Objective To explore the antioxidant effects and fatty acid content of walnut oil derived from different substrates. Methods Gas chromatography-mass spectrometry (GC-MS) was used to analyze the fatty acid content in walnut oil and unqualified walnut oil at different pressing temperatures. Single variable control method was used to study the antioxidant effects of walnut oil with different air content. After adding a complex of natural antioxidants, fat soluble rosemary at 0.04 g/100 g and vitamin E at 0.1 g/100 g, 2 sets of experiments were conducted. The first set contained 100, 200, 300, 400 and 500 mL oil samples in 500 mL glass bottles, while the second set contained 100 mL oil samples in 100, 250 and 500 mL glass bottles. The samples were rapidly oxidized in a constant temperature drying oven at 63 ℃±1 ℃ and kept at that temperature for 70 days. The aroma, taste, peroxide value and acid value of the oil samples were measured every 10 days. Results The fatty acids in walnut oil were palmitic acid, linoleic acid, stearic acid and oleic acid. The content of fatty acids varies with storage time and pressing temperature, and the unqualified oil sample didn’t contain oleic acid. The walnut oil pressure pressing temperature of 130-140 ℃ had the best quality. The 2 sets of experiments had confirmed that walnut oil with lower air content could be stored for a longer period of time, up to a maximum of 100 days. Conclusion The less contact with air during storage or the decrease in the ratio of initial air volume to initial oil sample volume, the longer the shelf life. The conduct of this study provides a reference for the storage conditions of walnut oil.

Objective To investigate the sensory changes of camel meat stored at different temperatures (4, 15, and 25 ℃) and establish a shelf-life prediction model based on sensory differences. Methods By simulating actual storage conditions, the changes in color, electronic tongue taste indices (umami, saltiness, sourness, sweetness, etc.), and electronic nose olfactory indicators (nitrogen oxides, methane, sulfides, etc.) of camel meat were analyzed. Zero-order reaction kinetics models and the Arrhenius equation were used to fit the data, establishing a shelf-life prediction model based on color, electronic tongue and electronic nose metrics. The model was validated using pH, total bacterial count and total volatile basic nitrogen (TVB-N). Results At 4 ℃, there was no significant change in the lightness (L^*) and redness (a^*) of camel meat (P>0.05), while the a^* value significantly decreased at 15 ℃ and 25 ℃ (P<0.05), and yellowness (b^*) showed an upward trend across all temperatures. Taste analysis revealed that umami (AEE), saltiness (CT0), sourness (CA0) and astringency (AE1) intensities increased with time and temperature, whereas sweetness (GL1) intensity decreased. Electronic nose detection found that concentrations of nitrogen oxides (W5S), methane (W1S), sulfides and terpenes (W1W) and alcohol compounds (W2S) significantly increased over storage time. The calculated shelf lives based on color, electronic tongue and electronic nose were 7.23, 6.24 and 6.12 d, respectively. Verification using camel meat stored at 6 ℃ showed high prediction accuracy of the electronic tongue model, but significant discrepancies were observed among shelf lives predicted by different physicochemical indicators (e.g., total bacterial count, pH, TVB-N). Conclusion This study successfully establish a shelf-life prediction model based on sensory characteristics. The prediction models established based on the electronic tongue and electronic nose show good agreement with validation results based on pH, with relative errors of -2.80% and -4.67%, respectively. Different physicochemical indicators have varying degrees of strictness towards meat quality requirements, with total bacterial count being the most stringent and TVB-N relatively more lenient. This study provides a reference for the quality monitoring of fresh camel meat.

Objective To reveal an intuitive understanding of the academic context and evolutionary trends of the pungent studies based on Chili peppers and Sichuan peppers, as well as their key pungent components. Methods Over 10000 articles in the core database of the Web of Science over the past decade had been taken as the research object, and the current status and hotspots of pungent research had been compared and analyzed using the bibliometric analysis methods. Results The pungent study presents a continuous trend of the interdisciplinary integration, where many fields were involved such as plant science, food science and technology, biochemistry and molecular biology, pharmacology and pharmacy, neuroscience and chemistry, and the focuses of the pungent studies were quite different. The number of the publications on the pungent (Là) research was much higher than that on pungent (Má) research. China was the country that had the highest number of publications in the field of both pungent researches, especially in the pungent (Má) research, where China occupied a leading position in the aspects like international cooperation and the influence of the author and research institution. The hot topics and burst keywords in pungent studies had been further revealed through the co-occurrence, clustering and burst occurrence analysis of keywords. Conclusion Currently, the commonality lies in the research on the pungency and biological activity of Sichuan peppers or Chili pepper and their main components. The difference is that the pungent (Là) research mainly focuses on the health and quality of Chili peppers and related foods, while the pungent (Má) research focuses more on the pungency, quality and health effects of Sichuan peppers and its key components. The theoretical basis can be provided for the experts and scholars in the fields of plant science, food science and technology, pharmacy and medicine to grasp the current situation, laws and directions of the pungent research.

