Objective To optimize a compound desulfurizer of pickled pepper raw material by principal component analysis and response surface method. Methods The limit of detection was based on GB 2760—2014 National standard for food safety-Standards for the use of food additives, selected 3 kinds of desulfurizers with good desulfurization effect and little influences on raw material quality from 9 kinds of common desulfurizers by single factor experiments, designed a 3-factor, 3-level experiment by response surface method, through principal component analysis and response surface analysis, the optimum compound ratio and the optimum operating conditions were obtained. Results When the mass fraction of calcium hydroxide was 44.05%, sodium bicarbonate was 35.57%, chlorine dioxide was 20.38%, and the concentration was 0.10%, the desulfurization rate could reach 94.55%, which was about 36.50% higher than that of no use. At the same time, the color and hardness of pickled pepper materials had no obvious changes. Conclusion The study obtains a kind of compound desulfurizer with good desulfurization effect and little influences on raw material quality, and has high application value.

Objective To establish an analytical method for the determination of selenium content in beef and offal (beef heart, beef liver, beef lung) using microwave digestion-hydride atomic fluorescence spectrometry (HG-AFS). Methods Based on 2 factors, namely the feeding amount and feeding time of the cattle, 80 simmental bulls weighing around 500 kg (±10 kg) were selected and randomly divided into 4 groups: A, B, C and D. Groups A, B and C served as experimental groups, while group D was the control group, with 20 cattle in each group. Selenium in beef and offal samples was digested using a nitric acid-hydrogen peroxide (HNO₃-H₂O₂) microwave digestion method, with potassium borohydride as the reducing agent and 10% hydrochloric acid as the carrier stream, at a digestion temperature of 190 ℃. Results Selenium exhibited a good linear relationship within the mass concentration range of 0-20 ng/mL, with a correlation coefficient (r)>0.999. The average spike recovery rates (n=3) for samples A, B, C and D were 86.9%, 82.4%, 87.9% and 83.8%, respectively. Conclusion This study provides data support and a reference basis for the determination of selenium content in selenium-enriched cattle products and the development of selenium-enriched functional agriculture.

Plant-based raw materials refer to materials extracted from or derived from plants, with dietary fiber and protein as the main ingredients, which can be used in many fields such as food, industry, and environmental protection. At present, with the consumer quest for “health and sustainability” and the demand of lactose intolerant and vegetarian groups, plant-based protein materials are widely used in the dairy industry to produce nutritious (zero cholesterol and low saturated fat), humane (animal welfare) and environmentally friendly (energy saving and emission reduction) animal milk alternatives. This paper reviewed the research progress on the quality characteristics of plant-based protein raw materials and their application in the dairy industry, and provided a certain reference for the research and application of plant-based materials in the dairy industry.

With the wide application of strains in food field, its safety has been paid more and more attention. Safety evaluation includes domestic and foreign safety evaluation data, whole genome sequencing, animal pathogenicity test, drug resistance test, etc. Among them, pathogenicity refers to the ability of microbial strains to infect the host and cause health damage and diseases, and is an important project of strain safety evaluation. The paper systematically investigated the safety management regulations and animal pathogenicity evaluation requirements of strains in food field at home and abroad, and conducted a comprehensive comparative analysis of the reported animal pathogenicity evaluation methods, aiming to lay a foundation for the application of animal pathogenicity evaluation in the safety evaluation of strains in food and other fields in China.

Objective To establish a qualitative and quantitative analytical method for determination of short-chain fatty acids in table salt using headspace solid phase microextraction arrow-gas chromatography-mass spectrometry. Methods A phosphoric acid solution was added to the salt samples, and the headspace solid phase microextraction arrow technique was employed to extract and enrich the short-chain fatty acids. The effects of extraction fiber, extraction temperature, extraction time, and incubation time on the extraction efficiency were investigated. The target compounds were detected by gas chromatography-mass spectrometry and quantified using the external standard method. Results The 100 μm Polyacrylate extraction fiber demonstrated good selectivity for short-chain fatty acids. Under optimal conditions (extraction temperature of 40 °C, extraction time of 30 min, desorption time of 5 min and incubation time of 20 min), the method showed excellent linearity for 9 kinds of short-chain fatty acids, with correlation coefficients greater than 0.995. The limits of detection ranged from 0.25 to 25.00 μg/kg, the recovery rates were between 92.2% and 100.1%, and the relative standard deviations ranged from 1.4% to 9.4%. Conclusion The established method for analyzing short-chain fatty acids in table salt is characterized by simple sample preparation, high sensitivity, good recovery rates and stability, making it suitable for the detection of short-chain fatty acids in table salt.

