Objective To explore the optimal fermentation process of Vatica wine and analyze its flavor substances. Methods The fermentation conditions of Vatica wine were optimized by single factor experiments and Box-Behnken response surface analysis. The effects of yeast addition amount, fermentation temperature and fermentation time on the fermentation of green plum wine were analyzed. The flavor components of green plum wine were analyzed by headspace solid-phase microextraction and gas chromatography-mass spectrometry to determine the optimal process conditions. Single-factor experiments. Results The optimal technological conditions were as follows: Fermentation temperature 25 ℃, yeast addition 0.5 g/L, fermentation time for 8 days. Among them, 25 kinds of volatile flavor substances were detected. The main flavor active ingredients were alcohols, esters, aldehydes and ketones, terpenes, etc. They accounted for 59.28%, 9.07%, 17.00% and 0.96% of flavor substances, respectively. Conclusion The Vatica wine fermented by this condition is sweet and sour and has the unique fragrance of Vatica, which provides theoretical support for the industrialization upgrading and quality improvement of Vatica wine.

Objective To establish a magnetic solid phase extraction (MSPE) approach based on covalent organic framework materials in combination with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) for the efficient determination of 9 kinds of carbamate pesticides (CPs) in Vigna unguiculata. Methods After the extraction of Vigna unguiculata samples, the novel Fe₃O₄@TAPOB-BDTB material was employed for magnetic solid-phase extraction and purification. After filtration, the samples were separated by a C₁₈ chromatographic column and quantitatively analyzed using multiple reaction monitoring in the electrospray positive ion mode. Results The established analytical methods for the 9 kinds of CPs exhibited excellent linearity within the concentration range of 0.02-100.00 μg/kg, with the determination coefficients (r²) all exceeding 0.9989. The spiked recovery rates were within the range of 80.33%-108.63%, and both the intra-day and inter-day precisions were less than 8.89%. The detection limits of the methods were 0.005-0.010 μg/kg, and the limits of quantitation were 0.02 μg/kg, which were significantly below the maximum residue limits specified in GB 2763—2021 National food safety standard-Maximum residue limits of pesticides in food and EU Regulation No 396/2005, ensuring compliance within an academic context. Conclusion The covalent organic framework materials synthesize in this study demonstrate exceptional adsorption capacity for CPs via π-π interactions and hydrogen bonding. Furthermore, the develope MSPE-HPLC-MS/MS method enables rapid, highly sensitive, and precise detection of CPs in Vigna unguiculata, thereby offering an efficient and innovative approach for monitoring pesticide residues in agricultural products.

Objective To evaluate the effects of forchlorfenuron dipping and spraying on the quality of Actinidia chinensis in Sichuan Province after flowering and determine the optimal application method. Methods At 20 days after flowering, Hongyang and Jinyan Actinidia chinensis were treated with forchlorfenuron by dipping and spraying. At maturity, fruits were harvested, and their morphological structure, texture, external quality, amino acid content, and internal nutritional quality indicators were analyzed. Results Compared to spraying, forchlorfenuron dipping could significantly increase soluble sugar and dry matter content in Jinyan Actinidia chinensis but had no significant effect on fruit longitudinal and transverse diameters, fruit shape index, amino acid content as well as other parameters. Different from Jinyan Actinidia chinensis, forchlorfenuron dipping could increase Hongyang fruit longitudinal and transverse diameters, single fruit weight, and the content of alanine and histidine. It also reduced fruit firmness and titratable acid content while improving the ascorbic acid, solid-acid ratio, dry matter, soluble sugar, soluble solids and total polyphenol content, enhancing taste and quality. Conclusion According to the results of principal component analysis, forchlorfenuron dipping is more effective than spraying in optimizing fruit morphology, softening fruit, improving taste, and enhancing the quality of both Hongyang Actinidia chinensis. Therefore, dipping is recommended as the optimal forchlorfenuron application method for the cultivation of Hongyang Actinidia chinensis, yet dipping and spraying with forchlorfenuron are both suitable for Jinyan Actinidia chinensis. This study provides technical support for the scientific and standardized use of forchlorfenuron in Sichuan Actinidia chinensis production.

Objective To establish a method to simultaneously determine the content of 5 kinds of components of Lonicera japonica Thunb. herbs from Sandao real estate area (neochlorogenic acid, chlorogenic acid, isochlorogenic acid A, isochlorogenic acid B and isochlorogenic acid C) by quantitative analysis of multi-components by single marker. Methods Phenomenex Synergi Hydro-RP80A (250 mm×4.6 mm, 4 μm) column was used with acetonitrile (A)-0.1% phosphoric acid aqueous solution (B) as mobile phase, the detection wavelength was 327 nm, the column temperature was 20 ℃, and the flow rate was 0.7 mL/min. The injection volume was 2 µL. Results The linear ranges of neochlorogenic acid, chlorogenic acid, isochlorogenic acid B, isochlorogenic acid A and isochlorogenic acid C were 0.41-16.40, 7.22-289.00, 0.21-8.50, 1.65-66.00 and 0.37-14.80 μg/mL (r≥0.9993), respectively. The average recovery rate was 95.25%-100.42%, and the relative standard deviation (RSD) of precision, repeatability and stability were less than 2.0%. The content of neochlorogenic acid, chlorogenic acid, isochlorogenic acid A, isochlorogenic acid B and isochlorogenic acid C in 25 batches of samples was determined by external standard method, and there was no significant difference between the measured values and the calculated values of quantitative analysis of multi-components by single marker method. Conclusion This method is accurate, reliable and simple for the simultaneous determination of the content of 5 kinds of compounds in Lonicera japonica Thunb., which solves the bottleneck problem of lack of reference substances in the quality control of Lonicera japonica Thunb.. The content of caffeoylquinic acid in Lonicera japonica Thunb. from different origins varies greatly, and it is necessary to further strengthen the processing of Lonicera japonica Thunb.. This study provides an important basis for the identification, quality evaluation and formulation of quality standards of Lonicera japonica Thunb..

