Objective To study the change of benzoic acid content in water extract of Paeoniae Radix Alba after decocting, and the influence of different decocting time on the content of benzoic acid. Methods The raw materials were decocted separately or in combination, and concentrate to a density of 1.15-1.20, the content of benzoic acid in the water extract after decocting and concentrating was determined by high performance liquid chromatography. Results Benzoic acid content was not detected (limit of quantification was 0.01 g/kg) in Paeoniae Radix Alba, the benzoic acid content in concentrated liquid of paeony increased to 2.91-3.77 g/kg after single decocting, and the benzoic acid content after two-stage decocting ranged from 3.26 g/kg to 4.02 g/kg. The content of benzoic acid in the mixed concentrate containing Paeoniae Radix Alba was 0.542 g/kg. Benzoic acid was not detected in others. Conclusion The content of benzoic acid in water extract of Paeoniae Radix Alba increased after high temperature decocting, and it's proportional to time. Therefore, when preparing food or health products with Paeoniae Radix Alba as the main raw material, attention should be paid to the control of decocting temperature and time, and the factory inspection of this item should be increased to prevent the harm caused by high content of benzoic acid.

Objective To establish a vegetable safety risk prediction model based on the particle swarm optimization (PSO) algorithm and the stacked generalization (Stacking) model, and to predict the sampling results of fenthion in vegetables sold in Shanghai. Methods Based on the sampling data of fenthion in vegetables sold in Shanghai from 2021 to 2023, task type, sampling area, sampling link, sampling place, sampling month, testing institution, and vegetable variety were selected as feature variables. The target variable was whether the sampling results for fenthion in vegetables were qualified. The PSO-Stacking prediction model was constructed using ten-fold cross-validation to select effective machine learning models and resampling methods and optimized the model parameters using the PSO algorithm. Results Fenthion-positive samples were found in 55 out of 3889 vegetable samples, with an overall failure rate of 1.4%. Bean vegetables had the highest rate at 2.3%, followed by eggplant and fruiting vegetables at 0.2%. The base models were obtained through screening, including Random Forest (RF), categorical boosting (CatBoost), gradient boosting (GB), extreme gradient Boosting (XGBoost), and light gradient boosting machine (LGBM). The best resampling technique was adaptive synthetic sampling (ADASYN). The PSO-Stacking model achieved the highest precision (0.91), recall (0.83), F1 score (0.87), and area under the curve (AUC) value (0.91) on the test set. Conclusion The PSO-Stacking model effectively addresses imbalanced food safety sampling data, accurately predicts the unqualified fenthion samples in vegetables, and provides technical support for vegetable supervision, sampling and risk warning.

Objective To investigate the effects of cured meat products on the gut microbiota of mice based on high-throughput sequencing technology. Methods Mice were randomly divided into 3 groups, with half male and half female. Each group consisted of 12 mice, including the control group, the low-dose group, and the high-dose group, and feeding for a period of time. The feces and intestinal content of mice were collected for microbial structure research, and the effects of consuming cured meat on the gut microbiota of mice was analyzed. Results There was no significant difference in total bacterial count between the control group and the experimental group (P>0.05), however the changes in the number of Gram negative bacterial colonies and Gram positive bacterial colonies were significant (P<0.05). The number of lactic acid bacteria in the high-dose group showed significant changes (P<0.05), while the low-dose group had no significant changes (P>0.05). The high-throughput sequencing analysis of 16S ribosomal RNA (16S rRNA) in the gut microbiota of mice showed that the alpha diversity of the gut microbiota in the high-dose group was significantly lower than that in the control group (P<0.05) starting from the 4th week of the experiment, and starting from 12th week, that of the low-dose group also began to decrease significantly. The types of bacteria that changed in the gut microbiota of mice in the high-dose and low-dose groups were almost the same, with an increase in the proportion of Gram positive bacteria, an increase in the relative abundance of Bacteroidetes and Spirochetes, and a decrease in the relative abundance of Lactobacillus. Starting from the 4th week of the experiment, there were differences in metabolic pathways between each group of mice in terms of glucose metabolism, amino acid metabolism, protein metabolism, etc. The differences were self-compensated at the 8th week, and significant differences were observed between the high-dose and low-dose groups and the control group at the 12th week (P<0.05). The differences between the high-dose and low-dose groups increased. Conclusion Continuous intake of cured meat products can change the structure and composition of the gut microbiota, cause imbalance in the gut microbiota structure, and alter the colonization of beneficial and harmful microbiota in the intestine of mice, which may be related to the induction of intestinal diseases.