Objective To establish a quantitative detection method for the quantitative determination of the viable bacteria number of Bifidobacterium animalis subsp. lactis BB-12 and Lactiplantibacillus plantarum ST-III in fermented milk, by combining propidium monoazide (PMA) with real-time fluorescence quantitative polymerase chain reaction (qPCR). Methods Firstly, the specific primer probe of Bifidobacterium animalis subsp. lactis BB-12 and Lactiplantibacillus plantarum ST-III was designed and verified, the standard curve was established using standard strains, and the reaction conditions of the PMA were optimized. Secondly, the quantities of Bifidobacterium animalis subsp. lactis BB-12 and Lactiplantibacillus plantarum ST-III in the fermented milk samples were quantitatively detected. Results The optimal mass concentration of damaged bacteria of Bifidobacterium animalis subsp. lactis BB-12 and Lactiplantibacillus plantarum ST-III was 10 μg/mL, and the optimal exposure time was 10 min. The PMA-qPCR detection method could accurately detect Bifidobacterium animalis subsp. lactis BB-12 and Lactiplantibacillus plantarum ST-III in fermented milk. Conclusion In this study, a rapid and accurate PMA-qPCR detection method is established for the detection of Bifidobacterium animalis subsp. lactis BB-12 and Lactiplantibacillus plantarum ST-III in fermented milk system, which provides certain reference significance for the quantitative detection of probiotics in fermented milk products.

Objective To prepare a multifunctional chitosan-based composite film and improve its application in fruit preservation. Methods A kind of chitosan/lignin/ε-polylysine composite film was fabricated, and its effects on the postharvest preservation of Citrus reticulate ‘Shiyue Ju’ and Vaccinium spp. were also investigated. Results The results showed that although the addition of lignin made the film brown, the good transparency, excellent water resistance and antioxidant property were also observed in the obtained film. Moreover, the results showed that the composite film loaded with 0.2% ε-polylysine exhibited 100% inhibition rate against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coil). The preservation experiment results indicated that, under the optimized film composition conditions (2.0% chitosan, 0.023% lignin, 0.2% ε-polylysine), the chitosan/lignin/ε-polylysine composite film could effectively delay the changes of physical and chemical properties during the fruits storage. After 12 days of storage at room temperature, compared with the blank groups (untreated Citrus reticulate ‘Shiyue Ju’ and Vaccinium spp.), the composite film-treated Citrus reticulate ‘Shiyue Ju’ and Vaccinium spp.’s rot rate decreased by 22.22% and 62.50%, the weight loss rate decreased by 3.22% and 3.67%, as well as the hardness of Citrus reticulate ‘Shiyue Ju’ increased by 35.59% and the hardness of Vaccinium spp. increased by 2.02%, respectively. At the same time, the composite film effectively maintained the content of soluble solids, vitamin C (VC), titratable acid and other nutrients in Citrus reticulate ‘Shiyue Ju’ and Vaccinium spp.. Conclusion The prepared chitosan/lignin/ε-polylysine composite film is expected to replace chemical preservatives in the preservation of oranges and blueberries, providing a reference for the development of novel green preservation materials.