Objective To screen salt-tolerant esterase-producing strains from yellow water and analyze their metabolic products. Methods Esterase-producing strains were isolated from yellow water and identified using morphological, physiological, biochemical and molecular biological methods. Results The 9 esterase-producing strains were screened from yellow water, among which CZ-1, CZ-5 and CZ-8 were Paenibacillus dendritiformis, CZ-9 was Paenibacillus cookii, CZ-10, CZ-13 and CZ-15 were Bacillus velezensis, and CZ-3 was Saccharomyces cerevisiae, P5-5 was Pichia manshurica. All 9 strains had good salt tolerance and could grow at pH 2.0-11.0, and 7 strains had salt tolerance up to 120 g/L. Experiments showed that when using caproic acid as the substrate, the esterifying enzyme activities of strains CZ-1, CZ-3, CZ-5, CZ-8, CZ-9, CZ-13, CZ-15 and P5-5 were 69.93, 70.62, 6.01, 67.65, 35.31, 48.51, 69.24 and 71.45 U/mL respectively, and strain CZ-10 had no esterifying enzyme activity. Gas chromatography-mass spectrometer analysis showed that 12 kinds of volatile components of alcohols, 7 kinds of volatile components of aldehydes, 1 kind of volatile component of ethers, 3 kinds of volatile components of amines, 11 kinds of volatile components of ketones, 9 kinds of volatile components of esters, 3 kinds of volatile components of acids and 22 kinds of other volatile components were detected in the fermentation broth. Conclusion The 9 esterifying enzyme-producing strains are screened from yellow water, all of which have good salt and alkali tolerance and esterifying enzyme activity. P5-5 has the highest esterifying enzyme activity and the most types of volatile components, which provides a theoretical basis for the subsequent treatment and application of yellow water.

Objective To rapidly identify the chemical components in the peel of Wogam by ultra performance liquid chromatography-tandem quadrupole electrostatic field orbital trap mass spectrometry (UPLC-QE-MS) in combination with various data analysis methods. Methods The samples were separated by Thermo Scientific Hypersil GOLD AQ (2.1 mm×100 mm, 1.9 μm) chromatographic column using solution A (0.1% formic acid-acetonitrile) and solution B (0.1% formic acid-water) as the mobile phase in a gradient elution mode. In the positive and negative ion mode, the electrical spray ion source was used to collect the signals of various chemical components in the peel of Wogam by means of one-step full scanning and two-stage ion scanning. Based on the high-resolution mass spectrometry data of traditional Chinese medicine components in the Trace Finder software and the screening network database of Compound Discoverer 3.2 software, the identification of chemical components were carried out by comparing the recognition of primary ions, major secondary ions, and other factors of the sample, as well as combining the possible cleavage pathways of the compound and consulting relevant literature reports. Through comprehensive analysis and judgment, the components were determined. Results Through literature review and comparison with high-resolution mass spectrometry data and databases, as well as compound analysis, a total of 52 compounds belonging to 11 categories were identified from the peel of Wogam, including 1 aldehyde, 5 organic acids, 2 alkaloids, 5 terpenes, 1 ketone, 7 phenylpropanoids, 2 coumarins, 1 nucleoside, 26 flavonoids, 1 anthraquinone, and 1 lignan. Conclusion The application of UPLC-QE-MS technology, combined with relevant databases and literature, enables the analysis of the chemical components of the peel of Wogam, providing a basis for the industrial development of Wogam peel.

Agricultural product safety form the foundation of constructing food supply systems. Smart hydrogels exhibit promising application prospects in agricultural safety analysis due to their stimuli responsiveness, mechanical stability, biocompatibility, and adjustable pore size. This review focused on the classification, preparation methods, responsive mechanisms and applications of smart hydrogels in agricultural product safety. Based on synthesis methods, they could be divided into physically cross-linked and chemically cross-linked hydrogels, while stimulus-responsive types included temperature-responsive, pH-responsive, biomolecule-responsive, electric field-responsive and magnetic field-responsive hydrogels. This study summarized their applications in contaminants adsorption/separation, foodborne pathogen detection, mycotoxin detection, pesticide/veterinary drug residue analysis, illegal additive identification, and heavy metal detection for agricultural product assurance. Development prospects of smart hydrogels are further discussed to provide references for their expanded utilization in agricultural product safety.

