Objective To compare the similarities and differences in the identification results of Staphylococcus aureus in dried fruits analyzed by 3 experimental methods: Biochemical identification, mass spectrometer identification and molecular biological identification. Methods Staphylococcus aureus in dried fruits was isolated. The isolated typical strains were identified and compared through 3 approaches: Biochemistry (VITEK 2-Compact) mass spectrometer (VITEK MS), and molecular biology (real-time fluorescence quantitative polymerase chain reaction), the identification results of the 3 types of experiments were compared. Results All 3 identification methods could identify Staphylococcus aureus to the species level, but there were certain differences in efficiency and time required. Mass spectrometry yielded more accurate results with higher timeliness. Conclusion This paper analyzes the advantages and disadvantages of different identification methods, combines traditional methods with modern technologies. The enrichment and isolation in traditional detection methods provide a basis for subsequent identification. On this basis, advanced identification technologies with different principles are integrated to form a complete detection process. This combined mode can mutually verify the results, improve the detection accuracy, and provide new ideas for establishing a more reliable microbiological detection system for characteristic dried fruits.

Objective To analyze the food safety situation of edible oils, fats, and their products in China from 2019 to 2023. Methods Sampling results of edible oils, fats, and their products from the national safety supervision from 2019 to 2023 were summarized, and their overall, unqualified items and other information were analyzed. Results The results showed that the overall unqualified rate of edible oils, fats and their products showed a downward trend from 2019 to 2023; unqualified products were mainly produced in Xinjiang, Jilin, Anhui, Hubei, Inner Mongolia, Jiangxi and other regions; rapeseed oil, peanut oil, sesame oil, and soybean oil were the main unqualified edible oil varieties in the sampling inspection from 2019 to 2023; the detected unqualified items mainly include benzo [a] pyrene, acid value (calculated as KOH), peroxide value, and solvent residue. Conclusion The governments and relevant departments in Xinjiang, Jilin, Anhui and other provinces with high disqualification rates shall strengthen source control, promote large-scale planting and standardized storage, upgrade production technology and supervision, strengthen sampling inspection and traceability mechanism, strengthen market supervision on production, processing and transportation, and improve the traceability system of edible oil, fat and its products, strictly follow the production process standards, store reasonably, and improve the quality of edible oil; strengthen the sampling inspection of products with high unqualified rates, such as rapeseed oil, peanut oil, sesame oil, soybean oil, etc.

Objective To understand the quality of Triticum aestivum L. in Henan Province from 2020 to 2024. Methods A comparative analysis was conducted on the quality data of Triticum aestivum L. in Henan Province from 2020 to 2024. Results The quality of Triticum aestivum L. in Henan Province showed a fluctuating upward trend from 2020 to 2024. Due to weather conditions, the Triticum aestivum L. quality in 2023 was the worst, with an average test weight of 755 g/L. The proportion of third grade or above (including third grade) was 64.4%, and the average of defected kernel was as high as 34.6%. The overall quality of Triticum aestivum L. in 2022 was the best, with an average test weight of 801 g/L. The proportion of third grade or above (including third grade) was 99.6%, and the average of defected kernel was 2.9%. Through the analysis of Triticum aestivum L. quality over the past 5 years, it was found that Triticum aestivum L. in Henan Province was mainly composed of medium gluten varieties, strong gluten varieties had been effectively promoted throughout the province, and weak gluten Triticum aestivum L. had been well promoted in some areas of Southern Henan. Henan Province had a wide variety of Triticum aestivum L. planting varieties, and the number of Triticum aestivum L. varieties had been increasing year by year in the past 5 years. Conclusion The quality of Triticum aestivum L. in Henan Province is relatively good, mainly consisting of medium gluten varieties, which are suitable for the processing of various flour products. But there are problems such as a wide variety of varieties and a low proportion of large-scale planting.

Objective To investigate the effects of enzymatic hydrolysis combined with ultrasonication extraction conditions on the yield, antioxidant and hypoglycemic activities of Mori fructus polysaccharides. Methods Using Mori fructus pomace as the raw material and the yield of Mori fructus polysaccharide as the index, the extraction conditions was optimized through single-factor experiments. Then the 1,1-diphenyl-2-picrylhydrazine (DPPH) radical scavenging capacity, 2,2’-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS⁺) radical scavenging capacity, and the inhibitory effects on α-amylase and α-glucosidase activity of hot water extracting polysaccharide (HWP), enzyme-assisted extracting polysaccharide (EWP), ultrasound-assisted extracting polysaccharide (UWP), enzymatic hydrolysis combined with ultrasonication extracting polysaccharide (EUP) were investigated. Results The optimal conditions for polysaccharide extraction by enzymatic hydrolysis combined with ultrasonication was obtained. Mori fructus pomace powder was mixed with water at ratio of 1:80 (g:mL), and 2.0% composite enzyme (cellulase and pectinase at a ratio of 1:1, V:V) was added in the mixture which was maintained at 50 ℃ for 2 h with stirring. Then the mixture was treated by ultrasonication at 400 W and 60 ℃ for 50 min, and the final yield of EUP was 4.81%, increased by 7.6%, 17.5% and 21.6% compared with HWP, EWP and UWP. EUP also exhibited an improvement in the scavenging activity of both ABTS⁺ radical and DPPH radical. Compared with HWP, EWP and UWP, the semi-inhibitory concentration (IC₅₀) of α-amylase activity of EUP was 1.18 mg/mL, reduced by 40.1%, 18.6% and 30.6%, respectively, and the IC₅₀ of α-glucosidase activity of EUP was 0.31 mg/mL, reduced by 16.8%, 8.0% and 39.4%, respectively. Conclusion The enzymatic hydrolysis combined with ultrasonication extraction can not only improve the Mori fructus polysaccharide yield, but also enhance the antioxidant power and hypoglycemic activity of Mori fructus polysaccharide, which has a potential application prospect in the industry.

