lead were the lowest. The median chromium content in 4 kinds of poultry pre-made dishes showed little variation, but the average chromium content (0.10 mg/kg) in chicken pre-made dishes was approximately twice that of the other 3 kinds of poultry pre-made dishes, with Kung Pao chicken exhibiting a notably high chromium characteristic. The pollution index for lead, cadmium, arsenic, mercury and chromium were all less than 0.7,indicating that the sample was not contaminated with harmful elements. For the assessment of non-carcinogenic health risks, 2 sets of assessment methods from the United States Environmental Protection Agency and the World Health Organization/International Codex Alimentarius Commission were employed. The THQ/TTHQ and HQ/HI assessment values for cadmium, mercury and chromium were all less than 1, indicating that the risks were at an acceptable level. The results from both assessment methods were consistent, and both identify that Cd posed the highest risk in visceral pre-made dishes, while Hg posed the highest risk in claw pre-made dishes. The CR of Pb in 4 kinds of poultry pre-made dishes was less than 1×10^–6, indicating no carcinogenic risk. The CR of arsenic ranged from 1×10^–6–1×10^–4, indicating an acceptable carcinogenic risk.

The health risks posed by harmful elements in 4 kinds of poultry pre-made dishes sold in Beijing are at a safe level. Although the detection rate and content levels of multiple elements in claw pre-made dishes are relatively low, the mercury and lead contents in these dishes are at a higher level among the 4 kinds of poultry pre-made dishes, which should be recommended to strengthen monitoring.

To investigate the residual levels of quinolone antibiotics in aquaculture products from a city in East China and assess their health risks to residents via dietary intake.

From 2023 to 2025, a total of 768 aquaculture products were randomly collected from aquaculture farms of the city. The residues of 6 kinds of quinolone antibiotics, including enrofloxacin, ciprofloxacin and ofloxacin, etc, were determined by liquid chromatography-tandem mass spectrometry. A point assessment model was employed to estimate the daily exposure doses for different age groups, and the hazard quotient method was applied for dietary risks.

The 3 kinds of antibiotics were detected, including enrofloxacin, ciprofloxacin and ofloxacin, with an overall detection rate of 20.44% and an exceedance rate of 1.69%. Enrofloxacin showed the highest rate (19.01%), with residue concentrations ranging from 1.03 μg/kg to 1177.00 μg/kg. Dietary risk assessment indicated that under both average and maximum residue concentration exposure scenarios, the hazard quotients for all age groups were below 1.

The dietary health risks posed by quinolone antibiotic residues in aquaculture products from the city to various age groups are low. However, continuous efforts should be made to strengthen the supervision of drug use during aquaculture practices, so as to ensure that the dietary risks to residents remain at acceptable levels.

To establish a method for the rapid determination of 6 kinds of biogenic amines in fermented milk by pass-through solid-phase extraction coupled with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS).

After extraction with a 2% formic acid/acetonitrile solution, samples were purified using an Oasis PRiME HLB solid-phase extraction cartridge to efficiently remove interferences such as proteins and phospholipids. Chromatographic separation was performed on a hydrophilic interaction chromatography column. Mass spectrometric detection was carried out in multiple reaction monitoring mode, and quantification was achieved by the internal standard method.

The method was validated and demonstrated good linearity (r²≥0.996)for the 6 kinds of biogenic amines within a certain concentration range, the limits of detection were 0.20 µg/kg–1.80 µg/kg,the limits of quantitation were 0.67–6.00 µg/kg. Spiked recoveries were 76.0%–117.8%, with relative standard deviations below 13%. Analysis of commercial fermented dairy samples revealed that tyramine was the predominant biogenic amine, with concentrations ranging from 0.80 to 1.70 mg/kg, while safety-risk-associated biogenic amines such as histamine were detected at extremely low levels or were not detected.

The established method,by incorporating the Oasis PRiME HLB purification strategy, effectively resolves the critical issue of phospholipid interference in dairy products. It features advantages such as simple and rapid sample preparation, high sensitivity and strong anti-interference capability. The method is suitable for the high-throughput determination of multiple biogenic amines in fermented dairy products, providing robust technical support for the quality control and safety risk assessment of these products.

To establish an method for the determination of tamoxifen in solid drinks, liquid drinks,hard capsules, soft capsules and table candy by high performance liquid chromatography-tandem mass spectrometry.

