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.

Objective To explore the effects of glnA gene on the production of curdlan by Agrobacterium. Methods A glnA gene knockout strain ΔglnA was constructed in this paper. The growth and metabolism of ΔglnA strain and the changes in yield, gel properties and infrared structure of the obtained gum were analyzed, and the expression of genes related to the synthesis of curdlan was explored by quantitative real-time polymerase chain reaction. Results The amino nitrogen consumption of the ΔglnA strain during fermentation was consistent with that of CGMCC11546. In terms of sucrose consumption, there was no significant difference before 12 h, but there was a significant difference between the ΔglnA strain and CGMCC11546 after 15 h, and sucrose consumption was significantly reduced compared to CGMCC11546. The ΔglnA strain could produce approximately 4 g/L of natural gum, which was 60% lower than CGMCC11546. Conclusion The glnA gene does not affect bacterial growth or the structure of collagen, but it can reduce the synthesis of collagen. This study provides insights into the role of glnA in curdlan production and lays a molecular biological foundation for further efforts to enhance curdlan yield.

Objective To predict and control the fermentation process of Agrobacterium sp. A02 strain to produce curdlan, establish a time-varying model to simulate bacterial growth and obtain the kinetic changes of curdlan production and sucrose consumption. Methods The viable bacteria count, sucrose content and curdlan content during the batch fermentation process of Agrobacterium sp. A02 were measured, and the experimental values were fitted using Logistic equation, Luedeking-Piret equation and Luedeking-Piret-Like equation, respectively. Results The fitting results indicated that the 3 kinds of models were applicable to the growth kinetics of bacterial cells, the generation kinetics of pectin, and the consumption kinetics of sucrose. The R² were above 0.99, and the significance level was extremely significant. The errors between the fitted and experimental values were less than 10%, indicating a good fit. Conclusion The established bacterial growth kinetics model, sucrose consumption kinetics model and curdlan production kinetics model can predict and describe the dynamic metabolic changes of Agrobacterium sp. A02 during the fermentation process, providing theoretical support for describing the fermentation kinetics characteristics and industrial production of curdlan.

Objective To explore the differences in volatile aromatic substances of Marselan wine from the eastern foot of Helan Mountain production area during the aging periods of 0, 3 and 6 months. Methods Comprehensive two-dimensional gas chromatography-time of flight mass spectrometer (GC×GC-TOF MS) was used to detect the volatile aromatic substances in the wine. Key differential volatile substances were screened according to the variable importance in projection (VIP) value and orthogonal partial least squares-discriminant analysis (OPLS-DA). Results The types of volatile aromatic substances during the wine aging period mainly included alcohols, esters, acids, phenols, etc. A total of 1286 kinds of substances were detected in the 3 aging periods. The relatively high contents of volatile aromatic substances were alcohols, esters and hydrocarbons. With the increase of the aging period, the content of esters increased from 16.9% to 27.9%, and the content of hydrocarbons increased from 13.6% to 21.5%, both showing a significant upward trend. However, the content of alcohols decreased from 53.8% to 30.3%, showing a downward trend. Taking VIP≥1.22 and P<0.01 as the indicators, a total of 21 kinds of volatile aromatic substances with important contributions to the wine in different aging periods were determined, which were 2,6,6-trimethylcyclohexadiene-1-methanol, 2-propyl-1-heptanol, heptanal, 4-tert-butylbenzyl alcohol, (S)-1-phenylethanol, diethyl methylsuccinate, isoamyl propionate, acetal, methoxyacetaldehyde, 3-chloro-1-butene, 1,8-cyclopentadeca- 1,3-diyne, β-ionone, linalool, linalyl formate, 2-furanmethanol, rose oxide, hexahydro-1,3,5-trinitro-1,3,5-triazine, 4-ethyl-5- hydroxy-3,5-dimethylfuran-2(5H)-one, 2(5H)-furanone,4,5,5-trimethyl-3-(3-methyl-2-methylidenebutyl), N-methylhexylamine, and dimethyl disulfide. Conclusion This study, by analyzing the volatile aromatic substances in Marselan wine during different aging periods, provides a theoretical basis for the control of the flavor quality during the wineaging period.

Germinated brown rice, as a functional food ingredient, is widely used in food processing. Germinated brown rice is rich in nutrients, including γ-aminobutyric acid, γ-glutamine, dietary fiber, polysaccharides, glutathione, inositol, and octacosanol, among other bioactive substances. Germinated brown rice has a variety of physiological effects, such as anti-oxidation, lowering blood lipids, lowering blood pressure, preventing diabetes, preventing and treating cancer; it also has physiological functions such as improving memory, preventing senile dementia, sobering up, regulating emotions, improving skin, and enhancing gut microbiota. The staple food products processed with germinated brown rice as raw materials include Mantou, rice, noodles, bread, biscuits, etc. They can also be processed into germinated brown rice tea, fermented drinks, brown rice wine and other drinks; it can also be processed into germinated brown rice noodles, brown rice porridge, brown rice cake, brown rice vinegar and other foods. By improving the production technology of germinated brown rice, developing distinctive germinated brown rice food, the industrialization process can be accelerated. This article reviewed the nutritional characteristics, bioactive substances, physiological functions, and application research progress of germinated brown rice in the food industry, in order to provide reference for the promotion and application of germinated brown rice.

