Objective To establish the detection of 172 kinds of pesticide residues in brown sugar by QuEChERS-gas chromatography-tandem mass spectrometry (GC-MS/MS). Methods The samples were fully dissolved in ultrapure water and extracted by high-speed homogenization of n-hexane, nitrogen blowing and concentration, and purified by QuEChERS method, and the data was collected in selective reaction monitoring mode by GC-MS/MS detection technology, and quantitatively detected by matrix curve and solvent curve. Results The 172 kinds of pesticides had a good linear relationship in the linear range of 10-200 ng/mL, and the linear correlation coefficient was between 0.9962 and 0.9999, the limit of quantification of the method was 0.01 mg/kg, performed 6 repeated spiked experiments at concentrations 1, 2, and 10 times the limit of quantification each, the recovery rate of spikes was between 71.0%-113.0%, and the relative standard deviation (n=6) was 0.49%-17.00%. Conclusion This method can detect hundreds of pesticides in one injection, which is fast, simple, high-throughput and economical, and is suitable for the detection of a variety of pesticide residues in brown sugar.

Objective To achieve rapid and non-destructive determination of aflatoxin B₁ (AFB₁) content in Triticum aestivum L. kernels by establishing a quantitative prediction model based on near-infrared spectroscopy technology. Methods The reflectance spectra of Triticum aestivum L. samples in the wavelength range of 900-1700 nm were collected, and the AFB₁ content in Triticum aestivum L. was determined by high performance liquid chromatography. The raw spectral data of the Triticum aestivum L. samples were subjected to preprocessing, and the feature wavelengths were extracted in order to establish a prediction model. A model for predicting the AFB₁ content was developed using a back propagation neural network (BPNN), random forest (RF), and support vector machine (SVM), the results of this model were compared with those of a full-wavelength modelling approach. Results The SVM model constructed following the application of multiplicative scatter correction (MSC) and competitive adaptive reweighted sampling (CARS) processing demonstrates superior performance compared to the other models and the full-band modelling model. Conclusion The combination of the CARS algorithm and the MSC-CARS-SVM model allows for the rapid and non-destructive detection of AFB₁ content. The feasibility of using near-infrared spectroscopy for quantitative analysis of AFB₁ content has been demonstrated, and this approach can be employed to assess the quality of Triticum aestivum L. during storage.

Objective To establish a detection method for 12 kinds of nicotine pesticides in fruits by ultra performance liquid chromatography-tandem mass spectrometry coupled with cold induced liquid-liquid extraction. Methods Fruit samples were extracted using acetonitrile, and after salting out, shaking, and centrifugation, they were subjected to freeze induced liquid-liquid extraction using acetonitrile water solution for further enrichment and purification. Combined with ultra performance liquid chromatography mass spectrometry, data was collected using a multi reaction monitoring mode, and quantified using isotope internal standard method. Results The linear range of 12 kinds of nicotine compounds was 1-500 ng/mL, and the method showed good linearity (r²>0.999). The limits of detection were 2.15-3.60 μg/kg, and the method limits of quantification were 7.11-13.01 μg/kg. The recovery rates of 12 kinds of nicotine compounds were 73.1%-126.7%, and the relative standard deviations were 3.5%-13.3%. Conclusion This method is easy to operate, has high precision, and good stability, and is suitable for screening and detecting nicotine like compounds in fruit samples.

Objective To investigate the Effects of lactic acid bacteria fermentation on the sensory, physicochemical, and flavor quality of sour bamboo shoots. Methods Fresh Dendrocalamus latiflorus bamboo shoots were cut into strips and subjected to fermentation using lactic acid bacteria or natural fermentation in pure water as a control. The study investigated changes in total acidity, amino nitrogen, nitrite content, sensory evaluation, and volatile flavor compounds in sour bamboo shoots fermented with lactic acid bacteria compared to natural fermentation. Results After 60 days of fermentation, the total acidity and amino nitrogen content of the lactic acid bacteria-fermented sour bamboo shoots were 19.28 g/kg and 0.506 g/100 g, respectively, significantly higher than those of the naturally fermented sour bamboo shoots (16.14 g/kg and 0.448 g/100 g, respectively). The nitrite content of the lactic acid bacteria-fermented sour bamboo shoots was less than half that of the naturally fermented sample, with both fermentation methods yielding nitrite levels below 2.9 mg/kg. Solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) analysis detected 10 kinds of volatile flavor compounds in the lactic acid bacteria-fermented sour bamboo shoots, compared to 9 in the naturally fermented ones, with p-cresol being the primary flavor compound. The lactic acid bacteria-fermented sour bamboo shoots exhibited a uniform milky-white color, crisp texture, rich aroma and moderate acidity, achieving a sensory evaluation score of 88 points. Conclusion Sour bamboo shoots fermented with lactic acid bacteria have high sensory scores, good quality, and high food safety.