Objective To explore the antioxidant activity and stability of peptides from the visceral of Todarodes pacificus. Methods Free radical scavenging capacities of peptides from the visceral of Todarodes pacificus were determined, while the effects of temperature, pH and gastrointestinal digestion on the antioxidant activity of peptides from the visceral of Todarodes pacificus were also evaluated. Results The peptides from the visceral of Todarodes pacificus exhibited excellent free radical scavenging abilities, with half maximal inhibition concentration (IC₅₀) values of 1.38, 15.26, 0.90 and 2.21 mg/mL for scavenging 1,1-diphenyl-2-picrylhydrazyl radical (DPPH), 2,2’-azino-bis(3- ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) cationic radicals, hydroxyl radicals, and superoxide anion radicals, respectively. The antioxidant activity of the peptides remained relatively stable within a temperature range of 25-100 °C. Under pH conditions of 7.0-8.0, their antioxidant activity showed no significant change (P>0.05), but it significantly decreased under strongly acidic or alkaline conditions (P<0.05). After in vitro simulated gastrointestinal digestion, the peptides still maintained strong antioxidant activity. Conclusion The peptides from the visceral of Todarodes pacificus has good antioxidant activity and stability, but it shall be noted that the processing and storage of its related products avoid the influence of high temperature and extreme acid-base conditions. The present research will open up new ways for the high-value utilization of the visceral of Todarodes pacificus resources and provide scientific guidance for the innovative development of natural antioxidant peptides.

Objective To evaluate the nutritional value of amino acid content in Dendrobium devonianum Paxt. from different sources in Yunnan Province. Methods The amino acid analyzer method was used to determine the amino acid content of Dendrobium devonianum Paxt., and the amino acid nutritional value was evaluated by multivariate statistical analysis methods. Results The total amino acid (TAA) content in 29 samples ranged from 42.00 to 125.40 mg/g; the essential amino acid (EAA) content ranged from 16.80 to 44.60 mg/g; the content of aspartic acid, glutamic acid, leucine and arginine were the most abundant, which were 11.18, 9.97, 6.91 and 5.52 mg/g respectively and could be used as the characteristic amino acids of Dendrobium devonianum Paxt.. The content of cystine (0.92 mg/g) and methionine (1.10 mg/g) were the first and second limiting amino acids respectively. According to the amino acid pattern spectrum standards of the Food and Agriculture Organization of the United Nations/World Health Organization (FAO/WHO), the nutritional value of Dendrobium devonianum Paxt. cultivated in greenhouse substrates in Lianghe Area [EAA/non-essential amino acid (NEAA) was 62.69%-77.21%; EAA/TAA was 38.63%-43.55%] and wild varieties (EAA/NEAA was 61.59%-65.43%; EAA/TAA was 38.12%-39.56%) were the highest and more in line with human needs. According to the comprehensive score ranking in the quality evaluation model, the values of the samples from Mangshi M10, M1, M7 and Longling L4, L5 were higher. Two principal components were extracted by principal component analysis, and the cumulative contribution degree was 83.852%, and a quality evaluation model of Dendrobium devonianum Paxt. was established. Cluster analysis was carried out with amino acids and comprehensive scores as variables respectively, and all samples could be divided into 3 major categories. Conclusion The amino acids of Dendrobium devonianum Paxt. is rich in nutrients, and the amino acid content of Dendrobium devonianum Paxt. from different sources varies. This study provides an important theoretical basis for the development and utilization of the nutritional value of Dendrobium devonianum Paxt.. At the same time, it is recommended to pay attention to the origin and cultivation methods of Dendrobium to enhance its market value.

Objective To investigate the efficacy of throat lozenge concentrate in promoting the resolution of bacterial inflammation. Methods Danio rerio model of lipopolysaccharide-induced bacterial inflammation was employed. In order to analyze the efficacy in bacterial inflammation resolution, the transgenic Danio rerio at 3-day post-fertilization was randomly selected for setting a normal control group, a model experimental group, a positive control group and throat lozenge concentrate (at the mass concentrations of 62.5, 125.0 and 250.0 μg/mL) dosage groups. Results Throat lozenge concentrate was found to reduce the amount of neutrophils, decrease the fluorescence intensity of macrophages, lower the nitric oxide fluorescence intensity at the inflammatory site, and downregulate the relative expression levels of cox2, myd88, erk2, nf-κb and tnf-α genes, while upregulating the relative expression level of the iκb-α gene. At a low mass concentration (62.5 µg/mL), the relative expression levels of inos and il-1β genes could be downregulated Conclusion The throat lozenge concentrate demonstrates efficacy in promoting the resolution of bacterial inflammation, thereby providing a scientific basis for its application in product development.

