Latest ArticlesObjective 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.
Food safety is crucial for national economic development and public health. With the development of science and technology, traditional detection methods is difficult to meet the supervision requirements of food safety in complex scenarios. In recent years, artificial intelligence (AI), with its high efficiency, high accuracy, powerful data processing capabilities, and precise identification and predictive analysis functions, has gradually been applied to research fields such as food flavor analysis, food safety risk assessment and early warning, and authenticity identification. The application of AI technology has improved the timeliness and reliability of food quality and safety testing, and has built a prevention and control system covering the entire industry for regulatory departments through intelligent decision-making assistance systems, becoming the core technical support for ensuring “safety on the tip of the tongue”. This paper mainly introduced the main algorithms of machine learning and deep learning algorithms, and reviewed the research progress of AI algorithms in food quality and safety. Additionally, it looks ahead to the existing problems and future research trends of the application of AI algorithms in food quality and safety. The aim is to offer references for further promoting the research and practice of AI technology in the field of food quality and safety, and to provide research ideas for the field of food quality and safety detection.
Objective To analyze the key factors affecting constant weight in the direct drying method and to optimize the experimental conditions for vacuum drying, distillation, and Karl Fischer methods as specified in the GB 5009.3—2016 National food safety standard-Determination of moisture in foods. Methods The determination of moisture content in samples was conducted according to GB 5009.3—2016. The study altered experimental conditions to explore key factors affecting constant weight in the direct drying method, optimized conditions for vacuum drying by adjusting vacuum pressure, and compared the effects of different reagents (xylene, Karl Fischer reagent) on detection results. Results In the direct drying method, sample temperature, cooling time in the desiccator and the degree of sample pulverization were identified as key factors affecting constant weight. For vacuum drying method, increasing the vacuum to -0.1 MPa and adding an effective desiccant to the drying box could rapidly evaporate moisture from the sample, improving detection efficiency. In the distillation method, the preparation and purification of analytical-grade toluene or xylene could be omitted. The Karl Fischer method could use a low-toxicity, pyridine-free Karl Fischer reagent. Conclusion The 4 detection methods in this standard are optimized separately to solve problems such as difficulty in achieving constant weight after repeated drying and the use of toxic and harmful reagents. The rationalization suggestions provide in this study have increased the operability of the standard and improved the testing efficiency of the laboratory.
Objective To prepare edible gelatin-corn starch bio-based composite film loaded with lactive Lactiplantibacillus plantarum CXG9, and endow the film with antibacterial activity and excellent film properties. Methods Using gelatin and corn starch mixed film as substrate, the bacterial mud obtained by Lactiplantibacillus plantarum CXG9 centrifugation was mixed into gelatin-corn starch mixture, and the living bacteria edible composite film was prepared by solution casting method. By measuring the characterization of the film and its antibacterial activity in vitro, the effects of Lactiplantibacillus plantarum CXG9 on the properties of gelatin-corn starch film were studied. Results The elongation at break of the gelatin-corn starch composite film loaded with Lactiplantibacillus plantarum CXG9 increased by 35.51%, the moisture content decreased by 2.55%, and the water vapor permeability also decreased by 11.2%. This indicated that the ultraviolet barrier ability, water vapor permeability, elongation at break, and thermal stability of the film loaded with Lactiplantibacillus plantarum CXG9 had all been improved. On the other hand, the addition of live bacteria gave the film antibacterial properties, and it had different degrees of inhibition on Listeria monocytogenes, Shigella, Escherichia coli, Staphylococcus aureus, Salmonella typhimurium and Pseudomonas aeruginosa. Conclusion In this study, gelatin-CXG9-corn starch antibacterial film loaded with Lactiplantibacillus plantarum CXG9 is successfully prepared by using gelatin-corn starch as substrate, which reduces the burden of traditional packaging materials on the environment and opens up a new way for the development of food packaging field.
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 establish a rapid detection method of viable Pediococcus pentosaceus in rose jam based on the combination of propidium monoazide (PMA) and quantitative real-time polymerase chain reaction (qPCR). Methods Primers specific for Pediococcus pentosaceus were designed according to the species-specific murI gene. The optimal PMA treatment conditions were determined by optimizing the PMA concentration, dark incubation time, and exposure time. Different ratios of Pediococcus pentosaceus dead/live bacterial mixtures were validated by the PMA-qPCR method to assess the sensitivity and limit of detection of the technique. Results The designed primers exhibited high specificity, and the optimal PMA treatment conditions were determined as 80 µg/mL PMA, 15 min of dark incubation, and 25 min of exposure. Under this condition, a standard curve with correlation coefficient (r2) of 0.9983 was constructed, and the lowest limit of detection was determined to be 3.98×103 CFU/g. Conclusion The PMA-qPCR method established in this study enables the rapid and accurate quantification of viable Pediococcus pentosaceus in rose jam with high sensitivity, providing technical support for the quantitative detection of microorganisms in complex food matrices.
Objective To investigate the effects of different degree of low substitution degree on the physicochemical properties of potato starch, and apply it to the hard capsule shell to observe the effect of potato acetate starch on its properties. Methods Potato starch was used as raw material and acetic anhydride as esterifying agent to prepare esterification modified starch with different low degree of substitution (0.0143-0.0570). The physical and chemical properties and structural changes of different starch with low substitution degree were investigated, and it was used in the preparation of hard capsule shells. Results Both potato starches with different low substitution degrees and the original starch were shear-thinning type pseudoplastic fluids. The energy storage modulus and loss modulus of modified starch showed an increasing trend, and the storage modulus was larger than that of original starch. Compared with the original starch, the transparency, gel strength and water holding capacity of modified starch were improved. The swelling degree and solubility increased. The esterification reaction of acetic anhydride with potato starch occurred mainly on the surface of starch particles, and did not change the crystallization type of potato starch. The modified starch paste of potato was used to prepare the hard capsule shell and all the indexes met the requirements of Pharmacopoeia of the People’s Republic of China (2020 edition). Conclusion The low substitution degree of acetate starch can improve the performance and application range of natural starch, which is in line with the national food safety standards. The preparation of plant hard capsules instead of gelatin capsules can make up for the shortcomings of natural starch in the preparation process, and it is in line with the standards stipulated in Chinese pharmacopoeia.
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 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.