Objective To establish a rapid detection method for the simultaneous determination of 24 kinds of veterinary drug residues in pork by QuEChERS technique combined with ultra performance liquid chromatography-tandem triple quadrupole mass spectrometry (UPLC-MS/MS). Methods The samples were extracted with acidified acetonitrile, salted out by 3 g magnesium sulfate anhydrous and 2 g C₁₈ E, separated by Thermo-Fisher Hypersil GOLD aQ chromatographic column (50 mm×2.1 mm, 1.9 μm) via gradient elution of acetonitrile and 0.1% formic acid aqueous solution. The gradient elution of acetonitrile and 0.1% formic acid in aqueous solution was performed in the mode of electrospray positive ion scanning. Results The linear relationship of 24 kinds of veterinary drugs was good, and the correlation coefficients were greater than 0.9910, and the detection limit ranged from 0.2-10.0 μg/kg. The spiked recoveries varied between 70.2%-110.3%, and the relative standard deviations were 1.2%-13.8%. Conclusion The method is simple, rapid, accurate, practical, and suitable for detection of multiple veterinary drug residues in pork.

Objective To explore the effect of stir-frying and ultramicro grinding on the quality of Crataegus pinnatifida kernel. Methods The Crataegus pinnatifida kernels produced and processed by the enterprise were used as the test materials, and the Crataegus pinnatifida kernels were treated by ordinary grinding, frying-ordinary grinding and frying-ultrafine grinding combined treatment technology, and the physical properties of surface color, surface structure, water-holding capacity, oil-holding capacity, and the changes of oxidation resistance and flavonoid release were determined. Results The Crataegus pinnatifida kernel powder treated by frying and ultrafine grinding had an increased binding capacity to water, a solubility of 35.63%, an expansion force of 3.71 mL/g, and an oil-holding capacity of 2.61 g/g. The angle of repose and slip angle were reduced to 37.12° and 43.63°, respectively. The flavonoid release rate of Crataegus pinnatifida kernel powder increased from 60.47% to 71.48%, and the oxidant resistance increased by nearly 20%, which was manifested by a increase in the scavenging rates of 2,2-diazine-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) cationic radical, 1,1-diphenyl-2- picrylhydrazyl (DPPH) radicals and hydroxyl radicals. Conclusion Therefore, the combined treatment technology of frying and ultrafine grinding is a feasible processing method for Crataegus pinnatifida kernel powder. This technology can effectively improve the physicochemical properties of Crataegus pinnatifida kernel powder and increase the total flavonoid release rate. The results of this study are helpful to enhance the market value of Crataegus pinnatifida nuclear powder and promote the sustainable development of Crataegus pinnatifida industry.

Objective To study the beef quality characteristics of Pingliang red cattle. Methods The 12-13 thoracic intercostal eye muscles of A3 grade Pingliang red cattle were taken. The nutritional characteristics, tenderness and water retention of Pingliang red cattle were analyzed by measuring the protein, fat, moisture content, amino acid and fat composition, as well as the shear force and cooking loss. The sensory evaluation of raw and fried steak and rinsed meat slices were carried out respectively. The meat quality of A3 grade imported snowflake beef was compared, and the meat quality of Pingliang red cattle was comprehensively analyzed. Results There was no significant difference in crude protein, moisture and total fat content between Pingliang red cattle and imported snowflake beef (P>0.05); Pingliang red beef was rich in amino acids, and the ratio of essential amino acids to total amino acids was 0.45±0.05, which was higher than that of A3 grade imported snowflake beef (0.42±0.00); Pingliang red cattle had the advantages of low saturated fatty acid and high unsaturated fatty acid content. The fatty acid content of Pingliang red cattle was lower than that of imported snowflake beef, but the difference was not significant (P>0.05); the shear force of Pingliang red beef was (4219.10±225.29) g, which was significantly higher than that of imported snowflake beef (P<0.05). Sensory evaluation results showed that fresh Pingliang red beef was slightly lower than imported snowflake beef, but cooked Pingliang red beef scored higher, especially chewing elasticity, juiciness and aftertaste were significantly higher than imported snowflake beef (P<0.05). Conclution Pingliang red cattle A3 grade snowflakes beef can completely reach the quality level of imported snowflake beef, but the content and distribution of functional fatty acid needs to be regulated.