Postbiotics refer to microecological preparations made from inactivated microbial cells (dead bacterial bodies), cell lysates and fermentation metabolites, which are beneficial to the health of the host. They have attracted much attention in the fields of food and medicine due to their various biological functions such as improving intestinal health, antibacterial, anticancer and immune enhancement. The preparation of postbiotics mainly includes several steps such as fermentation, inactivation and bacterial cell disruption. The choice of fermentation strains and different inactivation methods can affect the activity of postbiotics. The active substances in postbiotics mainly include teichoic acid, proteins, peptides, short-chain fatty acids, exopolysaccharides, organic acids, etc. This paper summarized the definition, preparation methods, main components and active functions of postbiotics in combination with the research progress at home and abroad. It focused on elucidating the latest research results of postbiotics in maintaining intestinal health, enhancing immune function, and maintaining oral health, and reviewed the application progress of postbiotics in the fields of drugs, food and food preservation. At the same time, it analyzed the challenges of postbiotics in the application of the health industry from aspects such as production, product standardization, and regulatory and evaluation systems. This review aims to provide references for the development of postbiotics-related functional products and for innovation in research and application in the field of human health.

Objective To investigate the effects of varying heat treatment conditions on the texture profile and volatile/non-volatile flavor compound dynamics in fermented milk produced by Lacticaseibacillus paracasei K56. Methods Fermented milk produced by Lacticaseibacillus paracasei K56 was subjected to heat treatment at temperatures ranging from 80 to 121 ℃. The texture, volatile flavor compounds and non-volatile flavor compounds were analyzed using a texture analyzer, headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS), and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Results Under heat treatment conditions ranging from 80 to 110 ℃, the hardness of fermented milk produced by Lacticaseibacillus paracasei K56 decreased, while cohesiveness, and springiness increased. The optimal textural properties, particularly in terms of cohesiveness and gumminess, were achieved at 110 ℃ for 4 s, exhibiting a hardness of 6.2 g, cohesiveness of 0.18, springiness of 0.708 mm, and gumminess of 4.8 g. The 59 kinds of volatile flavor compounds were detected following heat treatment, with the 90-121 ℃ range significantly enhancing the levels of ketones and alcohols. Odor activity value (OAV) analysis identified esters, ketones and organic acids as the dominant flavor contributors in the fermented milk, with δ-decalactone and isoamyl acetate serving as the key odorants. Among the 652 kinds of non-volatile metabolites analyzed, the heat treatment groups 90 ℃, 15 min and 110 ℃, 4 s, 100 ℃, 15 min and 115 ℃, 4 s exhibited overlapping metabolites. Comparative analysis revealed 12 significantly differentiated indole compounds among the control group and 6 heat-treated samples. Conclusion The textural properties and flavor compounds of fermented milk produced by Lacticaseibacillus paracasei K56 vary significantly under different heat treatments. The treatment at 110 ℃ for 4 s achieves optimal results, enhancing texture and increasing flavor diversity. These findings provide a critical scientific basis for quality enhancement in fermented dairy products.

Objective To screen lactic acid bacteria from Viili fermented milk and explore the proportion of bacteria in the compound starter cultures. Methods Lactic acid bacteria were isolated using streak plating, and their taxonomic classification was determined through phylogenetic analysis based on 16S rRNA sequences. The composition of strain ratios in mixed cultures was designed with reference to the bacterial abundance observed in Viili fermented milk. Comprehensive analyses were performed to evaluate the acidity, exopolysaccharide production, textural properties and volatile flavor compounds of the mixed fermentation groups. Results Diversity analysis identified 4 bacterial genera, among which Lactococcus, Streptococcus and Leuconostoc were the dominant genera, comprising 49.12%, 40.67% and 10.21% of the total bacterial composition, respectively. Lactococcus lactis H2, Streptococcus thermophilus H17, Leuconostoc mesenteroides H30 and Lactobacillus paracasei H33 were isolated and screened. A total of 20 fermentation trials with different strain compositions were designed to conduct a comprehensive assessment of key parameters, including pH, coagulation time, textural properties, exopolysaccharide content and flavor profile. The results indicated that formulations S13 (H2:H17:H30:H33=11:4:4:1) and S17 (H2:H17:H30:H33=30:35:16:19) demonstrated the highest similarity to Viili fermented milk in terms of physicochemical and sensory properties. Conclusion The blended formulations S13 (H2:H17:H30:H33=11:4:4:1) and S17 (H2:H17:H30:H33=30:35:16:19) exhibit promising potential as compound starter cultures. This study provides a theoretical basis for developing compound starter cultures in Viili fermented milk production.