Objective To study the effects of deep eutectic solvent (DES) on the absorbance of tea polysaccharide by visible spectrophotometry, and establish a fast and efficient method for the determination of tea polysaccharide. Methods Choline chloride/DL-tartaric acid was used as the extraction solvent of tea polysaccharide. The influence of DES on the determination of tea polysaccharide content in anthrone sulfuric acid and phenol-sulfuric acid 2 kinds of detection methods was investigated. The linear relationship, precision, stability, repeatability and standard recovery rate of the 2 kinds of detection methods were compared. Results The best method for the determination of tea polysaccharides was phenol-sulfuric acid method, the optimal detection wavelength was 484 nm, and the absorbance had a good linear relationship with glucose concentration between 20 and 100 μg/mL. The precision relative standard deviation (RSD) of this method was 0.10%, the stability RSD was 0.00%, the repeatability RSD was 2.40%, and the recovery rate was 94.25%-111.19%, and the content of tea polysaccharide was 54.76 mg/g. Conclusion Phenol-sulfuric acid method is suitable for the determination of tea polysaccharide in tea with DES as extraction solvent.

Objective To establish a method for simultaneous determination the content of 4 kinds of human milk oligosaccharides [2'--fucosyllactose (2'-FL), 3'-sialic acid (3'-SL), 6'-sialic acid (6'-SL) and lactose-N-neotetraose (LNnT)] in milk powder by liquid chromatography-fluorescence method. Methods The samples were dissolved in water, enzymolized with amyloglucosidase or β-galactosidase, derived with 2-aminobenzamide (2-AB) and 2-methylpyridine borane (2-PB), and separated by amide bonding column, detected by fluorescence detector, and quantitated by internal standard methods. Results The 4 kinds of milk oligosaccharides had a good linear relationship in the concentration range of 10-600 μg/mL, and the correlation coefficients (r²) were more than 0.999. The limits of detection and quantification of 4 kinds of milk oligosaccharides were 0.94-2.31 mg/100 g and 3.12-7.69 mg/100 g, respectively; the recovery rates of 4 kinds of milk oligosaccharides were 97.7%-101.5%, and the relative standard deviations (RSD) (n=7) were 0.53%-3.09%. Conclusion This method does not have high requirements for people, equipments and environment for determining the content of 4 kinds of milk oligosaccharides in milk powder. The pre-treatment operation is simple, and it has good accuracy and precision. It can provide a reference for the quality control method of human milk oligosaccharides in milk powder.

Objective To establish a method for the determination of 25 kinds of illegal additives in candy by dispersive solid phase microextraction extraction coupled with ultra performance liquid chromatography-tandem mass spectrometry. Methods The samples were extracted with 50% methanol water, purified by dispersive solid phase microextraction extraction and separated by ACQUITY UPLC TSS T3 column. The samples were then eluted with ammonium formate aqueous solution and ammonium acetonitrile as mobile phase by gradient elution. The samples were determined by ultra performance liquid chromatography-tandem mass spectrometry and quantified by external standard method. Results The results showed that the 25 kinds of illegal additives had good linearity in the range of 2.00 to 50.00 µg/L with a correlation coefficient (r²) greater than 0.99, recoveries were between 65.1% and 99.3%, relative standard deviations were 1.1% to 5.0%, and limit of detection was 0.05 mg/kg and limit of quantification was 0.10 mg/kg. The method was applied to the detection of 105 batches of samples, in which one batch of compressed candy was found to contain xinlisita, and two batches of candy were found to contain dipropylphenidate. Conclusion The method is purified by dispersive solid phase microextraction extraction and detected by ultra performance liquid chromatography-tandem mass spectrometry. The method has good accuracy and high sensitivity, and can meet the detection requirements of 25 kinds of illegal additives in candy.