The samples were extracted with 0.1% formic acid acetonitrile solution as ultrasonic extractant, and the analytical solution was purified by pass-through solid-phase extraction to detect tamoxifen in solid drinks, liquid drinks, hard capsules, soft capsules and tablet candy. Agilent Eclipse Plus RRHD C₁₈ column (100 mm×2.1 mm,1.8 μm) was used for separation, electrospray negative ion mode, tandem mass spectrometry for detection, and external standard method for quantification.

That concentration of tamoxien was good linear relationship within the range of 1.0–100.0 ng/mL, and the correlation coefficient was above 0.999; the limit of detection was 0.015 mg/kg; The limit of quantitation was 0.050 mg/kg.

The method has been verified by the method with high sensitivity, good stability and simple operation, which can meet the requirements of precision and sensitivity for the detection of tamoxifen in solid drinks, liquid drinks, hard capsules, soft capsules and tablet candy.

To establish a method for the determination of 12 kinds of antiviral drugs (ATVs) in shellfish and dried shellfish products by ultra performance liquid chromatography-tandem mass spectrometry.

Samples were extracted with acetonitrile containing 1% formic acid, purified using FaVEx-NM50 multi-veterinary drug residue clean-up columns, concentrated under nitrogen in a water bath, and reconstituted with a redissolving solution to obtain the test solution. The analytes were separated on a ZORBAX Eclipse Plus C₁₈ column using gradient elution with a mobile phase consisting of acetonitrile‑methanol (80:20, V:V, containing 0.1% formic acid) and 5 mmol/L ammonium acetate (containing 0.1% formic acid). Detection was carried out by ultra performance liquid chromatography-tandem mass spectrometry in multiple reaction monitoring mode, and quantification was performed using the internal standard method.

The 12 kinds of target compounds showed good linearity over certain concentration ranges, and the limits of detection and recoveries met the requirements. The correlation coefficients (r) of the calibration curves ranged from 0.9931 to 0.9997, limits of detection were 0.07–1.50 μg/kg, and limits of quantitation were 0.14–3.00 μg/kg. At 3 spiked levels (n=6), the average recoveries in mussel matrix ranged from 66.7% to 106.2% with relative standard deviations of 1.0%–11.6%,while in dried scallop matrix the average recoveries ranged from 69.1% to 109.5% with relative standard deviations of 0.9%–10.3%. Meanwhile, 161 batches of shellfish and dried shellfish products were purchased and analyzed for the target compounds using this method. The results showed that amantadine was detected in 37 batches. A dietary exposure risk assessment of amantadine residues was conducted by combining the residue data with dietary consumption and population data. The assessment indicated that the current amantadine residues in shellfish posed a low risk to human health.

The method is sensitive, accurate, simple and rapid in sample pretreatment,making it suitable for the determination of ATVs residues in shellfish.

To screen the differential metabolites of amino acids during the autolysis process of the Coprinellus micaceus by amino acid targeted metabolomics, and analyze the potential pathways of its autolysis process.

The samples of Coprinellus micaceus were collected, the samples were divided into a control group and an autolysis group, with 6 samples in each group, totaling 12 samples. The 24 kinds of amino acids in the samples were detected by ultra-performance liquid chromatography-tandem mass spectrometry. The sample repeatability and the trend of overall metabolic differences were evaluated through multivariate statistical principal component analysis (PCA). Orthogonal partial least squares discriminant analysis (OPLS-DA) maximizes differences between groups and screens for differential metabolites and the Kyoto encyclopedia of genes and genomes (KEGG)pathway enrichment analysis was conducted for the differential metabolites.

