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

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

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

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

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

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

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

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

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

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