Objective To explore the optimal aging time for high-quality beef. Methods The longissimus dorsi muscle of Wokin black cattle was selected as the experimental material. The beef was aged in a chilling room at 4 °C for 12, 24, 48, 72, 96, and 120 hours. Comprehensive analyses were conducted on the beef’s moisture content, pressurized water loss rate, tenderness, inosinic acid, amino acids and fatty acids. Principal component analysis was performed on tenderness and flavor composition indicators under different aging times. Results The moisture content of beef showed no significant differences among different aging times (P>0.05). The pressurized water loss rate gradually increased with prolonged aging time, reaching its maximum value of (34.84±0.39)% at 120 hours. Tenderness gradually decreased, reaching its lowest value of (24.42±5.04) N at 120 hours. The inosinic acid content peaked at (185.2±10.3) mg/100 g after 72 hours of aging. Umami and sweet amino acids reached their highest levels at 96 hours, while bitter amino acids reached their lowest levels at 12 hours. The content of saturated fatty acids+monounsaturated fatty acids, Methyl stearate (C18:0), and methanol oleate (C18:1n9c) were highest at 120 hours. Principal component analysis and comprehensive factor scoring results indicated that the tenderness and volatile flavor compounds of beef aged for 96 hours scored significantly higher than those aged for other durations. This aging time was most conducive to the formation of volatile flavor compounds in beef. Conclusion Aging for 96 hours is beneficial for enhancing the tenderness and flavor of high-quality beef.

Objective To further explore and optimize the wet fermentation process of small grain coffee, and conduct quality analysis on the coffee produced under this process condition. Methods Firstly, the selected small coffee fresh fruits were cleaned and peeled, and then natural microorganisms were introduced in a waterproof environment for full fermentation. After fermentation, the mucus was removed, and it was dried properly to complete the entire wet fermentation process. In the coffee quality experiment, a fermentation tank was used to prepare experimental samples, and the content values of gallic acid, glucose, caffeine, and free amino acids in coffee were measured using a spectrophotometer. The experiment of antioxidant activity and sensory evaluation of wet fermentation was carried out. Results The wet fermentation process significantly optimized various indicators of coffee, not only made the aroma more rich and long-lasting, but also achieved a perfect balance between sweetness and taste, demonstrating excellent quality of richness and delicacy, and the antioxidant properties of coffee were particularly outstanding. Conclusion This study can provide the market with higher quality coffee options.

Objective To study of the quality, safety and authenticity analysis of beef jerky in Inner Mongolia region. Methods This study used 114 beef jerky samples from 7 categories of food supervision and sampling inspection and enterprise entrusted inspection in Inner Mongolia region 2017 to 2024 as experimental samples, and used 23 national food safety standards to comprehensively analyze their nutritional components, heavy, food additives, veterinary drug residues, microorganisms, animal source and other 23 quality and safety parameters. Results The protein content and energy of 114 samples of Inner Mongolia beef jerky were (44.26±7.19) kJ/100 g and (1450.13±536.11) kJ/100 g, respectively, but the content of fat and moisture varied greatly, the fat content of Y-2 fried beef jerky and Y-5 fat and lean beefky was significantly higher than other samples, and the moisture content of Y-2 fried beef jerky was significantly lower than other samples lead (detected in 6/25 samples), chromium (detected in 22/25 samples), cadmium (detected in 2/25), nitrite (detected in 5/18 samples), benzoic acid (not in all 37 samples), sorbic acid (detected in 2/37 samples), sodium diacetate (detected in 4/37 samples), carmine (not detected in all 18 samples), sodium saccharin (not detected in all 20 samples), clenbuterol (not in all 19 samples), ractopamine (not detected in all 19 samples), salbutamol (not detected in all 10), total bacterial count (50 samples, 9 of which were less than 10 CFU/g, and 3 were greater than 10⁴ CFU/g), and coliform group (all 50 samples were <10 CFU/g) were all in compliance with the limit requirements of the National Food Safety Standards; 12 samples tested were found to be of bovine origin, and no porcine origin detected. Conclusion The beef jerky in Inner Mongolia has the characteristics of high protein and high energy, and the heavy metal, food additives, veterinary drug residues, microbial indicators all meet the national food safety standards and there is no pork adulteration, showing a high level of quality safety. The moisture and fat content vary greatly which may be related to the processing technology of frying, roasting and air-drying of Inner Mongolia beef jerky and the raw materials.