Cichorium intybus L. is a plant with high medicinal value and wide range of uses. The roots, stems, leaves and seeds of Cichorium intybus L. are highly nutritious and have a wide range of health benefits, such as regulating blood sugar, weight loss, combating malaria and preventing cardiovascular disease. Cichorium intybus L. root is rich in inulin, a polysaccharide composed mainly of fructose units, but also contains a small amount of monosaccharides, as well as chlorogenic acid and sesquiterpene lactones and other biologically active compounds, which have the function of regulating and improving gastrointestinal function, balancing blood glucose metabolism, improving lipid metabolism, lowering blood pressure, strengthening the immune system, antioxidant, anti-fatigue effects and other functions. Cichorium intybus L. can be processed into a variety of products, such as root tea, bread, functional foods, sugar substitutes and so on. This paper summarized the nutritional composition, functional characteristics, and research progress of Cichorium intybus L. in the food industry, and proposed solutions based on the problems existing in the application of Cichorium intybus L. in the food industry, which can provide reference for the development of the Cichorium intybus L. industry.

Objective To investigate the effects of light and air on the storage quality and volatile flavor compounds of rice bran. Methods Fresh and high temperature and pressure steam stabilized rice bran were used as raw materials to investigate the effects of light and air on the changes of acid value, peroxide value, γ-oryzanol content, chromaticity and other physicochemical indexes as well as volatile flavor compounds during storage. Results During the storage process, light and air exerted insignificant influences on the acid value and γ-oryzanol content of stabilized rice bran, and had limited effects on the chromaticity indices L^*, a^* and b^* values. However, they had a significant impact on the peroxide value. For the stabilized rice bran, the peroxide value could increase by up to 25 times in the presence of light and air. As the storage time extended, the types of volatile flavor substances in rice bran samples kept increasing. The treatments of avoiding light and vacuum could effectively prevent the generation of oxidation products such as aldehydes, ketones, and alcohols. In the presence of light and air, the concentrations of aldehydes and ketones in the stabilized rice bran increased by 6 times and 26 times. Conclusion The acid value of rice bran stabilized using high temperature and high pressure steam exhibits minimal changes when exposed to light and air during storage. However, the peroxide value and its oxidation products increases substantially, this indicates that avoiding light and vacuum treatment is the key to extending the shelf life of stabilized rice bran, providing a theoretical basis for its storage and industrial application.

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 investigate the endogeneity and distribution characteristics of vanillin in different growth stages of Oryza sativa. Methods Longjing 46, Yanfeng, and Liaoxing were selected as the experimental materials. Samples were taken at different parts of Oryza sativa during its whole growth period. The vanillin content was determined by high performance liquid chromatography-tandem mass spectrometry method. Results Vanillin was present in Oryza sativa plants as early as the seedling stage. Its content in roots and leaves was 1100-1450 μg/kg and 596-972 μg/kg, respectively. During the growth process of Oryza sativa, the vanillin content in roots reached its peak at heading stage, with a content of 6560-8900 μg/kg. Subsequently, from full-heading stage to maturity stage, the vanillin content in roots gradually decreased, and at maturity stage, the content dropped to 2900-3230 μg/kg. The vanillin content in the leaves reached its peak at maturity stage. The vanillin in Oryza sativa grains started to accumulate continuously from the dough stage and reached its peak at maturity stage. In addition, at the late stage of reproductive growth, the vanillin content in the upper part of the plant (flag leaves and the upper part of the stem) was significantly higher than that in the lower part of the plant (lower leaves and the lower part of the stem), and the vanillin content in Oryza sativa husk was extremely significantly higher than that in the brown Oryza sativa. Conclusion This study confirms that vanillin has a natural background throughout the whole growth period of Oryza sativa, and vanillin is endogenously produced for the first time. Its content shows stage-specific and differential changes at different parts and growth stages. It is speculated that it may be a natural growth regulator of Oryza sativa.

Objective To establish a method for determining the volatile components of lubricating oil mixed in edible oil by headspace-gas chromatography-mass spectrometry. Methods The 1.0 g oil sample was directly taken into a 10 mL headspace bottle, then capped and sealed. Headspace-gas chromatography-mass spectrometry analysis was carried out at 90 ℃ equilibration for 20 min. Qualitative analysis was performed on 5 kinds of compounds: 4-methyl-2-pentanol, isooctanol, nonane, undecane and dodecane, while quantitative analysis was performed on isooctanol, nonane, undecane, and dodecane. Results The 4 kinds of quantitative compounds showed good linear relationships within the range of 0.5-8.0 mg/kg, and the correlation coefficients were all above 0.9980. Soybean oil was used as the sample for the spike recovery experiment. The recoveries of nonane, isooctanol, undecane, dodecane were 91.5%-98.2%, 81.9%-92.7%, 92.8%-94.6%, 89.3%-93.7% respectively and the relative standard deviations were all less than 10%. In the 5 kinds of edible oils: Soybean oil, peanut oil, rapeseed oil, corn oil and sunflower seed oil, the limits of detection of nonane, isooctanol, undecane, dodecane were 0.006-0.013 mg/kg, 0.016-0.045 mg/kg, 0.011-0.020 mg/kg, 0.020-0.036 mg/kg respectively. Conclusion This method has the advantages of simple operation and rapid detection, and does not have high requirements for the instrument, which can be carried out in general laboratories, and is suitable for the screening of trace lubricating oil contamination in edible oil.