At present, the demand for acaricides in agricultural production in China ranks second only to insecticides. As an important chemical pollutant affecting the safety of agricultural products, acaricides, represented by heterocyclic compounds, have relatively stable structures, long half lives, are not easily degraded, and are more likely to remain on the surface or inside of food, causing serious food safety problems. The development of economically effective detection methods for heterocyclic acaricides has become a current research trend, which is of great significance for ensuring the safety of public vegetable baskets, promoting green ecological agriculture, and advancing high-quality agricultural development. Immunoassay methods are widely used in the field of pesticide residue detection due to their fast, simple, efficient, and sensitive characteristics. This paper reviewed the research progress of immunological analysis methods for heterocyclic acaricides pesticides from the aspects of synthesis of haptens, preparation of antibodies, and their detection applications in agricultural product matrices, analyzed the challenges and future development prospects of immunoassay methods, which have certain reference value for the detection of heterocyclic acaricides residues.

Objective To investigate the effects of different storage methods on the quality safety of high-moisture harvested Zea mays L.. Methods The Zhengdan 958 (ZD958) Zea mays L. variety was selected for the experiment, and the Zea mays L. harvested under the same moisture content was stored as ear Zea mays L. and grain Zea mays L.. Changes in fungi species, quantity, and mycotoxin content were measured. Results Predominant fungi during Zea mays L. storage were Fusarium, Aspergillus, and Penicillium. In the early stage of storage, the dominant fungal genus was Fusarium, and with the extension of storage time, the dominant fungal genera changed to Aspergillus and Penicillium; with the increase of storage days, the total number of fungi in Zea mays L. stored in ear and grain storage showed a trend of first increasing and then decreasing. The number of fungi in Zea mays L. stored in ears was significantly lower than that in Zea mays L. stored in grains (P<0.05). During the storage period of 10-100 days, the number of fungi in Zea mays L. stored in ears decreased by 90.3%-98.6% compared to Zea mays L. stored in grains; with the increase of storage days, except for gibberellin in Zea mays L. kernels stored in ear, the content of vomitoxin and gibberellin in Zea mays L. showed an increasing trend. The content of vomitoxin and gibberellin in Zea mays L. stored in ears was significantly lower than that in Zea mays L. stored in grains (P<0.05). And with the increase of storage days, the difference in the content of vomitoxin and gibberellin in Zea mays L. under the two storage methods increases. Conclusion After high-moisture harvesting, ear storage can reduce fungi quantity and mycotoxin content, ensuring the quality safety of Zea mays L..

Carthamu stinctorius L. serves as a viable raw material for health supplements but is not classified as a general food item. It is rich in bioactive compounds such as flavonoids, alkaloids, and organic acids. Carthamu stinctorius L. exhibits significant benefits including enhancing immunity, providing antioxidant properties, maintaining healthy blood lipid and glucose levels, improving chloasma, alleviating physical fatigue, delaying aging, aiding memory improvement, and offering auxiliary protection against chemical-induced liver injury. Consequently, it has garnered considerable attention from researchers and consumers both domestically and internationally. Currently, Carthamu stinctorius L. is extensively utilized in health supplements within our country; however, there is a lack of systematic analysis regarding its application. This paper aims to examine the current status of Carthamu stinctorius L. is application in health supplements, the regulatory framework for its compliant use, and the factors influencing the efficacy of its primary active components. Additionally, it delves into the principal health functions and mechanisms of Carthamu stinctorius L., with the objective of providing insights for compliant utilization and future research and development of Carthamu stinctorius L. in the health supplement industry within our country.

Objective To establish a method for rapid determination of chromium content in aluminum food packaging based on fiber laser induced breakdown spectroscopy. Methods The sensitivity and limit of detection of laser induced breakdown spectroscopy and flame atomic absorption spectrometry optimized by laser pulse width, energy and baseline were evaluated with reference materials, and the 2 kinds of techniques were applied to the detection of aluminum food packaging samples, and the corresponding results were compared. Results For fiber laser induced breakdown spectroscopy, the time consumption was 2 min, the limit of detection was 5.2 μg/g, and the detected Cr content of coca cola packaging, aluminum foil paper and aluminum box were 45, 22, 21 μg/g, respectively. For flame atomic absorption spectrometry, the time consumption was 4 h, limit of detection was 7.2 μg/g, and the detected Cr content of these 3 samples were 136, 16, 14 μg/g, respectively. Conclusion This method is superior to the conventional flame atomic absorption spectrometry method in terms of analyzing speed, limit of detection and cost, and its detection results of commercial samples are similar to those of flame atomic absorption spectrometry, which proves the reliability of this method and its potential applicability in analysis tasks of limited time and large sample quantity.