Objective To establish a method for the analysis of 19 kinds of metal elements in Nelumbo nucifere Gaertn. by inductively coupled plasma-mass spectrometry (ICP-MS), and to compare and analyze the metal elements content from different areas. Methods The Nelumbo nucifere Gaertn. sample was digested by microwave, and the metal elements content was determined by ICP-MS. The metal element fingerprint was drawn, and principal component analysis was performed on the metal element content using SPSS 26.0 software. Results The fingerprint of 19 kinds of metal elements in the Nelumbo nucifere Gaertn. had certain characteristics, and the content of harmful metal elements should be of concerned. Principal component analysis identified 8 main factors and identified B, S, Ca, Mn, Fe, Zn, Sr, Sb, Ba, As, and Pb as characteristic metal elements for Nelumbo nucifere Gaertn.. The correlation of 19 kinds of metal elements with the comprehensive score value of principal component analysis that were positively correlated in decreasing order were as follows: Pb, As, Ba, Zn, Sb, Mg, Cd, K, S, B, Na, Hg, Cu, Fe, Ni, and negatively correlated correlated in decreasing order were as follows: Sr, Mn, Ca, Mo. Conclusion The method is rapid, accurate and sensitive, and can be used for the simultaneous determination of the content of various metal elements in Nelumbo nucifere Gaertn.. It provides the basis for the quality control and safety evaluation of Nelumbo nucifere Gaertn..

Objective To detect and analyze the content of As, Cd, Cr, Cu, Ni and Pb in different dried Lycium barbarum L. from Nuomuhong Farm, Chaidamu, and evaluate the health risk of heavy metals in Lycium barbarum L. via the dietary route to humans. Methods The content of 6 kinds of heavy metals in Lycium barbarum L. was determined by inductively coupled plasma emission spectrometer. The pollution degree of Lycium barbarum L. heavy metals was evaluated by single factor index, mean pollution index, pollution factor analysis and Nemero's composite pollution index. The target risk factor method was used to evaluate the health risk of single and complex heavy metal intake of Lycium barbarum L. Results The single pollution index of 6 kinds of heavy metals in Lycium barbarum L. in this area was less than 1, and the comprehensive pollution index was less than 0.7, and the mean pollution index of the lock-in freshness group was less than 0.1, which was uncontaminated, and the mean pollution index of the sun-dried, hot air dried, and hang-dried groups was less than 0.2, which was a slightly contaminated state, and among them, Cu, and Cd were the main contaminating factors. Through correlation and principal component analysis, the sources of heavy metal pollution in the drying process of Lycium barbarum L. were characterized by diversified and multiple pathways, and the heavy metal content of Lycium barbarum L. that had undergone lock-in freshness treatment and hang-dried treatment had a higher safety coefficient; the single or compound heavy metals ingested by the human body through the consumption of Lycium barbarum L. did not pose a health risk to either children or adults. Conclusion The pollution degree of heavy metal of Lycium barbarum L. in this region is low, and the content is in accordance with the limited requirement of Chinese Pharmacopoeia 2020, and there is a certain effect of different drying on the heavy metal content of Lycium barbarum L., and this test can provide a reference basis for the prevention and control of heavy metal pollution of Lycium barbarum L. in the drying system.

Pyrus spp. are cherished by consumers for their unique taste and flavor, which has led to their widespread cultivation and consumption around the globe. Pesticides, an essential input for Pyrus spp. production, are vital in the prevention and control of pests and diseases; however, they also contribute to the issue of pesticide residues, which has emerged as a significant concern affecting the quality and safety of Pyrus spp. products. This paper briefly described the registered and commonly used pesticides in China's Pyrus spp. production, analyzed the contamination characteristics of pesticide residues in Pyrus spp. both domestically and internationally, discussed recent findings on the dissipation of pesticide residues in Pyrus spp., reviewed principal analysis techniques and recent advancements for their determination, including sample preparations such as solid phase extraction, dispersive solid phase extraction, multi-plug filtration cleanup, and array-thin film micro-extraction, as well as analytical procedures like triple quadrupole mass spectrometry, quadrupole-time-of-flight mass spectrometry, surface-enhanced raman scattering, and immunoassay, and offered current shortcomings and future research recommendations in this field. This review aims to provide valuable references for ongoing studies on pesticide residues in Pyrus spp.