Objective To prepare of Lycium barbarum and Hordeum vulgare lozenges and study of its safety quality. Methods The wolfberry and barley were ground into powder and sifted, mixed 1:1 into Lycium barbarum and Hordeum vulgare powder, kneaded into a dough with butter, and put into a grinding tool for tablet drying. The determination of toxic and harmful microorganisms and basic nutritional indexes including moisture, ash, protein, fat and starch was carried out on Lycium barbarum and Hordeum vulgare lozenges. The sensory evaluation team will score the product for sensory evaluation. Results No toxic and harmful components were detected in the lozenges of Lycium barbarum and Hordeum vulgare, and the moisture content was about 5.84%. The ash content was about 3.34%. The protein content was about 12.34%. The fat content was about 17.01%. The starch content was about 47.35%. The finished lozenge had uniform color and no special spots, complete shape without breakage, smooth taste with slight graininess, and moderate sweetness and sourness. Conclusion In this study, the utilization rate of wolfberry was improved by combining wolfberry and highland barley into lozenges, which promote the development of highland barley industry and provide a new way for wolfberry-related products.

Objective To establish a method for the determination of advanced glycation end products (AGEs) and 5-hydroxymethylfurfural (5-HMF) in loquat fruit paste by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Methods AGEs solution was obtained by extracting loquat fruit paste with pure water and treating with ultrasonic, centrifugation, solid-phase extraction and ammonia methanol solution elution, then separated by using gradient elution with 0.1% formic acid in water and methanol as the mobile phase. The detection method employed multi-reaction monitoring with positive ion. The 5-HMF solution was obtained by extracting the fruit paste in pure water, followed a liquid-liquid extraction with ethyl acetate, solid-phase extraction and 10% methanol elution. The extracts were analyzed at 30 ℃ with 10% methanol in water as mobile phase. Results It was found that the linearity of all the targets was good in the concentration range. The limits of detection and limits of quantification of each target substance were lower than 1 [AGEs/(ng/mL); 5-HMF/(µg/mL)], which could fulfill the requirements of detecting trace substances. The relative standard deviations (RSDs) of all the substances were less than 10%, and lower than 0.6% in the range of 16 hours of sample waiting time. The recoveries of all the substances were higher than 85%. Conclusion Results indicate that the method meet the basic requirement for quantitative analysis and has good accuracy and stability, which offers a detection means of studying on quality and safety of heat-processed fruit and vegetables.

Objective To establish a method for the determination of 8 kinds of fungal toxins in rice noodles with liquid-liquid dispersion extraction and multifunctional purification by high performance liquid chromatography-tandem mass spectrometry. Methods Rice noodle samples were added with isotopic internal standards, and extracted by shaking with acetonitrile water (80:20, V:V) for 25 min. After liquid-liquid dispersion extraction, a multifunctional purification column was used for purification. The 8 kinds of target compounds were separated on HSS T3 column, with acetonitrile-water (0.1% formic acid) used as the mobile phase for gradient elution, and detected under positive and negative ionization and multiple reaction monitoring mode, determined with retention time and characteristic ion pairs, quantified with internal standard method. Results This method had a good linear relationship in detecting 8 kinds of fungal toxins within the corresponding range. The correlation coefficients (r) of the target compounds were 0.9954-0.9998. The limits of detection were 0.10-10.00 μg/kg, and the limits of quantification were 0.30-30.00 μg/kg. The average recoveries of rice noodle samples at low, middle and high standard additions were 75.8%-112.0%, and the relative standard deviations were 2.9%-5.9%. The detection and analysis of 8 kinds of fungal toxins in 21 kinds of rice noodle samples in the market showed that all the toxins were detected except HT-2. Conclusion The pretreatment of sample is simple, the method is accurate and sensitive, which can be used to determine the content of 8 kinds of fungal toxins in rice noodles.