Objective To evaluate the residual levels of tolfenpyrad and diafenthiuron in Brassica oleracea and assess the chronic dietary intake risk. Methods Brassica oleracea samples sprayed with 30% diafenthiuron·tolfenpyrad suspension concentrate were collected. The pesticide residues were detected using dispersive solid phase extraction coupled with ultra performance liquid chromatography-triple quadrupole tandem mass spectrometry. Based on the detection results, the chronic dietary intake risk was calculated using a risk probability formula, and a safety assessment was conducted. Results When 30% diafenthiuron·tolfenpyrad suspension concentrate was applied once at the maximum recommended dose of 180 g a.i./hm² with a 7-day pre-harvest interval, the residual concentrations of tolfenpyrad and diafenthiuron in Brassica oleracea were <0.01-0.39 mg/kg and 0.03-0.12 mg/kg, respectively. Both pesticide residues were below China’s maximum residue limits (MRLs) (0.5 mg/kg for tolfenpyrad and 2.0 mg/kg for diafenthiuron). Based on China’s pesticide registration and usage data, the national estimated daily intake of tolfenpyrad and diafenthiuron for the general population was 0.2215 mg and 0.0967 mg, respectively, with risk quotient of 58.6% and 51.2%, both below 100%. This indicated that the dietary intake risk was within an acceptable range. Conclusion When 30% diafenthiuron·tolfenpyrad suspension concentrate is applied at the recommended dose with a 7-day pre-harvest interval for controlling Plutella xylostella in Brassica oleracea, the pesticide residues in harvested Brassica oleracea comply with food safety standards. The long-term dietary intake risk for the general population is controllable, ensuring safe consumption.

Objective To investigate the residual characteristics of neonicotinoids pesticides in vegetables and the dietary exposure risk of residents in Hubei Province from 2022 to 2023. Methods A total of 887 vegetable samples were collected from 17 cities in Hubei Province, and neonicotinoid pesticide residues were determined. Dietary exposure was assessed according to the vegetable consumption of residents in Hubei Province. Results The overall detection rate of neonicotinoids in vegetables in Hubei Province was 33.4%, and the exceeding standard rate was 1.58%. The top 3 neonicotinoids exceeding the standard rate were clothianide (1.01%), acetamidine (0.23%) and imidacloprid (0.23%). The top 3 vegetable varieties exceeding the standard rate were fresh beans (6.06%), roots and tubers (4.48%), and melon vegetables (2.00%). The results of dietary exposure assessment showed that the chronic exposure hazard quotient of different neonicotinoids in Hubei Province was less than 1, the chronic exposure risk was low. The cumulative exposure of 8 kinds of neonicotinoids accounts for 2.78% of the acceptable daily intake of the indicator compound imidacloprid, indicating a low cumulative exposure risk. Conclusion The chronic exposure risk of neonicotinoid pesticides through vegetables for residents in Hubei Province from 2022 to 2023 is relatively low. However, there are cases of neonicotinoid pesticide residues exceeding the standard in vegetables, and the types of vegetables with excessive residues are different from those of traditional pesticides. It is suggested that relevant regulatory authorities further strengthen the supervision of neonicotinoid pesticides in fresh beans, root and tuber vegetables, and gourd vegetables.

Objective To determine the content of 8 kinds of heavy metals, copper (Cu), lead (Pb), cadmium (Cd), arsenic (As), mercury (Hg), zinc (Zn), nickel (Ni), and chromium (Cr) in Astragalus membranaceus and soil samples, and conduct the risk assessment. Methods Thirty-five batches of samples were collected in 5 provinces, namely Inner Mongolia, Shanxi, Gansu, Ningxia and Shaanxi, for the determination of 8 kinds of heavy metals in the soils of Astragalus and Astragalus origin using inductively coupled plasma mass spectrometry. The health risks of Astragalus membranaceus in different intake groups were evaluated by calculating 3 kinds of different risk assessment models, namely, the estimated daily intake, the carcinogenic risk, and the target hazard quotient. Results The recoveries were in the range of 99.1%-108.8% with the relative standard deviations in the range of 0.445%-5.720%, which indicated that the accuracy and precision of the method were good. The average heavy metal content of the 35 batches of Astragalus membranaceus was Zn>Cu>Cr>Ni>Pb>As>Cd and Hg, and no exceedance of heavy metals complied with the limit standards for heavy metals in Chinese herbal medicines in the 2020 edition of Pharmacopoeia of the People’s Republic of China. The results of the 3 kinds of risk assessments showed that the health risk of heavy metal content of Astragalus membranaceus for different groups of people was within the acceptable range. Conclusion The contamination of heavy metals in Astragalus membranaceus is widespread, and the development of the Astragalus membranaceus industry is still potentially risky. In order to ensure the medicinal safety of Astragalus membranaceus, the prevention and control of heavy metals in Astragalus membranaceus shall be carried out in the future from the planting source of Astragalus membranaceus, the processing method, and other aspects of Astragalus membranaceus.

Objective To understand the overall situation of biogenic amine content in various types of seafoods in Hainan Province, and conduct dietary risk assessment on the detected histamine. Methods A total of 387 batches of seafoods from supermarkets and farmers’ markets in 19 cities and counties of Hainan Province in 2022 were detected for 14 kinds of biogenic amines by ultra performance liquid chromatography-tandem mass spectrometry. Based on the detection results, the dietary exposure risk of the detected histamine was assessed by the hazard quotient (HQ). Results The average content of biogenic amine detected in 387 batches of seafoods were 0.101-55.248 mg/kg, and the maximum value were 2.248-10819.835 mg/kg. The higher levels of several biogenic amines were spermine, spermidine, histamine, putrescine, cadaverine and so on. And two samples detected histamine levels over 200 mg/kg. The dietary risk assessment showed that the estimated daily of histamine in different populations in Hainan Province were 0.00000-0.06690 mg·kg^-1·bw^-1·d^-1, with HQ of 0.00000-0.00134 (HQ<1). Conclusion Biogenic amines are detected in all kinds of seafoods in Hainan Province to varying degrees, but the risk of histamine exposure is low, posing a small threat to human health.

