As the world's largest producer and consumer of meat products, its consumption structure, industry development and food safety issues significantly shape both its domestic consumer market and global trade patterns. The increase in per capita disposable income of Chinese residents has promoted the diversified development of the consumption structure of meat and meat products, the progress of food technology and industry system has promoted the development of the industry towards product diversification, technological perfection and process systematization, and gradually formed a standard system pattern with mandatory standard system as the core and recommended standard system as the main body. Although China's meat and meat products industry has developed for many years with a relatively complete standard system and industrial pattern, there are still problems such as insufficient coordination of standards and lagging revision and review cycles. The diversification of consumption and industrial structure has led to increasingly prominent food safety issues. This review systematically summarized the urban and rural consumption characteristics of meat and meat products in China, as well as their standard system and industry development. It comprehensively analyzed the risks of the entire chain of meat and meat products from breeding to processing, and proposed suggestions for the problems existing in their development process to promote the healthy and stable development of China's meat and meat products industry.

Objective To investigate the differences in mineral element content between sole fish and basa fish and establish an authenticity identification method. Methods Inductively coupled plasma mass spectrometry were employed to determine 25 kinds of mineral elements in 29 sole fish samples and 24 basa fish samples. Principal component analysis were performed using SPSS 25.0 software on the measurement results, and comparative analysis were conducted on mineral element contents among 3 kinds of different genera of sole fish. Results The total mineral element content in sole fish were significantly higher than that in basa fish. Na, K and Ca were identified as the primary mineral elements in both species, with Sr, As, Mn, Fe and Zn serving as secondary elements. Notably, Sr, As, Mn and Fe were detected exclusively in sole fish but absent in basa fish. Significant differences were observed in 9 kinds of elements: Mg, Ti, Zn, As, K, Ca, Na, Mn, and Fe. Principal components of sole fish within the same genus exhibited relative clustering, with marked differences in 7 kinds of elements: V, Mn, B, Ba, Fe, As and Sr. Conclusion Mineral element analysis can effectively distinguish sole fish from basa fish for authenticity verification.

Objective To explore the effects of ultrasonic synergistic enzymatic hydrolysis on the antioxidant activity and structure of donkey milk casein, optimize the process parameters of composite treatment, and analyze the promotion mechanism of ultrasonic pretreatment on the enzymatic hydrolysis process. Methods Using donkey milk casein as raw material, the ultrasonic parameters (200 W, 20 min, 6 s/6 s intermittency ratio) were optimized by single factor experiment, the neutral protease and trypsin (the mass ratio was 2:1) were screened, and the enzymatic hydrolysis conditions were optimized by response surface method (enzyme addition amount 4.86%, 55.28 °C, pH 7.76). The changes of protein molecular weight, secondary structure and functional groups were analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and infrared spectroscopy. The antioxidant indexes such as 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging rate were determined. Results Ultrasonic synergistic enzymatic hydrolysis resulted in antioxidant ability of 69.77% and a 65.3% increase in Fe³⁺ reducing capacity, which was significantly better than that of the single treatment. The structure showed that the α-helix decreased to 26.70%, the random coil increased to 28.35%, the aromatic amino acids were exposed, the sulfhydryl groups were oxidized to disulfide bonds, and the molecular weight was reduced. The predicted value of the response surface model was in good agreement with the measured value (R²=0.9937). Conclusion The results of ultrasonic pretreatment significantly improves the antioxidant activity by destroying the structure of protein micelles and releasing antioxidant short peptides in synergy with enzymes, which provides a reference process parameter for the production of high value-added donkey milk antioxidant products, which is helpful to promote the development of donkey milk industry and improve the economic value of donkey milk.

Objective To assess the risks of pesticide residues of animal-derived foods in commercial market. Methods The 146 kinds of pesticides were determined in 460 batches of animal foods by gas chromatography-tandem mass spectrometry. The risk of pesticide residues detected in animal foods was evaluated by food safety index (IFS) method and dietary risk assessment model. Results The overall detection rate of the sample was 48.9%, and a total of 24 kinds of pesticides were detected, primarily insecticides, with low and moderate toxicity being the main characteristic. Among the detected samples, the number of detected pesticides was the highest in aquatic products, followed by eggs, livestock meat and poultry meat. Among the detected pesticides, the largest number of pesticides were detected in aquatic products, followed by livestock meat, poultry meat and eggs. The pesticides in aquatic products were mostly hexaflumuron, pendimethalin, DDT, dimethoate, trifluralin, thifluzamide and carbaryl. While the livestock meat was mainly diphenylamine, ethoprophos and boscalid, the poultry was mainly boscalid, and the eggs were mainly fipronil. The results of IFS showed that the average safety index ($\overline{\text{IFS}}$) of all pesticides was 0.000001-0.010021, which was far less than 1. The overall safety status of all pesticides in animal foods was acceptable. The results of dietary risk assessment indicated that acceptable daily intake (%ADI) of each detected pesticide in the 4 types of animal-derived foods were far less than 100%, and the hazard quotient (HQ) and hazard index (HI) were far less than 1. The risk level of these pesticide residues of animal foods was within the acceptable range. Conclusion There are pesticide residues in animal-derived foods. Although the overall risk of pesticide residues detected in animal-derived foods is relatively low and within an acceptable range, however, samples and pesticides with high detection rates should be the focus of supervision to ensure the safety of animal-derived foods in the future.

Objective To explore the mineral element differences in different visceral by-products of Simmental beef cattle in Ningxia. Methods Using post-slaughter by-products from Ningxia Simmental cattle (beef heart, beef liver, beef tripe, beef intestines) as the research subject, the content differences of 42 kinds of mineral elements in the 4 kinds of by-products were detected and analyzed. And verified through discriminant analysis. Results The results indicated that there were significant differences in the content of 38 kinds of and 41 kinds of mineral elements respectively in the 4 kinds of beef cattle by-products from Guyuan and Wuzhong regions (P>0.05). The content of Pb, Cd, Hg, As, Cr in all beef cattle by-products is below the limit standards. Beef tripe has a strong adsorption and accumulation effect on heavy metals such as Ni and Cr, rare earth elements Eu, Gd, Nd and Sm, as well as other elements included Nb, Sb and Sn; beef liver had a strong absorption and enrichment effect on heavy metals like Cd, trace elements Cu and Mo. Based on mineral elements, effective differentiation of various by-products and samples from different origins could be achieved. Selected Cs, Na, Li, Cd, Tl, Rb, Cr, U, Pt, Ta, Co, Sc, Mo, Ni, Zn, Ir, Sn and Fe as the key characteristic elements for distinguishing between cow stomach, cow liver, cow heart, and cow intestine. Eleven key elements had been identified to distinguish the origin of beef by-products from Guyuan and Wuzhong, included Cs, Cr, Rb, As, Sn, Nb, Ni, Li, Sb, Ti and Hg. Conclusion Beef by-products have their own elemental characteristics, and different by-products and samples from different origins can be effectively distinguished by the content of mineral elements. The research findings will help establish a quality database for beef by-products, providing data support for the development of new products by enterprises.

