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

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

Fungi are one of the more common microorganisms in our daily lives, and are closely related to our lives, with both advantages and disadvantages. Its harmful effects are manifested in a number of ways. For example, some fungi can cause crop diseases and reduce yield, accidental consumption of poisonous mushrooms can cause food poisoning and threaten people's lives, in addition, pathogenic fungi can also cause fungal infections and other diseases that are harmful to people's health, so it is very important to be able to quickly and accurately detect pathogenic fungi and identify poisonous mushrooms. Loop-mediated isothermal amplification (LAMP) is a nucleic acid amplification technique widely used in recent years, which uses DNA polymerase and specific primers to amplify nucleic acids with high efficiency in a short period of time under constant temperature conditions, compared with traditional molecular biology methods, this method does not require high instrumentation, and is characterized by rapidity, sensitivity and simplicity. At present, LAMP technology has been widely used in the detection of microorganisms such as bacteria, fungi and viruses, and this paper summarised the application of LAMP technology in the detection of fungi to provide a reference for related research.

Mycotoxins are secondary toxic metabolites produced by fungi during their growth and reproduction. They are widely found in various kinds of grain and oil and their products, and can cause serious threat to human health. Mycotoxin contamination has become a common phenomenon and problem in many countries and regions. Mycotoxin detection is the key link to build a mycotoxin prevention and control system. Furthermore, mycotoxins content is one of the health indicators that must be detected in raw grain and its products. It is of great significance to establish accurate and efficient detection methods for mycotoxins in grain, oil and food to ensure food safety. This paper summarized and analyzed the common detection methods of mycotoxins in grain, oil and food, and mainly introduced the different detection techniques and methods and their application characteristics, such as chromatography analysis, spectral analysis and immunoassay. Futhermore, this paper prospected the development trend and related requirements of mycotoxins detection, so as to provide references for the detection and safety supervision of mycotoxins in grain, oil and food.

Objective To study the characterization and antioxidant activity of Maillard reaction products of autolytic peptides from Stichopus japonicus. Methods The autolysis phenomenon of Stichopus japonicus was taken to dissolve their body walls. Further used D-xylose and Stichopus japonicus autolytic peptides for Maillard reaction to modify autolytic peptides, and the physical and chemical properties and antioxidant activity differences of the Maillard reaction products were analyzed. Results The Maillard reaction conditions were as follows: Reaction time 4 h, reaction temperature 120 ℃, mass ratio of Stichopus japonicus autolytic peptides to D-xylose 1:2. After the reaction, the content of free amino group decreased from (32.35±1.90) μg/mL to (12.68±1.10) μg/mL. The maximum fluorescence emission peak of the Maillard reaction products shifted from 401 nm to 434 nm, and an absorption peak appeared at 288 nm in the ultraviolet absorption spectrum. The molecular weight measurement showed that the large molecular weight material above 3600 u increased significantly. The appearance of the Maillard reaction products from the autolytic peptides of Stichopus japonicus and D-xylose was verified. When the mass concentration of Maillard reaction products was 8 mg/mL, the scavenging ability of hydroxyl free radical, 1,1-diphenyl-2-picrylhydrazine (DPPH) free radical and 2,2’-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) cation free radical were above 85%, and the reducing ability of Fe³⁺ was 6.3 times higher than that of autolytic peptides from Stichopus japonicus before the reaction. Conclusion The results provide a new reference for utilizing the autolysis of Stichopus japonicus and improving the antioxidant activity of the Stichopus japonicus autolytic peptides.

Objective To rapidly and non-destructively detect aflatoxin in mildly moldy Zea mays using near-infrared spectroscopy (NIRS) technology. Methods Mildly moldy Zea mays samples were selected as experimental materials, with the content of aflatoxin B₁ (AFB₁) as the detection indicator. A total of 153 sample images were collected using the NIRS imaging acquisition system. Three kinds of preprocessing methods, including multiplicative scatter correction, standard normal variate transformation, and moving average smoothing (MAS), were applied to preprocess the raw near-infrared spectral data (RNSD). Backpropagation neural network (BPNN), extreme learning machine, and support vector machine were employed to model and analyze the preprocessed spectral data along with AFB₁ content data, evaluating the impact of preprocessing methods on model performance. Furthermore, the stepwise projection algorithm (SPA) was performed to select characteristic spectra from the preprocessed data for comprehensive comparison after incorporating them into the models. Results The optimal spectral preprocessing method was MAS. Ten characteristic spectra were selected through SPA, and the BPNN model exhibited the best prediction results, achieving a coefficient of determination of 0.932 and a relative prediction deviation of 3.922. This model demonstrated good performance and reliability. Conclusion It is feasible to determine AFB₁ content in mildly moldy Zea mays using NIRS technology. The findings of this study provide an important reference for the application of NIRS in identifying other agricultural products.