Through PCA and OPLS-DA,the contribution rate of principal component 1 (PC1) was 52.6%, and that of principal component 2 (PC2) was 24.1%.The autolysis group (R) and the control group (W) were completely separated, and the amino acid metabolites of Coprinellus micaceus disseminatus during autolysis showed significant differences. Differential metabolites were screened under the conditions of variable importance projection (VIP)≥1, P<0.05, and |log₂FC|≥0.58. The differential amino acids during the autolysis of Coprinellus micaceus were ornithine downregulated by 2.7-fold, and tryptophan, citrulline and cysteine upregulated by 1.8-fold, 2.5-fold and 1.9-fold, respectively. Cluster analysis results showed significant differences in amino acid metabolites between the autolysis group and the control group.Cysteine, tryptophan, and citrulline were significantly highly expressed in the autolysis group and stably lowly expressed in the control group, while the expression pattern of ornithine was completely opposite to that of the 3 metabolites. Pearson correlation analysis showed that there were extremely significant positive correlations between cysteine, citrulline and tryptophan (P<0.01), while all 3 showed significant negative correlations with ornithine(P<0.05). Enrichment analysis was performed on the significantly different amino acid metabolites. The results showed that the potential core highly enriched pathway in the autolysis of Coprinellus micaceus was the amino acid biosynthesis pathway, the sub-core highly enriched pathway was the biosynthesis of plant secondary metabolites and the moderately enriched pathways included arginine biosynthesis, glycine, serine and threonine metabolism,glutathione metabolism, 2-oxocarboxylic acid metabolism, central carbon metabolism in cancer, aminoacyl-tRNA biosynthesis, D-amino acid metabolism, protein digestion and absorption, and cofactor biosynthesis.

Ornithine, tryptophan, citrulline and cysteine are screen and identify as the key differential metabolites in the autolysis process of Coprinellus micaceus. These 4 kinds of amino acid differential metabolites can synergistically regulate the autolysis process of Coprinellus micaceus through multiple potential pathways. The results of this study can provide data support and scientific basis for the preservation and storage of macrofungi, optimization of processing techniques, and comprehensive development and utilization of resources.

To evaluate the risk of pesticide residues in Fragaria ananassa, and analyze the correlation between pesticide residues and the quality of Fragaria ananassa.

A total of 156 Fragaria ananassa samples were analyzed for pesticide residues. Based on the acquired pesticide residue data in Fragaria ananassa samples, the acute dietary risk of the target fruit was assessed by applying relevant maximum residue limits and dietary exposure assessment methodologies. Meanwhile, key quality parameters of the Fragaria ananassa-including vitamin C (VC), soluble sugar, titratable acid, pectin, solids and hardness were determined. The correlation between detected pesticide residues and these quality parameters was then analyzed.

A total of 19 pesticide residues were detected among the 104 kinds of target pesticides across 156 sample batches.Pesticide-free samples accounted for 24.36% of the total, while samples containing multiple pesticide residues (≥3 types) represented 15.39%. Among the detected compounds, the plant growth regulator chlormequat showed the highest residual level, with a maximum concentration of 0.408 mg/kg and a detection rate of 46.15%. Among fungicides, boscalid had the highest detection rate (21.79%). Spirodiclofen was the insecticide with the highest detection rate among insecticides (12.18%). Notably, the pesticides with insecticidal effects detected had not been registered on Fragaria ananassa. The acute dietary intake risk was below 1. VC content was positively correlated with chlormequat. Soluble sugar showed a positive correlation with procymidone, positive correlation with carbendazim, and a negative correlation with prochloraz. Titratable acid was negatively correlated with chlorantraniliprole, dinotefuran and trifloxystrobin. Pectin content was positively correlated with chlormequat, while total solids were negatively correlated with prochloraz. Hardness exhibited no significant correlation with any pesticide residues. The detection rate of pesticide residues in Fragaria ananassa was high, with a wide variety of residues identified. Both cypermethrin and dimethomorph were found to exceed the standard limits (0.64%),however, no short term dietary intake risk was observed. Appropriate application of the plant growth regulator chlormequat had a positive effect on the VC content of Fragaria ananassa. But chlormequat was not registered for Fragaria ananassa, and further screening of alternative agents was required.

This study assesses the dietary risk of pesticide residues in Fragaria ananassa and investigates their association with key nutritional quality indicators. The integrated safety-quality assessment framework established can be extended to other high-value produce, providing practical value for guiding evidence-based pesticide application and enhancing the overall quality and safety of agricultural products.

To establish a compound-specific isotope profiling method by liquid chromatography-high-resolution mass spectrometry (LC-HRMS) for identify caffeine and lovastatin derived from natural extraction, chemical synthesis and bioengineered fermentation in food matrices.