Objective To optimize the frying formulation and process of rice bran-enriched chicken cutlets. Methods Taking sensory evaluation as the assessment criteria, single-factor experiments were conducted to examine the effects of rice bran addition amount, wheat flour and corn starch ratio, frying temperature and frying time on the quality of fried chicken cutlets. Orthogonal experiments were employed to optimize the addition amounts and process parameters. Data analysis was performed using IBM SPSS Statistics 20, with P<0.05 indicating statistically significant differences. Origin was used for graphical visualization. Results The order of influence of various factors on the sensory quality of fried chicken chops was: Frying temperature>frying time>wheat flour and corn starch ratio>rice bran addition. The frying conditions were determined by comprehensive consideration: Rice bran addition 0.8% (m:m), wheat flour and corn starch ratio 1:1 (m:m), frying temperature 180 ℃, frying time 2 min. The sensory score of fried chicken chops under this condition was 90.1 points. The fried chicken chops had uniform golden color, rich aroma, moderate hardness, good brittleness and sensory quality. Conclusion It is feasible to add rice bran to the traditional coating formula, which can provide a theoretical basis for mass production industrialization.

Objective To explore the application areas of rapid detection technology for core quality indicators in cheese and its products using near-infrared spectroscopy (NIRS), and validating the feasibility of NIRS for rapid testing of cheese quality parameters. Methods Four types of common processed cheese products (cheese sticks, cheese slices, cream cheese, Mozzarella) were selected for experimentation and divided into modeling and validation sets; modeling experiments were conducted using samples from the modeling set on a single-brand instrument; synchronous national standard detection and multi-instrument NIRS detection comparative analysis were performed using instruments from 4 different manufacturers on the validation sets. Results For modeling, multidimensional prediction models for core indicators (protein, fat, moisture, pH) were successfully constructed by comparing the modeling mechanisms of algorithms like partial least squares regression (PLSR), with the coefficient of determination exceeding 0.85. For validation, the average deviations between the NIRS detection results (protein, fat, moisture) obtained using 4 kinds of NIRS spectrometers on different cheese products and those determined by national standard methods met equivalence requirements except for the protein deviation (>10%) of Mozzarella on instrument No.1; precision also met the requirements of national standard methods. Conclusion The application of NIRS spectroscopy equipment for rapid detection of core quality indicators in cheese and its products is feasible; NIRS spectroscopy technology can serve as an effective supplement to traditional chemical detection methods for rapid analysis of cheese composition, offering greater potential for high-efficiency, low-cost, and environmentally friendly testing.

Objective To establish a fingerprint spectrum for the volatile compounds of A brand ready-to-eat bird's nest by solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS), and conduct differential analysis on different brands and types of ready-to-eat bird's nest products. Methods Using commercially available ready-to-eat bird's nest as the research object, SPME-GC-MS was used to analyze the volatile substances in 37 batches of A brand ready-to-eat bird's nest samples with different storage periods. The volatile substances were analyzed through the database of NIST 20 and the method of peak area normalization. The “TCM chromatographic fingerprint similarity evaluation system” was used to establish the volatile substances fingerprint spectrum of A brand ready-to-eat bird's nest. Results Under the service of NIST 20 database, 26 kinds of characteristic volatile components were identified in brand A's ready-to-eat bird's nest, mainly including unsaturated compounds such as 5-hydroxymethylfurfural, nonanol, lauryl alcohol, tetrahydro lavender alcohol, benzaldehyde, and so on. A fingerprint spectrum of the volatile substances in this ready-to-eat bird's nest product was established. The evaluation criteria were based on a total of 26 matching peaks, the similarity was greater than or equal to 65.8%, which could be well applied to evaluate the quality of different commercially available ready-to-eat bird's nests. Conclusion By analyzing the composition of volatile substances in ready-to-eat bird's nest and establishing a fingerprint and similarity evaluation method of volatile components for ready-to-eat bird's nest, it is possible to effectively distinguish different quality levels of ready-to-eat bird's nest, providing a scientific basis for quality control and authenticity identification of ready-to-eat bird's nest.

Objective To establish a method for the determination of 5 kinds of drugs (atropine, procaine, scopolamine, anisodamine and lidocaine) in lard and pork by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Methods The pretreatment conditions and instrument parameters were optimized. HLB Pro solid-phase extraction cartridges were used for purification, with 1 mL of 30% acetonitrile and 1 mL of pure acetonitrile for elution. The residues of the 5 kinds of veterinary drugs in lard and pork were determined under the following conditions: 5 kV capillary voltage, 540 °C desolvation gas temperature at 13 L/min, 2 L/min nebulizer gas flow, 1.2 L/min cone gas flow, and multiple reaction monitoring mode. Results The calibration curves of the 5 kinds of drugs showed good linearity in the mass concentration range of 0.1-10.0 ng/mL, with correlation coefficient (r²)>0.9950. The limits of quantitation ranged from 0.013 to 0.142 µg/kg. Recoveries were between 84.72% and 106.24%, and precision (n=6) ranged from 0.45% to 7.32%. No target drug residues were detected in the tested pork and lard samples. Conclusion This study establishes a detection method based on a domestically produced LC-MS/MS system and HLB Pro solid-phase extraction columns, providing a cost-effective and reliable solution for the efficient screening of the 5 kinds of veterinary drug residues in pork and lard.

Mycotoxins are secondary metabolites produced by fungi, which accumulate in the food chain and enter the human body, endangering human health. In recent years, nanozymes with controllable morphology and enzyme-mimicking activity have shown significant advantages in the detection of mycotoxins. This paper mainly summarized the application research of nanozyme biosensors in the detection of mycotoxins, divided nanozymes into metal oxide-based, noble metal-based and carbon-based nanozymes according to the material components, analyzed the dynamic regulation mechanism of nanostructure parameters (including size, morphology, surface modification) on enzyme-mimicking activity, and then explored the technical advantages of nanozymes in colorimetric, fluorescence, electrochemical and Raman detection, revealing its application potential in the rapid detection of mycotoxins. In addition, this paper prospected the application of biosensors constructed by nanozymes in the detection of mycotoxins, aiming to provide theoretical support and technical foresight for the application of nanozymes in the field of food safety detection, and it was expected to provide guidance for the industrial development of the detection field.