Objective To analyze the status of foodborne pathogenic bacteria contamination in meat and meat products in Yantai City, Shandong Province from 2020 to 2023, and understand the safety of related food in the city. Methods According to national food safety standard Food microbiological examination GB 4789 series standards and the requirements of Shandong food pollutants and harmful factors risk monitoring manual, 6 kinds of foodborne pathogens were detected from meat and meat products, including Salmonella, Listeria monocytogenes, Yersinia enterocolitica, Campylobacter, Diarrheagenic Escherichia coli and Staphylococcus aureus. Results The 5 kinds of foodborne pathogens and 46 positive strains were detected in 363 samples, with the total detection rate of 12.67%. The highest detection rate was Salmonella (10.48%), followed by Campylobacter (1.97%) and Staphylococcus aureus (1.33%), and no Diarrheagenic Escherichia coli was detected. Among the 4 types of samples, the highest detection rate was in raw poultry meat (26.67%) and the lowest was in cooked meat products (2.35%). The detection rate of Salmonella in prepared meat products reached 20.00%. The detection rates of pathogenic bacteria in the samples collected by farmers’ markets and online stores were relatively high (19.53%, 22.22%). Salmonella had the highest probability of causing illness in the third quarter. Conclusion Meat and meat products in Yantai City are contaminated by foodborne pathogens to various degrees, so it is necessary to focus on raw poultry meat and bulk prepared meat products, especially those originating from farmers’ markets and online stores, and it is important to strengthen the relevant circulation supervision, enhance food safety awareness and take measures to reduce the risk of cross-contamination during the sale of bulk meat products, so as to ensure food safety for consumers.

Objective To evaluate the degradation dynamics of the combined use of bifenazate and etoxazole on Vigna unguiculata and assess the dietary exposure risks for different population groups. Methods Bifenazate (sum of bifenazate and bifenazate-diazene) in samples of Vigna unguiculata collected from eight regions of China were detected by liquid chromatography-tandem mass spectrometry. Dietary exposure risk assessment was conducted based on the test results, dietary consumption data and body weight data of different population groups in China. Results The dissipation behaviors of bifenazate in Vigna unguiculata from Shandong, Anhui, Hunan and Guangxi all did not follow first-order kinetics. The dissipation behaviors of etoxazole in Vigna unguiculata from Shandong, Anhui, Hunan, and Guangxi followed first-order kinetics, and their half-lives were 1.93-2.54 d. Using a suspension concentrate containing 45% bifenazate and etoxazole with 8 mL formulation per mu (Chinese acre) to control red mites on Vigna unguiculata, spraying once, at the harvest interval of 10 d, terminal concentrations of bifenazate and etoxazole in Vigna unguiculata were <0.0100 mg/kg and <0.0020-0.0042 mg/kg, respectively. The contribution rate of the long-term dietary exposure risk of these 2 kinds of pesticides were all lower than 100% for different population groups, indicating that there was no unacceptable risk. Conclusion 45% bifenazate·etoxazole suspension concentrate is applied at a dosage of 8 mL per mu for controlling spider mites on Vigna unguiculata, with one spray application and a recommended pre-harvest interval of 10 days.

Objective To investigate and analyze the contamination of polycyclic aromatic hydrocarbon (PAHs) in 4 kinds of medicinal and edible substances, Aucklandiae radix, Citrus reticulatae pericarpium, Polygonati rhizoma, Fritillaria cirrhose bulbus in Chongqing, and assess human exposure risk from PAHs residues through ingestion of 4 kinds of substances. Methods A total of 160 samples were collected from 10 districts/counties in Chongqing. The residues of 16 kinds of PAHs were determined using gas chromatography-mass spectrometry. The contamination levels were evaluated based on the maximum residue limits of benzo[a]pyrene and PAH4 (sum of benzo[a]anthracene, chrysene, benzo[b]fluoranthene, and benzo[a]pyrene) set by the European Commission for “food supplements containing botanicals and their preparations” and “dried herbs”. The pollution characteristics of PAHs in the 4 kinds of substances were analyzed, and the sources were identified using isomer ratio analysis. Health risk assessment was conducted using the increased lifetime cancer risk (ILCR) model recommended by the US Environmental Protection Agency (USEPA). Results PAHs were detected in all Aucklandiae radix, Citrus reticulatae pericarpium, Polygonati rhizoma, Fritillaria cirrhose bulbus. The detection rate of the highly carcinogenic benzo[a]pyrene was 24%, with an exceedance rate of 1.25%, while the exceedance rate for PAH4 was 1.9%. Citrus reticulata peel exhibited the highest benzo[a]pyrene detection rate (83%), and its maximum PAH4 content reached 151.66 μg/kg, exceeding the MRL by more than threefold. PAHs in all 4 kinds of substances were predominantly low-molecular-weight 2-3 ring compounds. The ILCR values of cancer risk caused by taking 4 kinds of substances in different populations were 1.46×10^-7-7.26×10^-7, 1.21×10^-6-6.04×10^-6, 1.89×10^-7-9.38×10^-7, 6.96×10^-8-3.46×10^-7, respectively. Conclusion The 4 kinds of dual-purpose substances are contaminated with PAHs at varying levels, primarily due to biomass or coal combustion. The health risks from oral intake of Aucklandiae radix, Polygonati rhizoma, Fritillaria cirrhose bulbu are low and within acceptable limits. However, Citrus reticulatae pericarpium poses a potential health risk due to PAHs exposure, warranting further attention.