Objective To develop an ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the determination of pentachlorophenol sodium residues in aquatic products. Methods The sample preparation involved extraction with 80% acetonitrile in water containing 5% triethylamine, followed by purification using Waters Oasis MAX solid-phase extraction cartridges. After elution with a 4% formic acid in methanol solution, the pentachlorophenol sodium was analyzed by UPLC-MS/MS using a Waters XBridge C18 column (100 mm × 2.10 mm, 3.50 µm). The mobile phases consisted of A: 0.1% formic acid in water (containing 5 mmol/L ammonium acetate) and B: acetonitrile. Quantification was carried out using the external standard method. The recovery of pentachlorophenol sodium in the muscle of Ctenopharyngodon idella and the eatable part of Eriocheir sinensis matrices was examined. Results The linear range of the pentachlorophenol sodium residue detection method in Ctenopharyngodon idella and Eriocheir sinensis was 0.2 to 8.0 ng/mL (r²>0.999). The limit of detection was 0.5 μg/kg and limit of quantification was 1.0 μg/kg, respectively. The recoveries at spiking levels of 1.0, 2.0, and 10 μg/kg were within the range of 77.0% to 105%. Intra-assay relative standard deviations ranged from 2.51% to 7.62% (n=6), and inter-assay relative standard deviations ranged from 3.36% to 6.48% (n=3). Conclusion The developed UPLC-MS/MS method for the determination of pentachlorophenol sodium residues in Ctenopharyngodon idella and Eriocheir sinensis matrices is highly sensitive, accurate, and precise, with good repeatability and reproducibility, and is therefore suitable for the detection of pentachlorophenol sodium residues in aquatic products.

Tetracycline antibiotics are widely used in animal husbandry, and their main ways of entering milk are through environmental exposure and direct ingestion by cows. Tetracyclines accumulate toxicity through the food chain and pose a threat to human health. Molecular imprinting technology can customize high molecular network polymers that specifically bind to tetracyclines, with many advantages such as high selectivity, good mechanical properties, low cost, high temperature and acid-base resistance, and reusability. It plays an important role in the detection of tetracycline residues in milk. The combination of molecular imprinting and solid-phase extraction technology can simplify the pretreatment process, optimize methods, and effectively solve the separation and purification problems caused by the complexity of milk matrix, including four solid-phase extraction and chromatography techniques: Solid-phase extraction, solid-phase microextraction, dispersed solid-phase extraction, magnetic solid-phase extraction, etc. The specific recognition ability based on molecular imprinting technology combined with sensors (including 5 types of sensors: Molecular imprinting electrochemistry, fluorescence, photonic crystal, plasma resonance, and photoelectric sensors) can improve selectivity, stability, and response speed. The operation is simple, especially suitable for rapid screening on site. This article introduced the research progress of the above-mentioned technologies and sensors in detecting tetracycline residues in milk, analyzed and discusses their application effects, and pointed out the future direction of molecular imprinting technology in this field, providing reference for subsequent research and application.

There are many types of pollutants in food, and exposure involves multiple stages such as raw material, processing, transportation, storage, packaging, and sales. With the improvement of people's requirements for the healthy, nutritive and safe condiments, the pollutants in food have received more and more attention. Liquid chromatography-high resolution mass spectrometry (LC-HRMS) combines the separation ability of liquid chromatography with the advantages of high resolution mass spectrometry, such as wide mass range, fast scanning speed, and high sensitivity, making it an important means in the field of food safety analysis. This review summarized the technical characteristics of quadrupole-time of flight mass spectrometry and quadrupole-orbitrap mass spectrometry, as well as the research progress in the detection of pollutants in food using LC-HRMS technology over the past 5 years. The article focused on the application of LC-HRMS in the targeted and non-targeted determination of pesticides residues, veterinary drugs and their metabolites, food additives, illegal additives and mycotoxins, and prospected the development trend. Aiming to provide reference for the detection of pollutants in food in the future.

Objective To investigate the effects of different storage conditions on the water migration and volatile component changes of Zea mays, and to screen out characteristic volatile components. Methods Low field-nuclear magnetic resonance (LF-NMR) and gas chromatography-ion mobility spectrometry (GC-IMS) technology were used to study the changes in micro moisture, volatile component composition, and relative content of Zea mays under controlled temperature and humidity conditions. Results With the extension of storage time, moisture, fatty acid value, starch, and alcohol soluble protein indicators all undergo certain changes. When stored for 30 days, the moisture content reached equilibrium; the maximum value of fatty acid value was 46.11 mgKOH/100 g when stored at 65% RH for 90 days at 30 ℃, and the fatty acid value was still suitable for storage after 120 days; storing at 20 ℃ was beneficial for the accumulation of starch content; alcohol soluble proteins were significantly affected by temperature; under 65% RH conditions, as the storage temperature increased, the bound moisture content gradually decreased, resulting in the transformation of T20 strongly bound water to T21 weakly bound water and T22 strongly bound water to T23 weakly bound water; under 55% RH conditions, as the storage temperature increased, the bound water content gradually decreased, and the changes in the peaks of non flowing water and free water were consistent with those of bound water; the volatile components in the sample were classified as acids (2 types), aldehydes (20 types), ketones (15 types), alcohols (15 types), esters (12 types), furans (2 types), olefins (3 types), and amines (1 type). Conclusion As the storage temperature increases, the ability of Zea mays to retain moisture gradually weakens, while as the humidity increases, its ability to retain moisture increases. The high temperature and high humidity environment promotes the release of volatile components such as aldehydes and alcohols, while ketones and esters decrease. The 3-pentanone, 1-octen-3-one-M, 1-butanol, 3-methyl-D, 1-hexanol-D, isovaleric acid, methyl ester can be used as characteristic volatile components to distinguish mold growth in high moisture Zea mays, providing reference for the identification of mold growth in high moisture Zea mays.