Waters XBridge BEH C₁₈ column (250 mm×4.6 mm, 5 μm) coupled with a mild elution gradient was used to moderately broaden the chromatographic elution window of target compounds. A quadrupole-orbitrap mass spectrometer operated at a resolution of 140000 full width at half maximum (FWHM) was used to continuously acquire the complete isotopic peaks of target molecules at no fewer than 20 non-equidistant time points within each chromatographic peak. During data processing, a theoretical correction model was applied to subtract heteroatom isotope contributions. Grubbs’outlier test and the pruned exact linear time (PELT) change-point detection algorithm were then used to quantify intra-peak isotopic heterogeneity and stepwise shifts. Full-elution deconvolution was further used to construct a two-dimensional isotope landscape model of the food matrix.

Caffeine from natural tea sources, chemical synthesis and bioengineered fermentation, as well as lovastatin from natural red-yeast fermentation and pharmaceutical-grade sources, showed distinct baseline isotopic fingerprints. In simulated adulteration systems,when exogenous synthetic substances accounted for 10% of the total target compound, the PELT algorithm accurately detected isotope-ratio change points at the P<0.01 confidence level; When the proportion was greater than or equal to 20%, stepwise transition points were reliably localized. The adulteration proportions back-calculated using the isotope mass-balance model showed relative deviations within ±15%. Over the concentration range of 0.1–10.0 μg/mL, the 5 consecutive days of testing gave an inter-day relative standard deviation of 0.8% for δ¹³C, with a maximum systematic bias of +0.8‰, demonstrating high precision and strong resistance to matrix interference.

The multidimensional isotope-profile time-series method established in this study enables qualitative differentiation between natural and artificially synthesize forms of the same molecule by exploiting chromatographic isotope fractionation without requiring complete chromatographic separation. This approach provides a feasible technical solution for resolving source-identification challenges involving substances with overlapping natural occurrence and artificial addition, and offers a methodological reference for improving food safety regulatory strategies.

To establish a quantitative analysis method for determining illegally added uric acid-lowering substances in food by ultra performance liquid chromatography-tandem mass spectrometry.

The sample was extracted with methanol and 5% methanol solution as the extraction solvent, and extracted by ultrasound, and then separated on a C₁₈ column with a gradient elution of 0.1% form acid aqueous solution and methanol as the mobile phase. The detection was performed using multiple reaction monitoring (MRM) mode of mass spectrometry, and quantification was done by external standard method.

In the solvent curve such as allopurinol, colchicine, topiroxostat, lesinurad and tranilast all showed linear correlation coefficients of r>0.999 in the range of 20–400 ng/mL, while risperidone, fenofibrate, febuxostat, probenecid and benzbromarone showed linear correlation coefficients of r>0.999 in the range of 2–40 ng/mL. The recovery rates ranged from 81.62% to 109.61% within 3 levels in 5 kinds of matrices such as tablets (compressed candy tablets), liquid beverage, powdered beverage,pollen and effervescent tablet and the relative standard deviations (RSDs) were 1.0% to 8.6% (n=6).

This method has high accuracy, good precision, high reproducibility and good applicability between instruments, and can meet the needs of qualitative and analysis of allopurinol and other 10 kinds of uric acid-lowering compounds in food.

To established a method for the simultaneous determination of 18 kinds of illegally added chemical components in uric-acid-lowering health food by ultra performance liquid chromatography.

The samples were extracted by methanol (with 0.1% formic acid) ultrasonic extraction, the separation was executed on an Phenomenex Luna ®Omega C₁₈ column (2.1 mm×100 mm, 1.6 μm), using methanol (A)-acetonitrile (B)-0.2% formic acid aqueous solution (C) as the mobile phase for gradient elution, and detected by diode array detector.

This method effectively distinguishes between salicylic acid and aspirin and the results showed that the 18 kinds of uric-acid-lowering components had good linearity in the linear range with the correlation coefficients greater than or equal to 0.9995; the limits of detection ranged from 2.0–112.8 mg/kg, the average recoveries ranged from 98.5%–110.6%, and the relative standard deviations ranged from 0.2%–4.4%. The method was applied to screen 35 batches of samples, 4 batches of unlabeled components were detected, 2 batch detected diclofenac, 1 batch detected piroxicam and 1 batch detected prednisone acetate.

The method is easy to operate, has good selectivity,sensitivity and accuracy, and can be used for the determi nation of illegally added drugs of uric-acid-lowering components in health food.