Food safety issues induced by pesticide residues pose multiple threats to public health, ecological balance and international trade. In this context, the development of novel analytical technologies featuring rapid response, high sensitivity and on-site applicability has become an urgent requirement in food safety detection. Electrochemical biosensors have demonstrated significant potential in pesticide residue detection due to their unique analytical advantages. Particularly, high performance sensing interfaces constructed with nanomaterials show remarkable improvements in sensor sensitivity, selectivity and stability through their high specific surface area, excellent catalytic activity, and superior electrical conductivity. This paper reviewed the working principle of electrochemical biosensors, focused on discussing the application of nanomaterials in constructing different types of electrochemical biosensors for pesticide residue detection, and looked forward to the future technological development, providing theoretical support and research directions for building a precise and efficient pesticide residue detection system.

Objective To develop a rapid and sensitive detection technology for pathogenic microorganisms in food packaging based on the clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated protein 13a (Cas13a) system. Methods The method leveraged the specific recognition and signal amplification characteristics of the CRISPR-Cas13a technology. Multiple guide RNAs were designed to target different sites on pathogenic RNA, enabling a single RNA molecule to activate multiple Cas13a enzymes simultaneously. This cascade triggered trans-cleavage of RNA reporter molecules in the reaction mixture, generating a detectable fluorescent signal. The tandem design synergistically enhanced signal amplification efficiency, thereby improving detection sensitivity. Results The limits of detection of this method for pathogenic and RNA were 800 copies/mL and 18.7 pmol/L, respectively, and the detection could be completed in a short time, accurately distinguishing different pathogens. Testing food packaging samples contaminated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pseudvirus showed recovery rates ranging from 89.71% to 102.56%. Conclusion This study presents a rapid, cost-effective and easy-to-operate method for detecting pathogenic microbial contamination on food packaging surfaces, indicating high accuracy, offering potential application value for monitoring microbial risks in foodborne transmission pathways.

Objective To construct a novel fluorescent aptamer sensor based on MXene nanomaterials by combining X-type DNA with aptamers for the simultaneous detection of Pb²⁺ and Cd²⁺ in food. Methods X-type DNA structures were prepared by complementary base pairing, and in the presence of Pb²⁺ and Cd²⁺, the aptamer within the X-type DNA structure specifically bound to the target ions and triggers desorption from the MXene surface, thereby restoring the fluorescent signal. Results Under the optimal experimental conditions, the fluorescence signal intensity was linearly correlated with Pb²⁺ and Cd²⁺ in the range of 0.5-500.0 nmol/L, with the limits of detection were 0.33 nmol/L and 0.28 nmol/L, respectively, and the results showed that the sensor had good working performance. Conclusion The fluorescent biosensor prepared in this study has been successfully applied to the spiked analysis of tap water and cornmeal with good recoveries, indicating that it can be used as an effective tool for the detection of Pb²⁺ and Cd²⁺ in food.

Objective To construct a carbon nanotube-poly(neutral red) modified electrode for the competitive electrochemical rapid detection of putrescine in Procambarus clarkii samples. Methods Putrescine was selected as a freshness indicator for Procambarus clarkii. A carbon nanotube-poly(neutral red) modified electrode was designed for putrescine detection. The relationship between the electrochemical behavior of the electrode and the concentration of putrescine was explored, and its application in electrochemical sensing of putrescine was investigated. After optimizing factors such as scan rate and electrolyte pH, the putrescine content in Procambarus clarkii was determined. Recovery experiments were conducted, and the results were compared with high performance liquid chromatography. Results The carbon nanotube-poly(neutral red) modified electrode exhibited a significant electrochemical inhibition effect towards putrescine, with a notable inverse relationship between the concentration of putrescine and the peak current of the electrode. The linear range was described by the equation ΔI=3.8ln[c_(PUT)]+8.3, with a correlation coefficient of r=0.99. When applied to the detection of putrescine in crayfish samples, the results obtained by this method were highly consistent with those obtained by the high performance liquid chromatography. Conclusion The method can be employed for the detection of putrescine concentration in Procambarus clarkii and serves as a biosensor for putrescine, a freshness indicator of Procambarus clarkii.

Objective To establish a rapid colorimetric method for the detection of histamine in fish samples based on the oxidase activity of Ag₃PO₄ nanozyme. Methods Ag₃PO₄ nanoparticles were prepared by the hydrothermal method. Utilizing their oxidase catalytic activity, with CH₃COONa as the buffer system and 3,3',5,5'-tetramethylbenzidine as the oxidation substrate, a rapid colorimetric detection method for histamine in fish was established. Results The detection time of this method was about 100 seconds. The limit of detection was 0.58 mg/L, indicating high detection sensitivity. In the detection of multiple competitive targets, this method showed good specificity for histamine molecules. In the spiked experiments on actual samples, the spiked recovery rate of this method ranged from 104.24% to 108.30%, and the relative standard deviations were from 1.81% to 3.44%, which had good detection accuracy. Conclusion This method demonstrates the advantages of being intuitive, rapid, highly sensitive and having good specificity. It can adapt to the complex daily detection environment and provides a new idea for the detection of histamine in fish meat.

In the face of global population growth and agricultural production pressure, as well as the serious challenges of agricultural product quality and safety issues, the traditional methods of agricultural product integrity monitoring and risk prediction have become insufficient. The rapid development of machine learning technology provides new solution ideas for agricultural product integrity monitoring and risk prediction. This paper systematically summarized the applications of machine learning technology in agricultural product safety risk monitoring (including physical, chemical and biological risks), agricultural product authenticity and traceability assurance, and agricultural product risk assessment prediction based on historical data. Machine learning technology undoubtedly improves the efficiency of agricultural product integrity monitoring effectively, realizes early detection and prevention of risks, and provides new solution for constructing a safer and more reliable food supply chain provides new solutions. Although these applications show great promise, there are still challenges to artificial intelligence in the field of agricultural produce integrity monitoring and risk prediction. Based on summarizing the literature, this paper further explored the prospects and directions of this trend, and presented the importance of machine learning model interpretability and trust issues, as well as problems in data acquisition and use, to improve the application of machine learning in agricultural product integrity monitoring and risk prediction.

