Objective To optimize the process of spray drying pomelo powder and the formula of compound pomelo tea powder. Methods This study focused on optimizing the de-bittering process of pomelo peel powder and the spray drying parameters of pomelo powder, using sensory evaluation as key indicators. Subsequently, compound pomelo tea powder was made using maltodextrin, spray-dried pomelo pulp powder, pomelo outer peel powder, anhydrous citric acid, white sugar, and jasmine tea powder as raw materials. The formulation and production process of the compound pomelo tea powder were optimized through single-factor experiments and orthogonal experiments, with dispersibility and sensory evaluation serving as the key indicators. Results The optimal de-bittering process was achieved by treating pomelo peel in a water bath at 50 ℃ for 40 minutes with the addition of 1.8% β-cyclodextrin. The spray drying parameters were optimized with an inlet temperature of 160 ℃, an outlet temperature of 60 ℃, a feed flow rate of 2 mL/min, an air velocity of 3 m³/min, and an air pressure of 0.1 MPa. The final formulation of compound pomelo tea powder included 0.6% of pomelo pulp powder, 0.2% of pomelo outer peel powder, 0.1% of jasmine tea powder, 5% of sugar, 0.05% of anhydrous citric acid, and 0.4% of maltodextrin. The optimized product demonstrated excellent dispersibility 13.19 s, a high sensory evaluation score 76.3, and an overall score of 97.45, while retaining the distinct aroma of pomelo and the flavor of jasmine tea. Conclusion This process offers a promising approach for the industrial production of high-quality compound beverages.

Objective To investigate the effects of different brewing conditions on the antioxidant activities and effective components of Taraxacum mongolicum tea soup. Methods The method used a controlled univariate design to study the extraction content of total flavonoids, total polyphenols, total polysaccharides, and total amino acids in dandelion tea under different brewing times, temperatures, tea water ratios, and water quality conditions by ultraviolet-visible spectrophotometry. The antioxidant activities of dandelion tea soup were explored using 2,2-diazine-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) cationic radical, 1,1-diphenyl-2- picrylhydrazyl (DPPH) radical and nitroso scavenging rate, and ferric ion reducing antioxidant power (FRAP) as indicators. The relationships between its antioxidant activities and the content of total flavonoids, total polyphenols, total polysaccharides, and total amino acids in the dandelion tea soup were analyzed. Results When the brewing time was 5 min, the nitroso scavenging activity was the best, expressed as the equivalent concentration of vitamin C (VC) per gram of sample was 0.3938 mg VC/g, which was significantly correlated with the contents of total polyphenols, theanines, and glutamic acids, with correlation coefficients of 0.597, 0.598 and 0.616, respectively; When the brewing temperature was 94 ℃, the iron ion reduction capacity was the strongest, at 0.1784 mg VC/g, significantly correlated with the total polysaccharide content, with a correlation coefficient of 0.529; when the tea water ratio was 1:50 (g:mL), the DPPH radical scavenging activity was the strongest, at 0.2571 mg VC/g, significantly correlated with the contents of total theanines and glutamic acids, with correlation coefficients of 0.483 and 0.497, respectively; when the brewing water was tap water, the ABTS cationic radical scavenging activity was the strongest, at 0.2072 mg VC/g, significantly correlated with the total flavonoids and total polyphenols content, with correlation coefficients of 0.417 and 0.787, respectively. In summary, different brewing conditions affected the antioxidant activities and effective components of dandelion. The antioxidant activities of Taraxacum mongolicum tea were the results of the combined effects of various active compounds, including flavonoids, polyphenols, polysaccharides and amino acids. Conclusion To ensure the optimal antioxidant effects of Taraxacum mongolicum tea, when primarily considering antioxidant activities, it is recommended that the best brewing conditions are: A brewing time of 5 min, a brewing temperature of 94 ℃, a tea-to-water ratio of 1:50 (g:mL), and using tap water for brewing.