To establish a method for the determination of illegal additive caramel in Mume fructus by high performance liquid chromatography.

After the sample was extracted with water, ethanol was added for precipitation, the supernatant was discarded, and the sample was reconstituted with water and filtered. Luna SCX 100 Å (250 mm×4.6 mm, 5 μm) chromatography column was selected. The 10 mmol/L sodium dihydrogen phosphate was used as the mobile phase for isocratic elution and detected by a diode array detector.

Caramel exhibited a good linear relationship with peak area within the range of 0.0243–2.4300 mg/mL (r=0.9999);the limit of detection was 0.10 mg/kg; the limit of quantitation was 0.19 mg/kg; the average recovery rate was 90.1%,and the relative standard deviation was 1.8% (n=6).

This method has good sensitivity and high recovery rate, and is suitable for the detection of illegal additive caramel in Mume fructus.

To investigate the quality and safety status of commercially available seasoned flour products in Yueyang City, in 2025, and to elucidate their quality control practicess and risk characteristics.

A total of 70 batches of commercially available samples were collected from Yueyang City, Hunan Province. The 11 parameters, including acid value, peroxide value, preservatives, sweeteners and microbiological indicators, were analyzed in accordance with national food safety standards. Furthermore, the quality and safety profiles were evaluated in conjunction with packaging forms and shelf-life characteristics.

The market for seasoned flour products exhibited structural characteristic of “lightweight packaging and medium-to-long shelf life”. Pre-packaged products accounted for 64.29% of the total, with specifications of 25–50 g dominating the mainstream market, and products with a shelf life of 150 days representing 72.86%. Traditional preservatives (benzoic acid, sorbic acid, and dehydroacetic acid) were not detected in any samples. However, the issue of excessive sweetener levels was prominent: The unqualified rates for sodium cyclamate and sucralose were 1.43% and 5.71%, respectively. And all the trichlorosucrose unqualified samples were filamentous or rod-shaped products. Microbial contamination was mainly indicated by the total number of colonies, with a detection rate of 38.57% and an unqualified rate of 2.86%.The detection rates of coliform bacteria and mold were both 1.43% and did not exceed the standards. The detected samples were completely consistent with the samples with total colony counts.

The traditional preservatives in the seasoned flour products sell in Yueyang City are well controlled, but the excessive use of sweeteners and the problem of microbial contamination still exist. The product form and the dosage of additives show a potential process correlation.

To establish a method for the simultaneous determination of 9 kinds of food additives in foods by ultra performance liquid chromatography.

The samples were subjected to ultrasonic extraction with water, purified by a PWA-2 solid-phase extraction cartridge, and then separated on a Poroshell 120 EC-C₁₈ column (150 mm×3.0 mm, 2.7 μm) under gradient elution using a mobile phase composed of 25 mmol/L potassium dihydrogen phosphate solution and acetonitrile. Detection was carried out at 215 nm.

The results showed good linearity for the 9 kinds of analytes in the mass concentration range of 2.0–100.0 mg/L, with correlation coefficients (r²) not less than 0.999. The limits of detection and limits of quantitation ranged from 0.0025 to 0.0050 g/kg and from 0.005 to 0.010 g/kg, respectively. Recovery experiments were performed at low, medium and high spiked levels in 4 kinds of representative matrices (tea beverage, sausage, milk, red wine). The average recoveries were 80%–118%, with relative standard deviations in the range of 2.8%–8.5% (n=6).

The method exhibited high sensitivity, good reproducibility and high accuracy, and is applicable for the simultaneous determination of 9 kinds of food additives,including tannic acid, in food matrices.

To establish a method to determine the quality of safflower yellow in different manufacturers by high performance liquid chromatography (HPLC) fingerprint chromatogram method, and perfect the quality evaluation system of safflower yellow extract.

HPLC analysis was carried out on a C₁₈ chromatographic column (250 mm×4.6 mm, 5 μm). The mobile phase consisted of acetonitrile-0.05% trifluoroacetic acid aqueous solution with gradient elution. The flow rate was set at 1.0 mL/min, column temperature at 30 ℃,detection wavelength at 266 nm, and injection volume at 10 μL. The 16 batches of safflower yellow extract were systematically classified and analyzed via similarity evaluation, cluster analysis and principal component analysis;meanwhile, the content of hydroxysafflor yellow A was determined.