Against the backdrop of the continuous expansion of the global dried fruit market, China, as a major producing country, faces food quality control and international trade barriers caused by imperfect standard systems. This study was based on a systematic review of 11 international and domestic standards for dried fruit products, compared and analyzed the differences in key quality indicators such as sensory evaluation, moisture content, total acidity, total sugar, ash content and impurities. The study found that although China's current standards were stricter than international standards in terms of total acidity, total sugar, and impurity limits, there were prominent issues such as a chaotic grading system for sensory indicators, lack of consistency in moisture threshold values (e.g., the domestic standard moisture limit for raisins was 15 g/100 g to 20 g/100 g), and significant differences in total sugar limits (e.g., different standards for dried dates require total sugar levels ranging from 60% to 75%). Additionally, some indicators (such as the moisture limit for dried peaches at 30 g/100 g) were lower than international standards (ISO 7703:1995 limit less than or equal to 20%). This study recommends: Adopted a dual-track optimization approach of “integrating domestic standard systems+breaking through international standard strategies”, accelerated the formulation and implementation of national standards for dried fruit food safety to strengthen supervision, systematically revise industry standards to eliminate indicator conflicts, and take the lead in developing international standards for specialty products, thereby comprehensively enhancing the quality competitiveness of China's dried fruit industry and its voice in international standard setting.

Objective To analyze the food safety issues and risk existing in the food safety supervision and sampling inspection data of Jiangsu Province from 2021 to 2023. Methods By summarizing the sampling data of food safety supervision in Jiangsu Province from 2021 to 2023, a comprehensive analysis was carried out from multiple dimensions including unqualified rates, food categories and unqualified items. Results In the past 3 years from 2021 to 2023, a total of 129665 food were sampled in Jiangsu Province, and the overall unqualified rate was 1.87%. From the unqualified sampling batches perspective, edible agricultural products recorded the highest number of sampled batches (917 batches) and the highest unqualified rate (39%), followed by catering foods with 446 sampled batches and a 19% non-compliance rate. The main problems included excessive residues of pesticides and veterinary drugs, substandard quality indicators and microbial pollution, with a total of 71.8% of unqualified samples. Excessive pesticide residues were predominantly identified in ginger (73 batches of thiacloprid) and Chinese chives (54 batches of procymidone). Excessive veterinary drug residues were primarily characterized by enrofloxacin contamination, mainly detected in bream, crucian carp, swamp eel, giant river prawns and other aquatic products. The main issue of non-compliance with substandard quality indicators was principally manifested through elevated peroxide values and acid values in roasted nuts and nut products, as well as pastries. Microbial contamination was concentrated in catering foods (195 batches of coliform bacteria) and pastries (89 batches of total bacterial count). Conclusion Food safety risks in Jiangsu Province show a trend of category concentration. Attention should be paid to edible agricultural products, catering foods, pastries, fried foods and nut products, as well as agricultural and veterinary drug residues, substandard quality indicators and microbial contamination, etc. It is suggested to improve regulatory measures from the aspects of source control, food hygiene management, sampling program optimization and social co-governance to reduce food safety risks.

Objective To investigate the content of 16 kinds of rare earth elements in commercial vegetables and evaluate the health risks caused by the intake of rare earth elements in vegetables for users in Gansu Province. Methods Samples from 6 categories were collected from 13 areas in Gansu Province, and the content of the 16 kinds of rare earth elements were measured by inductively coupled plasma mass spectrometry. According to the health risk analysis method recommended by United States Environmental Protection Agency (USEPA), the allowable daily intake (ADI) was used to assess the health risk of rare earth elements in commercial vegetables. Results The earth elements of vegetables sold in Gansu were mainly Sc, Y, Ce, La, Nd, Pr, with detection rate exceeds 50%, the total content of rare earth elements in the 6 types of vegetables was 0.1764 mg/kg, ranked from high to low as follows: Melon and fruit vegetables>leafy vegetables>stem vegetables>solanaceous fruit vegetables>root vegetables>bean vegetables. There were no significant differences in the content of rare earth elements among different vegetable categories (P>0.05), but significant differences were observed among vegetables from different areas (P<0.05). The health risks posed by the 16 kinds of rare earth elements varied among different population groups, with adult males and females exhibiting higher risks than children. The daily intake of rare earth elements through vegetable consumption was 0.0025 mg/(kg d), which was below the reference value of 0.07 mg/(kg d). Conclusion The content of rare earth elements in commercial vegetables in Gansu Province is low. The intake of rare earth elements through vegetables by residents will not pose a risk to human health.

Objective To investigate the distribution of 26 kinds of metal elements (Pb, Cd, Hg, As, Cr, Al, Mn, Cu, Ba, V, Se, Sb, Ni, Sn, Li, B, Zn, K, Na, Ca, Mg, Fe, Sr, Mo, Co, Rb) and assess the dietary risk with cereals in Handan City. Methods A total of 51 cereal samples (wheat and maize) were analyzed for 26 kinds of metal elements using inductively coupled plasma mass spectrometry (ICP-MS). Statistical analysis was performed on the detection results, and nutritional and exposure risk assessments were conducted for macro- and trace elements using the individual pollution index, target hazard quotient, carcinogenic risk, and estimated daily intake. Results The method demonstrated good linearity, high accuracy, and sensitivity. Among the 26 kinds of metal elements, 24 kinds of metal elements were detected in the cereal samples, except for Hg and Li. Principal component analysis and correlation analysis revealed interspecies differences between wheat and maize, as well as distinct correlations among different elements. The contamination levels of 5 kinds of heavy metals (Pb, Cd, Hg, As, Cr) were within safe limits. The target hazard index of 19 kinds of metal elements and the carcinogenic risk index for Pb were significantly below threshold levels, indicating no health risks, but the carcinogenic risk assessment for As suggested potential health risks. Nutritional assessment showed that the cereals were rich in K and Mg, but low in Na. However, Cr exposure reached nearly 300% of the adequate daily intake, indicating a significant health concern. Conclusion The established method is effective for multi-element analysis in cereals. This research findings provide updated dietary intake assessment of multi-elements of Handan adult consumers. The dietary assessment indicates that intake of cereals in Handan City poses no significant health risks, but particular attention should be paid to Cr and As contamination.

Objective To explore the application of the combination of real-time fluorescence quantitative polymerase chain reaction (qPCR) and droplet digital polymerase chain reaction (ddPCR) in the quantitative detection of meat adulteration. Methods This study employed qPCR and ddPCR technologies to develop a detection system with specific primers and probes for beef, lamb and pork samples, aiming to assess meat adulteration in the Beijing market. Results The experimental results revealed that the sample “Chang 5” contained adulteration of lamb and pork at a ratio of 17:10. qPCR demonstrated high sensitivity and specificity in qualitative detection, while ddPCR enabled absolute quantification of adulteration proportions. The combination of these 2 methods significantly improved detection accuracy. Conclusion The established qPCR-ddPCR combined method exhibits high sensitivity and specificity, making it suitable for rapid and precise detection of meat adulteration. This approach provides reliable technical support for food safety regulation.