Objective To explore the optimal conditions of different deodorization treatment methods and compare the main flavor components of oyster raw materials, oyster enzymatic hydrolysates and the products obtained through different deodorization methods. Methods Taking the Crassostrea hongkongensis enzymatic hydrolysate as the research object, the changes in flavor after deodorization of the samples were investigated by means of single-factor experiments, sensory analysis and physicochemical analysis in combination. Results The optimal conditions for activated carbon deodorization were reaction time 50 min, reaction temperature 50 °C, and the amount of activated carbon addition was 1.0%. The optimal conditions for yeast deodorization were a fermentation temperature of 40 °C and a fermentation time of 60 min, and the yeast addition amount was 1.0%. Compared with oyster raw materials, the total free amino acid content in the enzymatic hydrolysate increased, both bitter and sweet amino acids increased, while the umami amino acids decreased slightly. Compared with the enzymatic hydrolysate, the sweet amino acids of the product treated with combined deodorization increased slightly, while the bitter and umami amino acids decreased slightly. The relative content of alcohols and acids increased by 21.50%. The relative content of ketones decreased by 8.49%, and the clam flavor and oil flavor decreased. Conclusion The combined deodorization of activated carbon and yeast effectively improves the flavor of Crassostrea hongkongensis enzymatic hydrolysate, providing valuable preliminary data for the development of oyster condiments.

Objective To establish ultra performance liquid chromatography-tandem quadrupole electrostatic field orbital trap mass spectrometry (UPLC-Q-Orbitrap) and use various data analysis methods to quickly identify the chemical composition of Liubao tea. Methods A Thermo Scientific Hypersil GOLD aQ (2.1 mm×100 mm, 1.9 μm) counm was used with 0.1% formic acid-acetonitrile solution (A) and 0.1% formic acid-water solution (B) as the mobile phase in a gradient elution mode. Detection of chemical components in Liubao tea by positive and negative ion mode of electrostatic spray ion source combined with electrostatic field orbital trap detector. Based on accurate mass to charge ratio data from primary high-resolution mass spectrometry, fragment ions from secondary high-resolution mass spectrometry, Thermo Scientific mzCloud network database, Thermo Scientific high-resolution mass spectrometry database for traditional Chinese medicine components, and relevant literature reports, identify the chemical components. Results Rapid analysis was conducted on the chemical components of Liubao tea, and a total of 36 kinds of compounds were identified, included 3 kinds of amino acid compounds, 3 kinds of phenolic compounds, 16 kinds of flavonoids, 1 kinds of lignin compound, 4 kinds of alkaloids, 1 kinds of terpenoid compound, 2 kinds of coumarins, 4 kinds of organic acid compounds, and 2 kinds of other compounds. Conclusion This study apply UPLC-Q-Orbitrap database to analyze the composition of Liubao tea, which can provide scientific basis for further study on the efficacy and flavor substance basis of Liubao tea.

Objective To establish a high performance liquid chromatography-ultraviolet detector method for the determination of xylo-oligosaccharide content in food. Methods The sample size, hydrolysis time, derivatization time and purification times in the pre-treatment method were investigated. Gradient elution was compared with isocratic elution to fix the chromatographic conditions. Moreover, the detection wavelength and column temperature were obtained at the same time. Results The optimized condition was as follows: Weighing sample 2.0 g; hydrolysis time 100 min; derivation time 100 min; purification for 3 times; mobile gradient elution was employed, column temperature 30 ℃; detection wavelength 250 nm. Conclusion This method has good accuracy and sensitivity for the determination of xylo-oligosaccharides in food. This study provides data support for the development of a method for the determination of xylo-oligosaccharides in food.

Objective To establish a method for the determination of nitrite content in pickles by nitroso derivative ultra performance liquid chromatography. Methods A novel and sensitive method for the determination of nitrite content was developed. This is a nitroso derivative produced based on the interaction between nitrite and antipyrine This derivative has strong absorption in 0.02 mol/L acetate buffer solution (contains 0.1% acetic acid) at a wavelength of 345 nm the nitrite content was determined by ultra performance liquid chromatography. Results Nitrite in the linear concentration range of 0.05-5.00 mg/L was determined with a limit of detection 0.01 µg/mL. The high, medium and low concentrations were spiked. The extraction recoveries ranged from 88%-96% (n=6). The relative standard deviation was the precision ranged from 2.0%-4.5%. Conclusion The method can effectively eliminate the interference of chloride ions and other anions and pigments on this experiment. The established analytical method has good sensitivity, accuracy, precision and recovery rate, and is suitable for the detection of nitrite in pickles.

