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.

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 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.

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 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 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.

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 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 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.