Objective To analyze the characteristics of foodborne disease outbreaks in schools in Zibo City from 2019 to 2023. Methods The school food-borne disease outbreaks reported in Zibo City from 2019 to 2023 were collected through the national foodborne disease outbreak surveillance network for descriptive analysis. Results From 2019 to 2023 a total of 23 school foodborne disease outbreaks were reported, with a total of 337 cases, 35 hospitalized, and no death. Summer and autumn were the most common seasons. The incidents with clear pathogenic factors accounted for 34.78% (8/23), and the incidents caused by microorganisms and their toxins accounted for 75.00% (6/8). Staphylococcus aureus and its enterotoxin were the main pathogenic factors, accounting for 33.33% (2/6) of the outbreaks of microorganisms and their toxins. The most common causes of food were mixed food and other foods, accounting for 30.43% (7/23) and 26.09% (6/23), followed by food products, meat and meat products, accounting for 17.39% (4/23) and 13.04% (3/23). The main source of food was the school canteen (73.91%, 17/23). The main triggering factors were multiple factors, followed by the misuse of poisonous plants. Conclusions Microorganisms and their toxins are the main factors causing foodborne disease outbreaks in schools. Summer and autumn are the high incidence seasons. It is necessary to strengthen the food safety risk control of school canteens and strengthen the collaboration of multi-departments to reduce the occurrence of foodborne disease outbreaks in schools.

Objective To investigate on the pesticide residue situation of Vitis vinifera L. in Shuanghe City, the Fifth Division, to Vitis vinifera L. the quality and safety status of Vitis vinifera L.. Methods From 2023 to 2024, a total of 715 batches of Vitis vinifera L. in Shuanghe City, Fifth Division, were tested for 41 kinds of pesticide residues. Results The random inspection results showed that 20 kinds of pesticides were detected in 715 batches of Vitis vinifera L., with a detection rate of 48.8%, and none exceeded the standard. The food safety index of the detected pesticides and its average value were both below 1, had little impact on the quality and safety of Vitis vinifera L., and the risks were all within an acceptable range. The risk coefficients of the detected pesticides were all below 1.5, which belongs to low risk. Conclusion This study indicates that the quality and safety of Vitis vinifera L. in Shuanghe City, Fifth Division are relatively good, and pesticide residues have no impact on human health. It also provides a reference basis for Vitis vinifera L. cultivation and technical support for the supervision of the quality and safety of agricultural products.

Objective To determine the content of 27 kinds of inorganic elements in commercially available Solanum tuberosum L. in Qinzhou City and evaluate the situation of heavy metal pollution. Methods Quantitative analysis of 27 kinds of inorganic elements in Solanum tuberosum L. was conducted using the inductively coupled plasma mass spectrometry method from GB 5009.268—2016 National food safety standard—Determination of multiple elements in foods. The safety of the samples and the distribution of characteristic elements were comprehensively evaluated by combining the single-factor pollution index method, Nemerow comprehensive index method, and chemometrics based on the toxicity of the elements. Results The commercial Solanum tuberosum L. from Qinzhou City contained abundant trace elements, including the essential constants of human body such as Na (7.50-458.20 mg/kg), Mg (66.40-429.40 mg/kg), K (1620.80-7397.60 mg/kg), Ca (15.00-123.60 mg/kg); essential trace elements such as Mn (0.46-5.16 mg/kg), Fe (3.00-142.10 mg/kg), Cu (0.24-1.12 mg/kg); hazardous elements such as Pb (0-0.08 mg/kg), Cd (0-0.03 mg/kg), As (0-0.08 mg/kg), Cr (0-0.32 mg/kg). The hazardous elements Hg, Sn, Ni were not detected. The content of potentially harmful elements was low, indicating good safety. Single-factor pollution index and Nemerow comprehensive index analyses demonstrated that the single-factor pollution index values and Nemerow comprehensive index values for Pb, Cd, total Hg, total As, and Cr in all samples were less than 0.7, categorizing them as excellent grade with safe pollution levels. Principal component analysis identified Li, Al, Ti, V, Cr, Mn, Fe, As, Mg, K, Cu, Zn, Na, Ca and Sr as characteristic inorganic elements. Cluster analysis classified the samples into two major categories. Conclusion The Solanum tuberosum L. are sold in the market in that city, which has a very low content of harmful elements and a low degree of pollution, and the content does not exceed the limit requirements of GB 2762—2022 National food safety standard—Maximum levels of contaminants in foods. Therefore, all the tested Solanum tuberosum L. samples are safe food, and their growing environment is not polluted by heavy metals.

Liquid fermentation technology has garnered significant attention since the mid-20th century and continued to advance with the evolution of biotechnology. Its advantages lie in shortening culture cycles, enhancing strain activity and purity, and reducing production costs, among other benefits. As a critical component of liquid fermentation technology, edible fungus liquid fermentation enables efficient production of mycelium and bioactive metabolites through optimization of medium components, fermentation parameters and metabolic regulation pathways. This paper reviewed the research progress of edible fungus liquid fermentation technology, with a focus on its advantages, challenges and application prospects in production processes. Through liquid fermentation, not only can the production efficiency of edible fungus mycelium be improved, but also bioactive components such as polysaccharides, terpenoids and peptides can be effectively extracted. These components possess diverse biological activities, including anti-tumor, antioxidant and immunomodulatory effects, holding significant importance for the food and pharmaceutical industries. In addition, the application of liquid fermentation technology for edible fungi in producing fungal metabolites and flavor substances has also demonstrated remarkable potential, providing the food industry with abundant natural ingredients. Based on current research achievements, this paper analyzed the key factors, development trends and major challenges faced by liquid fermentation technology in the edible fungi industry, and prospected the application directions and prospects of this technology in food, pharmaceuticals, and other fields. This review provides a theoretical reference for the efficient production of mycelia and active metabolites, and facilitates the translational application of edible fungus liquid fermentation in various fields.