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

Objective To obtain a comparative analysis of the unqualified infant and toddler foods in the sampling inspection of national food safety supervision from 2018 to 2023. Methods The information of unqualified infant and toddler food samples sampled by the national food safety supervision from 2018 to 2023 was summarized and analyzed from the sampling quantity and product brands, unqualified rate, food categories, unqualified items and sampled areas. Results The total amount of sampling of infant and toddler food decreased in the past 4 years. The unqualified rate decreased from 0.20% (2018) to 0.02% (2022), however, the unqualified rate increased significantly since 2022. Domestic and foreign brands of infant and toddler food had certain risk of problems. Milk powder and rice flour were the main unqualified infant food categories, accounting for 30.30% and 23.23% respectively. In the unqualified items, mineral content accounted for the highest proportion, followed by vitamin content. The source of unqualified infant food was mostly concentrated in the eastern coastal areas of China, and the unqualified rate of online shop sampling was also quite high. Conclusion In recent years, the state's supervision of infant and toddler food has achieved remarkable results, but it still needs to be strengthened, while the frequency and quantity of sampling inspection should be reasonably arranged. The content of mineral and vitamin in infant food doesn't meet standards, which is an urgent problem to be solved. National market supervision departments need to strengthen follow-up supervision.

Objective To detect and analyze the content of As, Cd, Cr, Cu, Ni and Pb in different dried Lycium barbarum L. from Nuomuhong Farm, Chaidamu, and evaluate the health risk of heavy metals in Lycium barbarum L. via the dietary route to humans. Methods The content of 6 kinds of heavy metals in Lycium barbarum L. was determined by inductively coupled plasma emission spectrometer. The pollution degree of Lycium barbarum L. heavy metals was evaluated by single factor index, mean pollution index, pollution factor analysis and Nemero's composite pollution index. The target risk factor method was used to evaluate the health risk of single and complex heavy metal intake of Lycium barbarum L. Results The single pollution index of 6 kinds of heavy metals in Lycium barbarum L. in this area was less than 1, and the comprehensive pollution index was less than 0.7, and the mean pollution index of the lock-in freshness group was less than 0.1, which was uncontaminated, and the mean pollution index of the sun-dried, hot air dried, and hang-dried groups was less than 0.2, which was a slightly contaminated state, and among them, Cu, and Cd were the main contaminating factors. Through correlation and principal component analysis, the sources of heavy metal pollution in the drying process of Lycium barbarum L. were characterized by diversified and multiple pathways, and the heavy metal content of Lycium barbarum L. that had undergone lock-in freshness treatment and hang-dried treatment had a higher safety coefficient; the single or compound heavy metals ingested by the human body through the consumption of Lycium barbarum L. did not pose a health risk to either children or adults. Conclusion The pollution degree of heavy metal of Lycium barbarum L. in this region is low, and the content is in accordance with the limited requirement of Chinese Pharmacopoeia 2020, and there is a certain effect of different drying on the heavy metal content of Lycium barbarum L., and this test can provide a reference basis for the prevention and control of heavy metal pollution of Lycium barbarum L. in the drying system.

Objective To establish a method for determination the content and migration of metal elements (lead, arsenic, aluminum) in paper straws by inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical spectrometry (ICP-OES), and analyze the changes in the content and migration of 3 kinds of elements. Methods Microwave digestion and immersion in 4% acetic acid for 2 hours were used as pre-treatment conditions. The instrument was analyzed according to the selected working conditions, and a standard working curve was drawn. Three elements were subjected to spiked recovery experiments, and the recovery rate and precision were calculated. Then, the content and migration amount of 3 kinds of elements were detected in 45 samples. Results The linear range of lead and arsenic elements in the ICP-MS method was 5-50 μg/L, with correlation coefficients greater than 0.999 and limits of detection of 0.005 and 0.002 mg/kg. The spiked recovery rates were 96.1% and 104.2%, with relative standard deviations of 1.5% and 3.6%. The linear range of aluminum element in ICP-OES method was 0.5-4.0 mg/L, with a correlation coefficient greater than 0.999 and the limits of detection of 0.3 mg/kg. The spiked recovery rate was 94.0%, with a relative standard deviation of 0.2%. The aluminum content and migration amount in paper straws were relatively high, especially the aluminum content, with an average content of 148.00 mg/kg and a maximum content of 1005.00 mg/kg. The 40% of the straws had a content exceeding 100.00 mg/kg. Conclusion Based on the characteristics of lead, arsenic, and aluminum content in paper straws, this study establishes an analytical method for testing aluminum, lead, and arsenic in paper straws. Based on this method, the content and migration patterns of lead, arsenic and aluminum elements in actual use are explored, providing technical support for a deeper understanding of the safety of paper straws.