Objective To develop a sensitive and stable dual signal output indicator label and realize real-time monitoring of the freshness of Litopenaeus vannamei. Methods Based on polyvinyl alcohol (PVA)/agar composite matrix combining anthocyanins (ACNs), silver coated gold nanoparticles (Au@AgNPs) and the metal organic framework material UiO-66, the dual signal output indicator labels were prepared by casting method. Next, the stabilizing effect of UiO-66 on the labels was investigated by storage stability, ultraviolet stability and anti-migration experiments. Ammonia, dimethylamine and trimethylamine were used as characteristic volatile markers to evaluate the gas sensitive response performance of the labels. Ultimately, the label was applied to real-time monitoring of the freshness of Litopenaeus vannamei. Results Compared to labels without UiO-66, the addition of UiO-66 effectively immobilized the anthocyanins and improved the UV stability and storage stability of the label. In addition, the label showed excellent responsiveness to ammonia and amine gases. In the application of freshness monitoring of Litopenaeus vannamei, the color of the indicator label gradually changed from purplish-red to bluish-green with the change of freshness of Litopenaeus vannamei. The partial least squares regression (PLSR) model based on the surface-enhanced Raman scattering (SERS) signals showed excellent prediction performance for the total volatile basic nitrogen (TVB-N) values, with a correction set coefficient of calibrated coefficient of determination (R²_C) of 0.951, cross-validated coefficient of determination (R²_CV) of 0.899, predicted coefficient of determination (R²_P) of 0.966, and residual prediction deviation (RPD) of 4.765. Conclusion A colorimetric-SERS dual-signal output indicator label is developed in this study. The label enable simultaneous visual identification of the freshness of Litopenaeus vannamei and high-sensitivity prediction of TVB-N values, providing a reference for the design of novel intelligent food packaging systems.

Objective To detect and analyze the content of mineral elements in wines of different varieties and years from the Helan Mountain East Slope region, and construct a model for identifying wine varieties and years based on mineral elements using multivariate statistical analysis methods. Methods Grapes of 5 varieties, namely, Zinfandel, Merlot, Malbec, Cabernet Sauvignon and Marselan, were collected from a winery in Qingtongxia, Ningxia, and were processed into wines using the same method. Wines of the Cabernet Sauvignon variety from 6 years (2018—2023) were collected from a winery in Yongning, Ningxia. The content of 54 kinds of mineral elements including B, Bi, Be, etc. in the wines was determined by inductively coupled plasma mass spectrometry. A model for identifying wine varieties and years was constructed based on the differences in mineral element content among different varieties and years of wines. Results A total of 53 mineral elements were detected in wines of different varieties, and 47 kinds of mineral elements including As and B showed extremely significant differences among varieties (P<0.01). All 54 kinds of mineral elements were detected in wines of different years, and all showed extremely significant differences among years (P<0.01). The correct discrimination rate of the model for identifying wine varieties and years based on Fisher discriminant analysis was 100%. The 9 kinds of mineral elements, namely, As, Cs, Dy, Mo, Na, Sb, U, Yb and Fe, were identified as the differential elements for different varieties of wines, and 11 kinds of mineral elements, namely, Cu, Li, Na, Sb, Tl, U, V, Y, Yb, Ag and Pt, were identified as the differential elements for wines of the same variety from different years. The correct discrimination of wines from the same origin but of different varieties and years was achieved based on mineral elements. Conclusion Mineral elements show significant differences among wines of different varieties and years, and can be used for the identification of wine varieties and years from the same region.

Objective To optimize the subcritical water extraction process of Pollen pini polysaccharides based on genetic algorithm-neural network (GA-NN) algorithm and further explore its anti-fatigue activity. Methods Using broken shell Pollen pini as raw material, a response surface was designed through Box-Behnken test on a single factor basis, and a network neural model was constructed and optimized using GA-NN algorithm. Under the optimal process conditions, the anti-fatigue effect of polysaccharides was evaluated through mouse weight-bearing swimming test. Results The relative error and coefficient of determination (R²) of the constructed neural network model were 0.03267 and 0.98476, respectively. The genetic algorithm was iterated 60 times for subcritical water extraction of polysaccharides, and the optimal parameters were obtained as follows: Temperature 148 ℃, time 28 min, liquid to material ratio 40:1 (mL/g), pressure 5 MPa, and polysaccharide yield of 23.7893 mg/g. After verification, there was no significant difference between the actual value and the predicted value, indicating good accuracy of the model. The study on anti fatigue activity showed that compared with the blank group, the high-dose group of mice had a certain degree of increase in body weight, while there was no significant difference in other groups (P>0.05). Compared with the blank group, the swimming time of mice in the polysaccharide group was prolonged, the levels of blood lactate and urea nitrogen were reduced, and the reserves of muscle glycogen and liver glycogen were significantly increased (P<0.05). Conclusion GA-NN can effectively optimize the subcritical water extraction process of Pollen pini polysaccharide, and the polysaccharide has a certain anti fatigue effect.