The 11 common characteristic peaks were identified in safflower yellow extract, and 6 of these peaks were assigned. Cluster analysis and principal component analysis demonstrated distinct classification differences among samples from different manufacturers.Orthogonal partial least squares-discriminant analysis (OPLS-DA) screened out 5 major marker components with variable importance in the projection (VIP) values>1; these components exhibited significant fluctuations in products from different manufacturers and could serve as key quality indicators. In terms of hydroxysafflor yellow A content,the quality of commercially available safflower yellow extract was uneven, which might be attributed to the planting environment of raw materials, harvesting and processing techniques, as well as storage conditions.

This study established a comprehensive quality evaluation system combining HPLC fingerprint analysis, chemometrics,and marker component quantification, which provides a scientific basis for refining the quality evaluation system and revising the quality standards of safflower yellow extract.

To investigate the amino acid composition characteristics and nutritional value of Cyperus esculentus from 11 provinces and autonomous regions in China (Xinjiang, Hebei, Henan, Shandong, Hunan, Ningxia,Yunnan, Inner Mongolia, Heilongjiang, Liaoning and Jilin), and establish a geolocation model based on amino acid composition.

Amino acid analyzers were used to test Cyperus esculentus samples from different varieties across these 11 provinces and autonomous regions, analyzing the effects of origin and varying climatic conditions on amino acid content. From a nutritional perspective, the nutritional value of Cyperus esculentus amino acids across the 11 provinces and autonomous regions was comprehensively evaluated through analysis of essential amino acids,branched-chain amino acid composition and amino acid scoring results.

Cyperus esculentus exhibited a rich variety of amino acids, with essential amino acids accounting for 24%–36% and branched-chain amino acids ranging from 12.02%–17.43%. Amino acid scoring indicated that methionine was the primary limiting amino acid in Cyperus esculentus across all 11 provinces and autonomous regions. In actual consumption, it was recommended to address methionine deficiency through dietary combinations or nutritional fortification. Under the subtropical monsoon climate of Southwest Asia, the levels of glutamic acid and aspartic were significantly higher than under other climatic conditions. Using chemometric software, 3 kinds of models—K-nearest neighbor algorithm (KNN), partial least squares discriminant analysis (PLS-DA) and support vector machine (SVM)—were applied for origin tracing. The KNN model demonstrated the best performance, achieving a training set recognition rate of 96.97% and a cross-validation recognition rate of 98.99%.

This study investigates amino acid content variations in Cyperus esculentus across different provinces and autonomous regions, providing a reference for Cyperus esculentus cultivation and subsequent industrialization of Cyperus esculentus products.

To investigate the effects of added vitamins and minerals on the stability of full-nutrition,foods-for-special-medical-purposes emulsions based on peanut oil bodies.

Prepared a peanut oil body-based, full-nutrition, foods-for-special-medical-purposes emulsion with an energy density of 1.0 kcal/mL using the natural emulsifying structure of peanut oil bodies, and evaluated the effects of vitamins and minerals on emulsion stability by particle size, zeta potential and multiple light scattering analyses, as well as examined changes in stability and appearance quality of each emulsion group before and after sterilization.

The addition of vitamins or minerals did not induce obvious heat-induced aggregation in peanut oil body emulsions; in particular, in the vitamin-fortified group, the droplet size increased by only 0.49% after sterilization. Emulsions with added minerals exhibited good storage stability, with creaming index values after 7 d of storage all below 1.0%. However, after sterilization, emulsions containing minerals showed a pronounced change in color (ΔE^*>20), which had a certain impact on sensory quality.

The vitamin-and mineral-enriched peanut oil body-based complete nutritional emulsion for special medical foods exhibits exceptional stability, providing a reference for the processing and utilization of oil body-based in FSMP foods.

To construct a fluorescent biosensor composed of 2’-fluoro-substituted nucleic acid aptamer (2’F-Apt) and graphene oxide (GO) for the highly sensitive and specific detection of Staphylococcus aureus in prepackaged foods.

The biosensor was fabricated via non-covalent adsorption and assembly between 2’F-Apt and GO. The fluorescence of the aptamer was quenched by GO. In the presence of target bacteria, 2’F-Apt specifically bound to surface proteins of the bacteria and detached from GO, resulting in the recovery of fluorescence signal, which enabled the quantitative detection of samples.