Objective To optimize the enzyme-assisted extraction process of Eucommia ulmoides leaf extract, and evaluate its antioxidant and hepatoprotective activities. Methods Using Eucommia ulmoides leaves as raw material, the enzyme-assisted extraction technique was employed to optimize the extraction process. The antioxidant activity of the extract was evaluated through 1,1-diphenyl-2-picrylhydrazine (DPPH) radical scavenging rate, hydroxyl radical scavenging rate, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging rate, and total antioxidant capacity assays. The hepatoprotective activity was assessed using a zebrafish model. Results Under the conditions of a solid-to-liquid ratio of 1:20 (g:mL), enzymolysis temperature of 50 °C, enzymolysis time of 4 h, and enzyme dosage of 3%, the yield of Eucommia ulmoides leaf extract was 32.15%±0.36%, with a theoretical yield of 31.781%. The small difference between the actual and theoretical yields indicates the reliability of the extraction parameters. In vitro antioxidant activity tests showed that, within the experimental mass concentration range, the extract exhibited significant antioxidant activity, effectively scavenging DPPH radicals, hydroxyl radicals, and ABTS radicals. Zebrafish experiments demonstrated that the extract at mass concentrations of 100 μg/mL and 200 μg/mL protected against thioacetamide (TAA)-induced liver injury, indicating notable hepatoprotective activity. Conclusion The Eucommia ulmoides leaf extract obtained through enzyme-assisted extraction possesses excellent antioxidant and hepatoprotective activities. This study provides technical support for the further application and promotion of Eucommia ulmoides leaves in the food field.

Objective To study the preparation and physicochemical properties of polypeptide-selenium chelate from Juglans regia L.. Methods Juglans regia L. protein was extracted by alkali-soluble acid precipitation method, and Juglans regia L. polypeptide was prepared by alkaline protease. Juglans regia L. polypeptide reacted with sodium selenite to produce Juglans regia L. polypeptide-selenium chelate. The preparation technology was optimized by single factor test and orthogonal test. Results When the mass ratio of polypeptide to sodium selenite was 3:1, the chelating temperature was 45 ℃, the chelating time was 50 min, and the pH was 8, the chelating rate was 58.99%±1.44%. The chelate was resistant to heat, acid and alkali, had good digestive stability and high bioavailability of selenium. Compared with Juglans regia L. polypeptide, Juglans regia L. polypeptide-selenium chelate had stronger scavenging ability of 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical, hydroxyl free radical and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) cation free radical. Conclusion In this study, Juglans regia L. polypeptide-selenium chelate is successfully prepared through optimized synthesis conditions. The resulting complex demonstrates favorable physicochemical properties and significant antioxidant capacity, providing a potential raw material reference for developing selenium-enriched nutritional supplements.

Objective To optimize the mixed acid extraction process of pectin from Akebia trifoliate peel and evaluate the structure, and antioxidant properties of pectin. Methods Using Akebia trifoliate peel as raw material, which was extracted by the mixed acids hydrolysis. The effects of the types of inorganic acids, the volume ratio of the mixed acid, solid-to-liquid ratio, pH, extraction time and temperature were studied, and Box-Behnken response surface method was used to optimize the extraction process parameters on the basis of single factor experiment. The structure of the peel pectin of Akebia trifoliate obtained under the optimal extraction conditions was characterized by ultraviolet-visible spectroscopy (UV-Vis) and Fourier transform infrared spectroscopy (FT-IR), and its antioxidant activity was investigated. Results The optimal extraction conditions were: The volume ratio of the mixed acid [V(citric acid):V(sulfuric acid)] 2:1, solid-to-liquid ratio 1:30 (g:mL), pH value 1.0, extraction time 2.0 h and temperature 94 ℃, and the extraction rate reached 14.22%, which were about 1.24% and 4.17% increase compared with single sulfuric acid and citric acid, respectively. FT-IR showed that the absorption peaks of sulfuric acid and citric acid extraction of pectin (CSEP) were more consistent with its structural characteristics than sulfuric acid extraction of pectin (SEP) and citric acid extraction of pectin (CEP) at 1754 cm^-1 and 1624 cm^-1, and its content of galacturonic acid (81.94%) and degree of esterification (82.41%) more higher. CSEP own superior antioxidant biological activity, and the half maximal inhibitory concentration (IC₅₀) for hydroxyl radical of CSEP was lower than that of commercial pectin (CP), which were 2.248 mg/mL and 4.114 mg/mL, respectively. Conclusion Using the mixed acid to extract pectin from Akebia trifoliata peel has good improved on extraction rate, content of galacturonic acid and antioxidant activity.

Objective To investigate the protective effects of ethanol extract of Chuangxiong tea on the 2,2'-azobis(2-methylpropionamidine) dihydrochloride (AAPH) (1 mmol/L) on oxidative stress injury of proximal renal tubule epithelial cells of pigs. Methods LLC-PK1 cells were co-cultured with ethanol extract of Chuanxiong tea (labeled CXTEE) with different mass concentrations ranging from 10 to 100 μg/mL for 24 h, and then placed in Dulbecco's modified eagle medium (DMEM) containing AAPH for 4 h to establish the cell damage model. The cell survival rate was measured by tetramethyl azazole blue (MTT) method. The content of malondialdehyde (MDA) and the level of total reactive oxygen species (ROS) were determined by thiobarbituric acid colorimetry and 2',7'-dihydrodichlorofluorescein yellow diacetate (DCFH-DA) probe technique, respectively. In addition, the activity of several antioxidant enzymes, including catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), glutathione S-transferase (GST), γ-glutamylcysteine synthetase (γ-GCs), and the concentration of glutathione (GSH), were also evaluated using specific kits. Results The results showed that the cells pretreated with CXTEE showed a higher survival rate, and the total ROS level and MDA production in the cells were significantly reduced. At the same time, the extract also enhanced the activity of antioxidant enzymes (such as CAT, SOD, GSH-Px and GST) in the damaged cells, promoted the activity of γ-GCS and increased the content of GSH. Further experiments showed that CXTEE could also up-regulate the mRNA expression levels of SOD, GSH-Px and CAT in oxidative damage LLC-PK1 cells. Conclusion The ethanol extract of Chuangxiong tea may reduce the levels of MDA and ROS by strengthening the antioxidant defense system of cells, thus alleviating the oxidative stress damage caused by AAPH to LLC-PK1 cells. This study can provide a basis for further application and development of Chuangxiong tea.