Perfluoroalkyl and polyfluoroalkyl substances (PFASs), characterized by their environmental persistence, bioaccumulation potential, hydrophobic and oleophobic properties, and chemical stability, have been extensively applied in industrial production and daily life. However, the widespread presence of these compounds poses significant threats to both ecological systems and human health. Dietary intake, particularly through animal-derived foods (e.g., fish, shellfish, poultry, and their processed products), represents a primary pathway of human exposure to PFASs. To effectively assess their health risks and formulate relevant regulatory policies, it is crucial to establish rapid, efficient, and sensitive detection methods for monitoring PFAS contamination levels in animal-derived foods. This review systematically summarized sample preparation techniques for PFAS analysis in animal-derived foods and highlights advancements in chromatographic and chromatographic-mass spectrometric methods for detection. Furthermore, it provided an overview of current research on PFAS contamination levels across various food matrices, offering critical insights for environmental pollution assessment, food safety regulation, and optimization of analytical technologies.

Objective To optimize the fermentation process of pine pollen rice wine by Box-Behnken response surface design and entropy weight technique for order preference by similarity to an ideal solution (TOPSIS) method. Methods With pine pollen and glutinous rice as the main raw materials, sensory score, alcohol content and antioxidant capacity as evaluation indexes, a 3-factor and 3-level response surface test was designed based on the single factor test, and the addition of pine pollen, koji and fermentation time as investigation factors, according to the Box-Benhnken central combination test principle. The fermentation process of pine pollen rice wine was optimized by entropy weight TOPSIS method. Results The optimum fermentation process of pine pollen rice wine addition was 8%, koji addition 0.8% and fermentation time 72 h. Under these conditions, the texture of pine pollen rice wine was uniform, the taste was soft, and the color was light brown and yellow. After 3 batches of process verification experiments, the sensory score of rice wine was 89.5 points, the alcohol content was 17.2%vol, and the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical clearance rate was 87.43%. Conclusion The method of entropy weight TOPSIS combined with response surface design to optimize the fermentation process of pine pollen rice wine is stable and predictable, which lays a theoretical foundation for the production of high quality pine pollen rice wine.

Objective To explore the mixing ratio of different oil seeds in microwave-assisted blended cold pressing process, and develop polyunsaturated fatty acid balanced oil that meets the recommended dietary intake ratio. Methods The safflower seed and flaxseed were used as raw materials. The process parameters were optimized by single factor experiment (microwave treatment time, pressing temperature and moisture content of oil seed) and Box-Behnken response surface experiment. The oxidation characteristics of blended cold pressed oil were compared and analyzed. Results The mass ratio method determined that the blended mass ratio range was 1.8-2.4 (safflower seed:flaxseed, W_s:W_f). This method was simple and the results did not need to be verified, but it had the disadvantages of large demand for raw materials and low accuracy of boundary value. The mixing ratio range determined and verified by the fatty acid ratio method was 1.66-2.59 (W_s:W_f). This method had less raw material demand and high accuracy near the boundary value. However, due to the interaction of oil seeds, verification experiments needed to be carried out. Response surface methodology was used to optimize the process parameters of microwave-assisted blended cold pressing. The optimal extraction conditions were as follows: Microwave (800 W) treatment time 1.5 min, cold pressing temperature 64 °C, oil seed moisture content 6.7%, oil extraction rate 19.83%±0.21 %, which was 17.2% higher than that before optimization. The basic physical and chemical indexes of blended cold-pressed oil and traditional cold-pressed blend oil were compared and analyzed. The oil oxidation degree was lower under the condition of microwave-assisted blended cold-pressed process. Conclusion Microwave-assisted blended cold pressing oil has lower primary and secondary oxidation product indexes than traditional cold-pressed blended oil. The results can provide a theoretical basis for the preparation of polyunsaturated fatty acid equilibrium oil and the application of microwave-assisted blended cold pressing process in the field of grain and oil processing.

Objective To construct a quality evaluation system for the main-sold pork in Shanghai and analyze the appearance, texture, nutrition, and flavor indicators of different pig breeds. Methods A total of 95 samples of the longissimus dorsi muscles were collected from 7 boar breeds, including Pudong White pigs. Fifty-five parameters were detected. Correlation analysis and radar charts were used to determine the core indicators for quality evaluation. Results In terms of appearance quality, different pig breeds showed differences in indicators such as pH and moisture content. Shawutou pigs, Pudong White pigs and Shanghai White pigs had slightly lower water content, while Shawutou pigs had a high drip loss rate. Topigs had slightly higher intramuscular fat content. Correlation analysis showed that the water content was negatively correlated with 24-hour drip loss. Regarding texture, Fengjing pigs had high shear force, Topigs had high hardness. Correlation analysis showed that the shear force was negatively correlated with hardness and positively correlated with elasticity. In terms of nutritional quality, it showed that the protein content in Shanghai local pig breeds was higher than that in common Duroc-Landrace-Yorkshire pigs. Three-way crossbred pigs and Shanghai White pigs had slightly lower fat content. The proportion of essential amino acids was the lowest in three-way crossbred pigs. In terms of flavor quality, the total amount of umami amino acids in each pig breed was similar. Shanghai White pigs had a high content of cytidine monophosphate, three-way crossbred pigs and Fengjing pigs had a high content of uridine monophosphate, Topigs had a low content of multiple flavor-related nucleotides, and Shawutou pigs had a high content of adenosine monophosphate. Correlation analysis showed that aspartic acid was positively correlated with the total amount of umami amino acids. Conclusion A quality evaluation system for Shanghai pork can be constructed around 13 core indicators, including water content, conductivity, shear force, hardness, resilience, protein, fat, magnesium, potassium, selenium content, adenosine monophosphate, inosine monophosphate, and aspartic acid. In the future, relevant factors need to be comprehensively considered to construct a comprehensive evaluation model.