Animal derived foods are one of the important sources of nutrients for humans. During the breeding process, the rational use of steroid hormones can achieve the goals of promoting growth, weight gain and anti-inflammatory effects, but excessive abuse can lead to serious threats to food safety and consumer health. At present, the detection methods for steroid hormones mainly rely on liquid chromatography, gas chromatography and their combined techniques with mass spectrometry. They also heavily rely on large precision instruments and complex preprocessing, requiring professional laboratories and technical personnel. In recent years, with the rapid development of analytical science and technology, rapid detection technologies for various steroid hormone residues have emerged, providing solid technical support for food safety. This paper presented a comprehensive review of current rapid detection methods for steroid hormones, including electrochemistry, colorimetric methods, fluorescence/phosphorescence methods, Raman spectroscopy and lateral flow immunoassay. It analyzed the advantages and disadvantages of these methods, discussed the challenges they face, and explored their future development directions. This review served as a reference for the design of rapid detection methods for steroid hormone residues in food and provided insights and inspiration for relevant researchers.

Objective To investigate the serotype distribution and antibiotic resistance characteristics of Salmonella isolated from retail poultry and pork meat in Shanghai. Methods The 109 Salmonella strains isolates from retail chicken meat and pork meat in Shanghai in 2021—2022 were collected, and serotyped by serum agglutination method. The antibiotic susceptibility of 7 classes of 14 kinds of antibacterial drugs was determined by microbroth dilution method, and the antibiotic resistance genes were analyzed by whole genome sequencing. Results A total of 22 serotypes were identified in the 109 Salmonella strains, with the Corvallis serotype being the predominant one in retail poultry chicken meat and the London serotype being the predominant one in pork meat. The 96.3% of the isolates strains were resistant to antibiotics, with the highest resistance rates to tetracycline, ampicillin, chloromycetin, and cotrimoxazole. Multi-drug resistant isolates accounted for 61.4% of all isolates, with the highest resistance to 7 classes of 12 antibiotics. All isolates were found to harbor resistance genes, with a total of 68 resistance genes identified. Conclusion The serotype of Salmonella isolated from retail poultry and pork meat in Shanghai in 2021—2022 is complex, with a high overall level of resistance and severe multi-resistance. The isolates carry multiple resistance genes, and the drug resistance is correlated with the resistance genes they carried. Continuous monitoring of foodborne Salmonella and in-depth research on important resistance mechanisms and transmission mechanisms are of great significance for ensuring food safety and guiding clinical drug use in China.

Objective To establish an analytical method for the rapid determination of 5 kinds of peptide toxins in samples from wild mushroom poisoning incidents by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Methods The remaining mushrooms and patient urine samples were extracted by methanol, purified by 250 mg N-propyl ethylenediamine (PSA), and separated by Waters CORTECS C₁₈⁺ liquid chromatography column. The mobile phase consisted of methanol and 2 mmol/L ammonium acetate (containing 0.1% formic acid) under gradient elution. They were determined by HPLC-MS/MS. Results The 5 kinds of peptide toxins had a good linear relationship (r>0.997) at the concentration 10.0-500.0 µg/L. The limits of detection (LODs) of 5 kinds of peptide toxins in the mushroom samples were 2.0-3.0 µg/kg, the limits of quantification (LOQs) were 5.0-10.0 µg/kg. In the urine samples, the LODs of 5 kinds of peptide toxins were 0.8-1.2 µg/L, the LOQs were 2.0-4.0 µg/L. The recoveries of method were 60.1%-94.9%, and the relative standard deviations were 2.0%-17.7% (n=6). Conclusion This method is accurate and rapid, and suitable for determination of peptide toxins in residual mushroom and patient urine samples from wild mushroom poisoning incidents.

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.

As one of the famous teas in China, Pu’er tea has a high reputation at home and abroad. As one of the main active components in tea, tea polyphenols have the effects of lipid-lowering, anti-inflammatory, regulating intestinal microflora, anti-oxidation, anti-cancer, inhibiting viral infection, and anti-bacteria. It has broad application prospects in many fields such as food and medical treatment. With the in-depth development of research and the continuous discovery of new functions of tea polyphenols, it has firmly occupied an important position in contemporary human life in the 21 st century and has attracted the attention of many researchers. In this paper, systematically reviewed the content determination method of tea polyphenols in Pu’er tea and the related research on biological activity in disease prevention and improvement by consulting the relevant literatures published at home and abroad in recent years. The purpose of this review is to provide a scientific basis for the targeted research of tea polyphenols in Pu’er tea, which is conducive to the better use of tea polyphenols in Pu’er tea, so as to provide a positive reference for the innovation and development of Pu’er tea related industries in China.