Compared with unmodified nucleic acids,2’-fluoro substitution reduced the conformational constraints of nucleic acid strands and improved molecular flexibility. It also increased binding sites and specific surface area, strengthened the interaction between 2’F-Apt and GO, effectively inhibited non-specific dissociation and reduced false-positive results. Meanwhile, the target recognition capability and detection sensitivity were enhanced. The test results showed that the linear detection range of the 2’F-Apt/GO biosensor for Staphylococcus aureus was 10 to 10⁹ CFU/mL, with a limit of detection of 5 CFU/mL, presenting excellent detection performance.

The biosensor constructes in this study features simple preparation, good universality and high sensitivity, and can be applied to the rapid detection of Staphylococcus aureus in prepackaged foods.

To explore the impact of different storage methods on the volatile components and quality of Lycium chinensis, and screen suitable short-term storage conditions.

Taking fresh wolfberry fruit as a control, 3 kinds of storage treatments were set up: Room temperature, low temperature (4 ℃) and freezing. Gas chromatography-ion mobility spectroscopy technology was used to identify volatile components, and the content of polysaccharides, total phenols, carotenoids, malondialdehyde (MDA) and sensory quality were determined.Combined with orthogonal partial least squares-discriminant analysis and Pearson correlation analysis, the correlation between component changes and quality was revealed.

A total of 52 kinds of volatile components were identified, among which alcohols and esters were characteristic aroma substances, which were significantly positively correlated with polysaccharides, total phenols, carotenoids, color and taste, and significantly negatively correlated with MDA; storage at room temperature promoted the accumulation of aldehydes and ketones, increased MDA, and significantly deteriorated nutritional and sensory quality; low-temperature storage could effectively inhibit the deterioration process. The volatile components were highly similar to fresh fruits. The retention rates of total phenols and carotenoids reached 89.22% and 85.72% respectively, and the sensory quality was the best; frozen storage caused serious aroma loss due to ice crystal damage, and the quality declined significantly.

The 4 ℃ low temperature storage can significantly inhibit lipid peroxidation and aroma degradation, which is an ideal method for short-term storage of Lycium chinensis.

To investigate the pollution status of 6 kinds of metal elements in different categories of vegetables sold in Xingtai Area, and assess the health risks to the population.

Microwave digestion was performed on 296 vegetable samples purchased from local markets, and the samples were analyzed by inductively coupled plasma mass spectrometry and atomic fluorescence spectrometry. The pollution levels of the 6 kinds of metal elements in the vegetables were evaluated using the single-factor pollution index and the Nemerow comprehensive pollution index. The health risks associated with residents’ dietary intake of these metals were assessed by the target hazard quotient (THQ) and total target hazard quotient (TTHQ) methods.

Chromium had the highest detection rate among the metal elements in vegetables, reaching 85.1%, with an average content of 0.1090 mg/kg and an exceedance rate of 1.7%. Among different categories of vegetables, aquatic vegetables showed the highest metal chromium content, with an average of 0.318 mg/kg and an exceedance rate of 3.7%. Correlation analysis revealed a highly significant positive correlation between chromium and nickel (r=0.629, P<0.01). In addition, pairwise associated relationships were observed between chromium and plumbum (r=0.460), nickel and plumbum (r=0.435),and cadmium and chromium (r=0.403). The Nemerow comprehensive pollution index ranged from 0.011 to 0.636 across the 8 vegetable categories, indicating an overall “excellent” level of metal pollution. Aquatic vegetables exhibited relatively high combined heavy metal risks, with TTHQ values of 1.4571, 1.2359 and 0.9857 for children,young and middle-aged adults and the elderly, respectively.

Metallic elements are detected at relatively high rates in vegetables sold in Xingtai, and aquatic vegetables may pose a certain exposure risk to human health.Meanwhile, children face significantly higher health risks from metal exposure compared with adults.

To establish a method for concurrent qualitative screening of 6 kinds of new phenylethylamine psychoactive substances in apple juice by liquid chromatography-quadrupole-time of flight mass spectrometry.