Objective To investigate the effects of Tuo tea flavonoids on D-galactose-induced aging mice in delaying aging and inhibiting inflammation. Methods The anti-aging efficacy of Tuo tea flavonoids were evaluated by measuring weight change, organ index and specific indicators in serum and tissue samples of aged mice treated with Tuo tea flavonoids. Results Tuo tea flavonoids could effectively prevent weight loss caused by aging, and also had a significant effect on preventing the shrinkage of key organs such as the thymus and brain. In addition, the compound also increased the levels of total antioxidant capacity (T-AOC), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in the blood and liver of aging mice, while reducing the concentrations of malondialdehyde (MDA) and nitric oxide (NO). At the same time, the levels of inflammation-related interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) cytokines in serum of aging mice were decreased. Further studies showed that in liver tissues, the expression levels of neuronal nitric oxide synthase (nNOS), endothelial nitric oxide synthase (eNOS), manganese superoxide dismutase (Mn-SOD), copper zinc superoxide dismutase (Cu/Zn-SOD) and catalase (CAT) mRNA increased. The inducible nitric oxide synthase (iNOS) showed a decreasing trend. Especially when the dose reached 100 mg/kg, the Tuo tea flavonoids showed better effects than the same dose of vitamin C. Conclusion As a natural product with potential life-prolonging function, the Tuo tea flavonoids show good biological activity.

Carbamate pesticides are synthesized by substituting amino group onto the carbonyl group of carbamic acid derivatives, and are widely used in agriculture because of their short environmental persistence and low residue accumulation. However, due to unreasonable use, the residues of such pesticides and their metabolites in agricultural products far exceed the national standard limits. Long-term consumption of food containing carbamate pesticide residues will induce nervous system diseases, along with carcinogenic, teratogenic and mutagenic effects on the human body, and lead to death in serious cases. Therefore, it is very important to monitor the residues of carbamate pesticides and their metabolites in agricultural products in real time to ensure food safety. This paper summarized and analyzed the commonly used pre-treatment technologies and detection methods of carbamate pesticides in agricultural products, introduced the characteristics of different pre-treatment technologies such as liquid-liquid extraction, solid-phase extraction and QuEChERS method for the extraction of these pesticides, and introduced the detection methods of enzyme inhibition assays and instrument analysis method respectively. The application characteristics of different detection methods for pesticide residues were analyzed, and new detection technologies and methods were prospeced, in order to provide references for the detection and safety supervision of carbamate pesticide residues in agricultural products, so as to ensure food safety and public health.

Objective To analyze the quality characteristics of Ripe Pu-erh tea from Pu'er City. Methods A total of 43 local fermented Ripe tea samples were collected from Pu'er City, and the quality characteristics of this batch of products were systematically analyzed by sensory evaluation combined with biochemical component detection. Results The color dry tea leaves were brown or reddish brown; the infusion were brown red or reddish brown; the aroma were mellow aged fragrance; the taste had typical pure characteristics of stale aroma; the infused leaves were reddish-brown and soft. Biochemical detection data showed that the content of tea sample water extract, tea polyphenols, free amino acids, soluble sugar and theabrownin in these tea samples were 38.7%-51.5%, 4.55%-11.16%, 1.56%-2.89%, 3.49%-8.27% and 6.84%-12.82%, respectively. The total content of catechins and flavonols were 6.76-18.23 mg/g and 0.18-1.90 mg/g, respectively. The content of theophylline and caffeine were 0.01-0.12 mg/g and 15.21-27.31 mg/g, respectively. The content of gallic acid was 1.22-6.56 mg/g. Conclusion Compared with the Ripe Pu-erh tea from other regions, Pu'er City-fermented tea samples demonstrates significantly higher levels of water extract, soluble sugars and free amino acids, coupled with relatively lower caffeine content. This distinctive biochemical composition corresponds to their sensory profile characterized by a thick mellow taste, pronounced sweetness, and reduces bitterness in the tea infusion. The study systematically delineates the sensory quality attributes and biochemical reference ranges of Ripe Pu-erh tea fermented in Pu'er City, providing scientific data support for future cross-regional comparative studies on the quality characteristics of Pu-erh tea.

Objective To establish a method for the determination of 9 kinds of organic acids (oxalic acid, tartaric acid, quinic acid, malic acid, lactic acid, citric acid, fumaric acid, succinic acid and gallic acid) in fruits and vegetable crisps by liquid chromatography-high resolution mass spectrometry (LC-HRMS). Methods The samples were cleaned up by a SAX solid-phase extraction column. The samples were eluted with 0.1% formic acid in water and methanol as mobile phases and separated on an Eclipse Plus C₁₈ column (4.6 mm×250 mm, 5 μm), and monitored in electron spray ionization (ESI)- mode and quantified by external standard method. Results The calibration curves for 9 kinds of organic acids showed good linearity in the concentration range of 50-5000 ng/mL. The correlation coefficients (r) were all greater than 0.9991, the limits of detection (LODs) were in the range of 1-10 ng/mL, the limits of quantitation (LOQs) were in the range of 10-50 ng/mL, the spiked recoveries were in the range of 96%-98%, and the relative standard deviations (RSDs) were in the range of 1.5%-4.9%. Among them, lactic acid [(16.16±0.30) mg/g] and citric acid [(15.53±0.11) mg/g] were the main organic acids in the fruit and vegetable crisps, and their content was significantly higher than those of other organic acids. In contrast, tartaric acid [(1.29±0.11) mg/g] and oxalic acid [(1.56±0.25) mg/g] were found at lower levels. Conclusion The method is simple, rapid, and accurate and can be used for the qualitative and quantitative determination of organic acids (oxalic acid, tartaric acid, quinic acid, malic acid, lactic acid, citric acid, fumaric acid, succinic acid and gallic acid) in fruit and vegetable crumbles as well as other food.

Objective To establish spectrophotometric method for the rapid determination of the content of 4 kinds of polyethylene nonionic surfactants. Methods The complex formed by the reaction between polyethylene-type nonionic surfactant and iodine solution exhibits corresponding light absorption at a specific wavelength. Based on the direct proportionality between the absorbance value and the concentration of the polyethylene-type nonionic surfactant, this relationship can be utilized for quantitative determination. The influences of absorption wavelength, temperature, time and other factors on the determination of nonionic surfactants were studied to achieve the best reaction conditions. Results The detection conditions were: Wavelength at 525 nm, 10 min and 25 ℃. Good linearity was observed in the range 0-30 mg/L, and the correlation coefficients were ranged from 0.9962 to 0.9988. The limits of detection were ranged from 0.0012 to 0.0022 mg/L. The relative standard deviations of samples were ranged from 0.9% to 5.1%, and the spiked recoveries were ranged from 87.2% to 91.7%. Conclusion The method is simple, accurate and credible, which is suitable for rapid detection of polyethoxylated nonionic surfactants.