Objective To establish a rapid analysis method based on solid phase extraction-high performance liquid chromatography-evaporative light scattering detection (SPE-HPLC-ELSD) for determining the γ-aminobutyric acid (GABA) content in edible enzymes from medicinal and edible homologous sources. Methods Fermented panacis quinquefolii radix liquid was selected as a representative sample. After centrifugation (8000 r/min, 10 min) and ultrasonic extraction (10 min, 25 ℃), 3 kinds of different sample pretreatment methods—non-purification, dispersive solid phase extraction purification, and hydrophilic-lipophilic balance (HLB)-based solid phase extraction purification were compared and optimized. An optimized HPLC-ELSD instrumental method was developed to achieve accurate content determination. The method was then applied to determine the GABA content in other medicinal and edible homologous enzyme products. Results GABA was determined by optimized SPE-HPLC-ELSD. GABA showed a good linear relationship (r=0.999) in the mass concentration range of 50-2000 μg/mL. The recovery rate ranged from 85.93% to 96.30%, with a repeatability relative standard deviation of 0.87% (n=6). Conclusion This method is efficient and accurate, suitable for the quantitative analysis of GABA in various medicinal and edible homologous enzymes. It also provides a new approach and reference for GABA determination in complex matrices and for detecting small molecules with strong polarity and low ultraviolet absorption.

Objective To gain a more intuitive understanding of the academic context and evolutionary trends of the ion mobility spectrometry applied in the field of food science. Methods This study took the literature from the Web of Science core database over the past 15 years as the research object, and used bibliometric analysis methods to reveal the current status, hotspots and development trends of research in this field. Results Our study had shown that the number of publications on the application of ion mobility spectrometry in food science research is constantly increasing, which involves the interdisciplinary fields such as chemistry, nutrition, biochemistry, agriculture, spectroscopy, environment and pharmacy beyond food science and technology. The number of the China’s publication was far ahead, and its institutions had great international discourse power, but the personal academic influence of Chinese authors still needs to be improved. At present, the main hotspots included the studies on different food qualities and flavors, metabolomics, volatile (organic) compounds and enrichment, optimization of instrument parameters and conditions, statistical methods, sample identification and classification, and multiple instrument combination analysis based on the application of ion mobility spectrometry. The co-occurrence, clustering and emergence analysis of the keywords further reveal the evolution process and mutation situation of research hotspots. Conclusion This study can provide theoretical basis for experts and scholars in the fields of food science and analytical chemistry to grasp the international application status and future development trends of ion mobility spectrometry.

Objective To establish an ultra performance liquid chromatography-photodiode array detector method to analysis 3 kinds of furanocoumarins in dried citrus slices. Methods The samples were ultrasonically extracted with 40 mL ethyl acetate for 40 min twice. Vortex-assisted extraction were then repeated twice using 20 mL of ethyl acetate for 10 min. The ethyl acetate extracts were combined, concentrated to dryness in a rotary evaporator at 30 °C. The determination was carried out using an Acquity UPLC HSS C₁₈ SB column (2.1mm×150 mm, 1.8 μm) with a flow rate of 0.3 mL/min, column temperature of 30 ℃, and detector wavelength of 310 nm. A gradient elution was performed with mobile phase A water and acetonitrile as mobile phase B. Results The 6’,7’-dihydroxybergamottin, epoxybergamottin and bergamottin showed good linearity within 3.00~300.00 μg/mL, 4.32-432.00 μg/mL and 4.12-412.00 μg/mL with correlation coefficients greater than 0.999. The limits of detection were 0.09-0.17 μg/g. The limits of quantitation were 0.31-0.57 μg/g. The average recoveries with 3 concentration levels were 94.4%-99.1%. The relative standard deviations were between 2.7% and 4.7% (n=6). This method could separate 3 kinds of furanocoumarins in dried citrus slices well in 25 minutes. The developed method was successfully applied to determine 3 kinds of furanocoumarins in 18 kinds of dried citrus slices and powders. The content of 6’,7’-dihydroxybergamottin was between 1.52 and 159.04 μg/g. The content of epoxybergamottin was between 49.57 and 60.09 μg/g. The content of bergamottin was between 1.49 and 248.71 μg/g. Conclusion The established method has good repeatability and high accuracy, and can be used for the 3 kinds of furanocoumarins determination in dried citrus slices.

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.

Objective To evaluate of the effects of drying methods on the quality of Astragalus membranaceus based on technique for order preference by similarity to an ideal solution analysis. Methods In this study, 6 kinds of drying methods including hot air drying (HAD), heat pump drying (HPD), carbon fiber far infrared combined heat pump drying (CFFCHPD), medium short wave infrared drying (MSWID), vacuum pulsating drying (VPD), and vacuum freeze-drying (FD) were conducted to drying experiments. The effect of the drying time, unit energy consumption, color, sensory quality and effective components of Astragalus membranaceus were evaluated by technique for order preference by similarity to an ideal solution (TOPSIS). Results The results showed that CFFCHPD had the shortest drying time and lowest energy consumption for Astragalus membranaceus, with (0.15±0.00) h and (3.41±0.03) (kW·h)/kg, respectively. The L^* of the dried sample was the highest, which could have a positive effect on maintaining the color of Astragalus membranaceus, while other treatments showed varying degrees of browning. The VPD had the highest sensory score, but there was not significant difference with other treatments. CFFCHPD had a better taste, making its freshness, sweetness and richness at a high level. At the same time, retaining the nutritional components such as astragalosides, polysaccharides and calycosin-7-glucoside in Astragalus membranaceus could achieve better quality. Correlation analysis showed that the L^* was negatively correlated with the content of astragalosides and positively correlated with the content of polysaccharides. The a^* was positively correlated with the content of astragalosides, and the content of astragalosides and polysaccharides could be indirectly judged by color. Conclusion The comprehensive ranking of CFFCHPD ranked first, indicating that CFFCHPD is a promising combined drying technology suitable for drying traditional Chinese medicinal materials. This research result provides certain data support for efficient and high-quality drying of Astragalus membranaceus.