Objective To screen a strain that can antagonize the growth of Aspergillus flavus and to identify the strain, study its application and analysis its genetic preliminarily. Methods The microorganisms in the soil of peanut field in Feixian County were used as the research object, and the effective strains were obtained through the screening of Aspergillus flavus standoff test; the effective strains species were determined through morphological observation and 16S rRNA gene analysis and identification; the peanut pods and peanut kernels were infested with the suspension of Aspergillus flavus spores to validate the effective bacteria’s effect of antagonizing the growth of Aspergillus flavus; and the genome characteristics of the bacterial strains and the clusters of genes of secondary metabolites synthesis were analyzed to determine the basic characteristics of the effective bacterial strains. The genomic characteristics of the strain and the secondary metabolite synthesis gene cluster were analyzed to determine the basic characteristics of the effective strain. Results Effective strain G22, which could antagonize the growth of Aspergillus flavus, was obtained by screening. The strain G22 was identified as Burkholderia latens with 99.93% homology and named Burkholderia latens G22 by morphological characterization and gene homology analysis. The fermentation broth of the effective strain had a certain antagonistic effect on the growth of Aspergillus flavus on peanut pods and peanut seed kernels. The genome of the effective strain had 3 chromosomes and 1 plasmid, and the secondary metabolite synthesis gene cluster proved that the effective strain had antagonistic properties. Conclusion Strain G22 has good antagonistic effect on the growth of Aspergillus flavus. The application effect of strain G22 in peanut has important research significance in practice, which will lay a foundation for the further development of microbial fungicides for Aspergillus flavus.

Objective To rapidly screen the elemental content and migration of heavy metals in commercially available stainless steel electric kettles using efficient detection technologies. Methods In this study, 20 batches of stainless steel electric kettle samples were analyzed using inductively coupled plasma-mass spectrometry (ICP-MS) to determine the migration levels of 13 kinds of heavy metal elements, along with label compliance checks. A handheld X-ray fluorescence (XRF) spectrometer was employed to rapidly detect the elemental content of key components and analyze their material composition. Results Multi-element migration experiments revealed heavy metal migration in some samples, particularly manganese (Mn) and aluminum (Al). XRF analysis identified the use of non-food-grade stainless steel in certain products. Additionally, non-compliant product labeling and discrepancies between labeled and actual material compositions were observed in some samples. Conclusion The combined ICP-MS and XRF results demonstrat that stainless steel material quality is a critical factor influencing heavy metal migration. This study provides theory basis for enhancing industry quality regulation, ensuring consumer health and safety, and promoting technological advancements in product manufacturing.

Objective To explore the distribution of metal elements in honeycomb and the potential food safety risks. Methods In this study, flame atomic absorption spectrometry was used to determine the content of Cd, Fe, Cr, Mg, Zn, Cu, Mn and Pb in 7 parts (nest membrane, nest column, nest wall, whole nest, adult bee, nest bottom, pupae) of honeycomb samples collected from Yunnan, Guangdong and Guangxi. Results The standard curves exhibited excellent linearity with correlation coefficients (r²)≥0.993, and the method sensitivity met trace detection requirements (limits of detection: 0.002-0.010 mg/kg). Significant differences in metal content was observed among different parts of the honeycombs (P<0.05), with the average concentrations ranked as Mg (0.97 mg/kg)> Zn (0.15 mg/kg)>Mn (0.051 mg/kg)>Cu (0.0385 mg/kg)>Fe (0.02 mg/kg) >Cd (0.0060 mg/kg)>Pb (0.00027 mg/kg)> Cr (0.00003 mg/kg). The distributions of Cd, Fe, Mg, Zn, Cu and Mn showed significant variations across parts (P<0.05), whereas Cr and Pb exhibited no significant differences (P>0.05). The results suggestted that the distribution of essential elements (Mg and Zn) was closely associated with the biological functions of honeycombs, while the localized accumulation of Cd and Pb might reflect environmental contamination. Conclusion This study systematically reveals the spatial distribution characteristics of metal elements in honeycombs, providing a scientific foundation for quality control of bee products and traceability of environmental pollutants.