Objective To optimize the extraction process of total polyphenols in Artemisia capillaris and study the content of it in Henan Province. Methods A single factor optimization combined with response surface optimization was used to establish the optimal method for extracting total polyphenols from Artemisia capillaris, mainly examining the effects of solid-liquid ratio, ethanol volume fraction, extraction time and extraction temperature on the extraction of total polyphenols from Artemisia capillaris. The samples of Artemisia capillaris were taken from 18 cities in Henan Province, and the total polyphenol content in Artemisia capillaris was analyzed based on soil type and distribution area. Results The best values of 4 factors were as follows: Solid-liquid ratio 1:30 (m:V), ethanol concentration 50%, extraction time 72 min, extraction temperature 63 ℃, and the best extraction rate of total polyphenols was 1.85%. With the best values of 4 factors, the total polyphenols in Artemisia capillaris from 18 regions in Henan was determined and analyzed. The highest value appears in Anyang and the lowest value appears in Zhengzhou. According to the types of soil, the tide soil had the highest value of total polyphenols, which was 7.51 mg/g, and the paddy soil had the lowest value of total polyphenols, which was 6.15 mg/g. Conclusion The method optimized by this study is stable, reliable and economy. The model established can predict the extraction rate of total polyphenols well. The content of total polyphenols in Artemisia capillaris from different regions in Henan is discrepant. But the discrepancy is not significant according to the soil types.

Objective To develop an ultra performance liquid chromatography-tandem mass spectrometry method for the determination of Nisin residues in various foods. Methods The samples were extracted with 0.1% formic acid solution+acetonitrile (80:20, V:V), delipid with n-hexane, eluted with 0.1% formic acid solution and acetonitrile as mobile phase gradient, and separated by ZORBAX Eclipse Plus C₁₈ (100 mm×2.1 mm, 1.8 μm). Electrospray ion source and positive ion multi-reaction monitoring mode were used for detection, and matrix matching standard curve external standard method was used for quantification. Results The linear relationship between Nisin A and Nisin Z was good in the range of 0.5 to 50.0 μg/mL, and the correlation coefficient was greater than 0.995. The limits of detection and quantitation were 0.05 to 0.30 mg/kg and 0.15 to 1.00 mg/kg, respectively. The recoveries ranged from 88.8% to 106.2% and the relative standard deviations were 1.32% to 8.85% at the 3 added levels of 1.0, 5.0 and 200.0 mg/kg. Conclusion The established method is fast, efficient, repeatable, sensitive and accurate, and can be used for the determination of Nisin A and Nisin Z in batch food samples.

Objective To optimize the processing technology of red glutinous sorghum cookies by response surface methodology. Methods Based on single-factor experiments, the sensory score of red glutinous sorghum cookies was taken as the response value, and the process of red glutinous sorghum cookies was optimized by response surface methodology. Results Based on the basic ratio of total flour 500 g, with other ingredients accounting for the proportion of total flour as butter 75.6%, powdered sugar 37.8%, milk 5.5%, and whole egg liquid 16.8%, and using a 12-tooth piping tip for shaping, the optimal process was that the proportion of red glutinous sorghum flour in the total flour was 53%, the baking time was 24 min, and the baking temperature was 158 ℃. Through verification, the cookies made under these conditions had a complete shape, an attractive color, a crispy texture, and the best sensory quality. Conclusion This process is stable and reliable for processing glutinous sorghum cookies, and the research results can provide theoretical support for the processing of glutinous sorghum cookies.

Objective To establish a rapid visual detection method for Aspergillus niger in Zea mays L. by loop-mediated isothermal amplification (LAMP) technology. Methods Based on LAMP technology, specific primers targeting the key ochratoxin A (OTA) biosynthesis gene OTAhal were designed. Through screening of the primers and optimization of conditions such as primer sequence, primer ratio, reaction temperature and visual dye, the optimal detection conditions were determined. Using the total DNA of Aspergillus niger and artificially contaminated corn samples as templates, the sensitivity of the detection method and the feasibility of its practical application were validated. Results The optimal primer ratio was 8:4:1, the optimal reaction temperature was 64 °C, and the method could complete the amplification of target DNA within 30 minutes. The color of the positive sample changed from violet to blue-purple. This method could detect DNA concentrations as low as 6.87×10⁻³ ng/μL. When applied to actual Zea mays L. sample testing, it achieved a detection limit as low as 10¹ spores/mL. Conclusion This method is simple to operate, highly sensitive, and does not require sophisticated instruments. It can be applied to the detection of OTA in actual Zea mays L. samples, indicating broad application prospects.

Objective To study on the improvement of incubation time and plate load capacity for molds enumeration. Methods Mold quality control samples were tested according to GB 4789.15—2016 National food safety standard-Food microbiological examination-Enumeration of moulds and yeasts, with additional colony counting performed on the second day of incubation. The plate size was increased from 90 mm to 150 mm, and statistical analysis was employed to assess the differences between colony counts and the reference value of the quality control samples. Results Significant discrepancies were observed between the fifth-day counting result at the critical dilution (1:10) and the reference value. A sharp decline in colony counts was noted when the colony-forming units exceeded 30 CFU per 90 mm plate, which was defined in this study as the maximum load capacity of mold plates under acceptable accuracy. By adopting 150 mm plates with a 2-day incubation period, the original load capacity was overcome, yielding counting results that aligned well with the reference value. Under these optimized conditions, the linear coefficient of determination (R²) between sample means and dilution factors improved from R²₉₀=0.614 to R²₁₅₀=0.998. Conclusion The optimized testing conditions effectively addressed the issues of colony overgrowth and poor linearity in mold plate count experiments, thereby enhancing the accuracy of test results.

Objective To establish a method for the simultaneous determination of 19 kinds of common preservatives, sweeteners and synthetic colorants in beverages by high performance liquid chromatography (HPLC). Methods HPLC was employed with an ACE Excel 5 C₁₈ column (4.6 mm×250 mm, 5 μm) at a flow rate of 1.0 mL/min. Gradient elution was performed using 20 mmol/L ammonium acetate (pH 7.5) and methanol as the mobile phases, and detection was carried out using a diode array multi-wavelength detector. Results Effective separation of all 19 kinds of food additives was achieved. The linear range of the method was 0.5-50.0 μg/mL, with correlation coefficients above 0.9998. The average recovery rates ranged from 92.26% to 104.59%, with relative standard deviations (RSDs) between 0.45% and 1.67%. The limits of detection were 0.07-0.29 mg/kg, and the limits of quantitation were 0.23-0.96 mg/kg, both of which were below the national standards and met the detection requirements. Conclusion This method is simple to operate, requires short pre-treatment time, provides good separation efficiency, accurate data, and high sensitivity, making it suitable for the simultaneous determination of 19 kinds of food additives in beverages.