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 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 investigate the main active components of different monthly Tetrastigma hemsleyanum Diels et Gilg (TDG) from Zhoushan City and establish the map of different monthly TDG. Methods The quality of different monthly TDG was evaluated by combining fingerprint similarity evaluation cluster analysis (CA), principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA). An InterSustainSwift C₁₈ chromatographic column (4.6 mm×250 mm, 5 μm) was used, with acetonitrile-0.1 formic acid aqueous solution as the mobile phase, gradient elution, flow rate of 0.8 mL/min, detection wavelength of 20 nm, column temperature of 30 ℃, and injection volume of 10 μL. Results The fingerprint similarity evaluation results of 12 batches of different monthly TDG showed that the similarity of different monthly TDG samples varied greatly; the 13 common were identified, and 3 common peaks were recognized; CA, PCA, and OPLS-DA analysis could all classify the 12 batches of different monthly TDG into 3 categories; and 2 differential quality markers, gallic acid and quercetin, were screened out by analyzing the variable importance in projection (VIP) values under OPLS-DA. Conclusion The high performance liquid chromatography (HPLC) fingerprint and multi-component content determination method established in this study is stable and reliable, and can provide a reference for quality control of Zhoushan TDG.

Objective To investigate the potential of Cornus officinalis extract (COE) to repair skin damage caused by ultraviolet-B (UVB) exposure and to elucidate the underlying mechanisms involved. Methods By detecting the expression of UVB induced matrix metalloproteinases (MMPs) and pro-inflammatory cytokines in human keratinocytes cells (HaCaT), the photoprotective effect of COE was evaluated, and its antioxidant enzyme activity and collagen content were assessed. After exposure of mouse hairless skin to UVB radiation, extracts were applied topically and epidermal thickness, skin water content and collagen mRNA expression were determined. Results Under UVB irradiation (354.128 mJ/cm²), 1 mg/mL COE significantly enhanced antioxidant enzyme activity and significantly reduced the expression of pro-inflammatory cytokines prostaglandin E2, interleukin-1 α, and interleukin-6; simultaneously reduced the expression of MMPs; the collagen content significantly increased, with the expression levels of type I collagen and type III collagen proteins increasing by 13% and 75%, respectively. In addition, COE could alleviate the thickening of mouse skin epidermis and loss of collagen caused by UVB radiation. Meanwhile, COE treatment reduced the content of malondialdehyde (MDA) by 69%, and increased the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) by 27% and 234%, respectively. Analysis of mRNA expression in mouse epidermis showed that treatment with COE resulted in a decrease in mRNA expression levels of Mmp1a and Mmp3, while mRNA levels of Col1a1 and Col3a1 increased. Conclusion COE can improve skin damage caused by UVB radiation. This improvement was associated with increased activity of antioxidant enzymes in cells, as well as reduced expression of pro-inflammatory cytokines and MMPs. The aim of this study is to further investigate the photoprotective potential of Cornus officinalis against UVB induced skin damage through mouse and cell models, and elucidate its potential mechanisms, providing a theoretical basis for the treatment of skin diseases caused by UVB photoaging and the development of new drugs from Cornus officinalis.

Objective To establish a method for the simultaneous detection of multiple amino acids in each part of pork by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Methods The samples were extracted by acidizing high-temperature hydrolysis, acidizing microwave hydrolysis and alkalization high-temperature hydrolysis, determined by HPLC-MS/MS, electrospray ionization in positive ion mode, multiple reaction monitoring (MRM), used formic acid solution-methanol acetonitrile (1:4, V:V) solution of formic acid as mobile phase with gradient elution. Results It was extracted by acidizing microwave hydrolysis with short time and high efficiency. The detection method had a good relationship in the linear range, r² was between 0.9905 and 0.9956, the limits of detection were 0.012-0.133 ng/mL, the limits of quantitation were 0.038-0.444 ng/mL, the average recoveries were in the range 85.58% and 98.84%, the relative standard deviations (RSDs) were 0.68%-6.71%. Conclusion The method has simple process, good repeatability and stability, and can not only be used for simultaneous detection of multiple amino acids in each part of pork to achieve the purpose of high-throughput and rapid detection, but also can effectively monitor the adulteration behavior of pork products.