The samples were extracted with 10 mL acetonitrile, purified with C₁₈ powder, and separated on a C₁₈ column (100 mm×2.1 mm, 2.7 μm). The 10 mmol/L ammonium acetate aqueous solution (0.1% formic acid) and acetonitrile was as mobile phase, and the elution method was gradient elution. Mass spectrometry methods included electrospray ionization, positive ion scanning and information-dependent acquisition (IDA) mode detection. Screening was conducted by considering multiple factors, including the mass deviation, retention time,isotope distribution characteristics and similarity to the secondary spectrum library of the target signal.

The 6 kinds of targets showed good linearity (0.1–50.0 μg/L, r>0.9990) with matrix effects was all less than 20%, which could be classified as weak matrix effects. The limit of detection was 5.0 μg/L. The comprehensive scores of the qualitative screening were all above 90 points, meeting the requirements for qualitative confirmation.

The method is simple, rapid and sensitive, and can be used for the qualitative screening and detection of 6 kinds of new phenylethylamine psychoactive substances in apple juice.

To investigate the characteristics of pesticide residue contamination in commercially available vegetables in Shaanxi Province and assess the dietary risk of local residents through vegetable consumption.

Based on the monitoring data of 25 kinds of pesticide residues in 765 samples of 8 major categories of commercially available vegetables from 10 cities in Shaanxi Province from 2022 to 2024, the pesticide residue contamination was investigated from different aspects such as different pesticide varieties, different vegetable species, different regional distributions and utilization of multiple pesticides. Acute and chronic dietary intake risk assessment (DIRA) was conducted and the overall risk level was determined through the index of food safety (IFS).

The 23 kinds of pesticide residues were detected in vegetable samples, with an overall detection rate of 58.17% and an exceeding rate of 2.35%. Prohibited and restricted pesticides were detected in 24 samples, among which dimethoate, omethoate and phorate were found to exceed the maximum residue limits upon detection. The detection rate of individual indicators ranged from 0.13% to 25.49% and the exceeding rates ranged from 0.13% to 0.65%. Leafy vegetables (74.31%) had the highest detection rate and the co-use of multiple pesticides was the most prominent. Exceedance samples were found in leafy vegetables (4.74%), bulb vegetables (3.51%) and fruit vegetables(3.01%). The extreme values of detection in the Shannan region were relatively high and the Guanzhong region contributed 72.22% of the exceedance cases in the province. The percentage of acute reference dose (%ARfD) of omethoate was 399.67%, while the %ARfD and percentage of acceptable daily intake (%ADI) of the other evaluated pesticides were all less than 100%. The IFS of each individual pesticide was less than 1 and the mean index of food safety () of vegetables was less than 1.

The pesticide residues in commercially available vegetables in Shaanxi Province show a high detection rate and a low exceeding rate, and the phenomenon of multiple pesticide co-use in leafy vegetables is quite prominent. Except for omethoate, the acute and chronic dietary exposure risks of other pesticides are within acceptable limits. The overall safety risk of vegetables is controllable. The illegal use of prohibited and restricted pesticides and the acute dietary exposure risk of omethoate are the main factors affecting vegetable quality. The findings of this study may provide data support for refining local regulatory strategies and implementing dietary risk warnings for residents.

To establish a method for the determination of 16 kinds of fluorinated liquid-crystal compounds in meats including pork, beef, lamb and chicken by gas chromatography-tandem mass spectrometry.

After ultrasonic extraction with N-hexane/dichloromethane (1:1, V:V), the samples were purified via Florisil solid-phase extraction column, and then separated by DB-5MS gas chromatographic column. Atmospheric pressure chemical ionization source in positive ion mode was adopted, and multiple reaction monitoring was performed by gas chromatography-tandem mass spectrometry with internal standard method for quantitative analysis.

The linear relationship of the 16 kinds of fluorinated liquid-crystal compounds was good within the range of 0.1–50.0 μg/L, and the correlation coefficient was greater than 0.995. The limits of detection were 0.02–0.18 μg/kg, and the limits of quantitation were 0.07–0.59 μg/kg. At the spiked levels of 1.0, 10.0 and 50.0 μg/kg, the recoveries ranged from 86.3% to 113.7%, the relative standard deviations were 1.4%–11.2%.

The method is simple, quick, accurate and sensitive. It is suitable for the confirmation and quantification of fluorinated liquid-crystal compounds in meat samples. This method can provide a reference and technical support for the quality and safety screening of meat samples.