Objective To use summer Baojing Huangjincha 1 straight black tea, jasmine flowers, and fresh Finger citron peel as raw materials, and the flower and fruit black tea with sweetness, fruitiness and tea flavor is made through processing. Methods In this study, the sensory evaluation of flower tea, high performance liquid chromatography and visible spectrophotometer were used to study the effects of kilning, drying, jacquard and other processes on the formation of the main taste substances and quality of black tea made from flowers and fruits. Results The taste intensity of floral-fruit-scented black tea showed significant differences (P<0.05) across various processing stages. During the scenting→drying→flower removal sequence, the taste characteristics exhibited dynamic evolution: Sourness and bitterness significantly intensified during scenting (P<0.05), while sweetness began transforming during drying and peaked at the flower removal stage. Key findings included: Tea polyphenols showed a “V”-shaped change pattern during processing, while free amino acids and soluble sugars accumulated continuously, enhancing umami and sweetness. Water extracts and flavonoids initially decreased before rebounding. Non-esterified catechins, gallic acid and caffeine decreased significantly in the final product, synergistically reducing astringency and bitterness. Total esterified catechin content decreased by 16.89% during scenting but partially recovered after drying and flower removal. Notably, gallocatechin gallate content increased remarkably by 55%, while epicatechin gallate showed an initial decrease followed by recovery. Sweetness-contributing amino acids (serine, threonine, alanine, proline and glycine) collectively increased by 9.40%, significantly enhancing tea sweetness. Total theaflavin content decreased significantly, with theaflavin-3-gallate, theaflavin-3’-gallate and theaflavin-3,3’-digallate decreasing by 25.69%, 27.28% and 6.02% respectively. Taste activity value analysis revealed decreasing trends for bitterness/astringency-related compounds including caffeine, gallic acid, ECG and catechins Conclusion In this study, the mixture of jasmine flowers and fresh fruit peel of Finger citron and the processing of Baojing Huangjincha 1 straight strip black tea in summer show that the taste of black tea made from flowers and fruits mainly showed the quality characteristics of “sweet and fruity”, and effectively improved the bitterness, astringency and sourness of summer black tea, which provided a theoretical basis for the brewing process of flower and fruit tea.

Objective To prepare sodium alginate-egg gel beads using sodium alginate and egg as carriers through calcium lactate complexation, optimize their preparation process, and conduct texture analysis. Methods The sodium alginate-egg gel beads were prepared using the cross-linking method, and based on single-factor experimental design, the effects of calcium lactate concentration, curing time, and curing temperature on the hardness of the gel beads were explored. Results Under single-factor conditions, the preparation process of the gel beads was optimized using response surface methodology. The optimal preparation conditions were: 6% calcium lactate concentration, 27 minutes of curing time, and a curing temperature of 39 ℃. Under these conditions, the prepared gel beads had the following properties: Cohesiveness of 0.6457, recovery of 0.6627, hardness of 9.9983 gf, elasticity of 1.0000, chewiness of 3.5975 gf, and water content of 84.56%. Conclusion This study prepares alginate-egg gel beads with good recovery and elasticity, and determines the optimal process for the preparation of the product. This provides theoretical support and reference for expanding the application prospects of sodium alginate-egg gel beads in the fields of biomedicine and material science.

Objective To explore the effects of different drying methods on the physicochemical characteristics and volatile aroma components of Amomum tsaoko. Methods The fresh fruit of Amomum tsaoko in Nujiang Prefecture was used as the raw material, and 6 kinds of drying methods commonly used in Nujiang Prefecture were used to dry it. The physical and chemical indexes such as color and volatile oil content of Amomum tsaoko were detected, and the volatile aroma components were analyzed by gas chromatography-mass spectrometry (GC-MS). Results The color difference and volatile oil content of Amomum tsaoko dried by different drying methods were significantly different. The L^*, a^* and b^* of Amomum tsaoko dried by air energy heat pump drying and high efficiency electric energy drying were higher, suggesting that the color of Amomum tsaoko was bright brown red and the quality was high. The volatile oil content was (1.04±0.07)-(1.29±0.07) mL/100 g. The volatile oil content of natural sun drying, air energy heat pump drying and high efficiency electric energy drying was relatively high. The composition of volatile aroma substances in Amomum tsaoko dried by different drying methods had both similarities and differences. There were 19 kinds of common substances, and the relative content of most common substances was significantly different. There were 13 kinds of main volatile aroma components (relative content≥3%), and the common components were eucalyptol, trans-nerolidol, P-propylbenzaldehyde and (Z) -citral, and their relative contents had great difference. The relative content of aldehydes and alcohols in the volatile aroma components of Amomum tsaoko was 82.75%-95.69%. The relative content of aldehydes in Amomum tsaoko obtained by biomass hot air drying was the highest, and the alcohols in other drying methods were the highest. Conclusion Therefore, different drying methods have great influence on the physical and chemical characteristics and aroma of Amomum tsaoko. The color of Amomum tsaoko is different, and the aroma and flavor of Amomum tsaoko are significantly different.

Objective To optimize the new product formulations of zero-fat oil vinegar liquid seasoning based on the quantitative descriptive analysis and consumer preference testing. Methods Quantitative descriptive analysis was used to confirm the main attributes of four zero-fat oil vinegar liquid seasonings. The consumer preferences of the overall flavor were evaluated through 9-point hedonic tests. The intensity perception of the attributes of the zero-fat oil vinegar liquid seasoning were evaluated by 5-point just-about-right (5-JAR) method. Results The Luoshenhua flavor performed best for consumer overall likings, followed by the Sichuan style spicy flavor zero-fat oil vinegar liquid seasoning. The fruity flavor and the Japanese style original flavor got the lowest acceptance scores among the four zero-fat oil vinegar liquid seasoning. According to the JAR analysis, the attributes needed to be adjusted such as the strength of the color, aroma, acidity, saltiness, and aftertaste of the Japanese original flavor and fruity flavor zero-fat oil vinegar liquid seasoning samples, and the flavor of Luoshenhua and Sichuan style spicy samples needed to be fine-tuned for individual attributes. Conclusion By utilizing quantitative descriptive analysis and consumer sensory testing, the sensory attributes of products can be combined with consumer preferences, which could effectively reflect the consumer acceptance of each attributes of the product. This provided guidance and reference for new product development and formula adjustment.