Objective To optimize the formula and processing technology of braised pork. Methods The pork belly was cured by ultrasonic treatment for 30, 45 and 60 min and static curing as the control. The marinade uptake, production rate, drip loss rate and cooking loss rate were used as indicators to compare the effects of ultrasonic and static curing on curing efficiency and quality. The sensory characteristics of braised pork made by traditional and vacuum low-temperature slow cooking techniques were compared by measuring the moisture content, thermal processing loss and sensory scores. The formula of braised pork was optimized by using sensory scores as the index and conducting single factor and orthogonal experiments. Results Compared with static curing, different ultrasonic treatment times were beneficial to the improvement of the marinade uptake and production rate of the meat, and the cooking loss rate and drip loss rate were significantly lower than those of the static curing group. The marinade uptake was the highest after 60 min of ultrasonic treatment, and there was no significant difference in the production rate between 45 min and 60 min of ultrasonic treatment. With the extension of ultrasonic treatment time, the drip loss rate gradually increased, reaching a maximum of 6.20%, and the cooking loss rate was relatively low after 45 min and 60 min of ultrasonic treatment. Overall, ultrasonic curing for 45 min was the most effective. In terms of vacuum low-temperature slow cooking technology, the total sensory scores of 65 ℃ and 70 ℃ for 6 h and 70 ℃ for 8 h were relatively high. When the slow cooking temperature was set at 70 ℃ for 6 h, the color, aroma, taste and texture of braised pork were significantly improved. Compared with the traditional process, the cooking loss rate was significantly reduced and the moisture content was significantly increased. In terms of formula optimization, the sugar-oil-water mass ratio had the most significant effect on the sensory score, followed by spices and dark soy sauce. The optimal formula was determined as follows: 250 g of streaked pork, 30 g of sugar solution (including 15 g of white granulated sugar, 6 g of vegetable oil, and 9 g of water), 6 g of soy sauce, 5 g of Huadiao wine, 400 g of water, 2 g of anise, 0.2 g of fragrant leaves, and 1.2 g of cinnamon. Conclusion The ultrasonic assisted curing and sous-vide technology can effectively improve the quality of braised pork, and the improved formula technology makes the comprehensive sensory evaluation of braised pork the best.

Objective To detect mercury content in grain by direct injection method for mercury measurement.. Methods Direct injection method for mercury measurement was used to detect grain samples such as wheat, corn, and rice, and the limit of detection, accuracy, stability, and spiked recovery rate of the method were analyzed. Results When the sample size was 0.1 g, the limits of detection mercury in wheat, corn, and rice were 0.070, 0.075, 0.085 μg/kg, all of which were less than 0.2 μg/kg. The detection results of the quality control sample was 39.42 μg/kg, which was within the specified value range. The repeatability of mercury detection, with a relative standard deviation within 5%, met the stability requirements for mercury detection. The recovery rate of mercury spiked samples were 92.2%~101.4%. Conclusion Compared with traditional mercury analysis methods, direct injection method for mercury measurement has the advantages of simple operation steps, good repeatability, fast and accurate results, and is a recommended method for rapid detection of mercury content in grain.

Objective To establish a method for the simultaneous determination of 70 kinds of pesticide residues in vegetable wastes by QuChERS (Quick Easy Cheap Effective Rugged and Safe) and ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Methods Vegetable wastes samples were extracted and purified by QuChERS method, then the samples were detected by UPLC-MS/MS, and the electrospray ionization source was used simultaneous scanning, detected under multiple reaction monitoring mode, matrix-matched calibration curve, and quantified by external standard method. Results The 70 kinds of target pesticides exhibited great linear relationships within the concentration range of 2.0-200.0 μg/L, with linear correlation coefficients were all greater than 0.99. The average recoveries ranged from 61.7% to 109.9%, the relative standard deviations were 0.4%-9.7%, with 3 addition levels at 0.002, 0.004 and 0.020 mg/kg. The limits of detection were in the range of 0.0001 to 0.0020 mg/kg, and the limits of quantification were in the range of 0.0003-0.0060 mg/kg. Conclusion This method is easy operation, fast, accurate, and good sensitivity, which is suitable for the simultaneous detection of pesticide residues in a large number of vegetable wastes samples.

Caffeine is an important functional active substance in tea. The caffeine content in different types of tea varies, which is related to the tea raw materials and different processing techniques. Separating and extracting caffeine from tea leaves can not only obtain tea with low caffeine content, but also meet a wider range of tea drinking needs. On the other hand, it is to obtain high-purity caffeine for use in fields such as medicine and food. The extraction and separation of tea caffeine involves various new extraction methods, including chemical, physical, biological, and others. The key to efficient, high-purity separation and protection of other active substances in tea is the extraction and separation technology. Caffeine also plays an important role in the basic quality, flavor, sensory perception, and activity of tea. Different amounts of caffeine can have an impact on various systems in the human body, and moderate intake can bring beneficial effects. Its functions and applications in antibacterial, catalytic, plant biostimulant, and food packaging materials are also very extensive. This article summarized the synthesis, metabolism, content, and influencing factors of caffeine in tea, summarized the extraction and separation techniques of caffeine in recent years, and evaluated the efficiency and applicability of various methods. In addition, to explore the influence of caffeine on tea quality and its various functional activities and applications, in order to break through some drinking restrictions of tea and better develop and utilize caffeine in tea.

Objective To explore the molds contamination of oyster sauce after open-cap and deterioration, and isolate and identify the contaminating molds. Methods In this study, the 6 kinds of oyster sauce in 9 different home kitchen environments were used as research objects, and the molds in the deteriorated oyster sauce were separated by the three-point separation method, combined with morphological characteristics and ITS sequence analysis for identification. Results The molds contamination in oyster sauce in the home kitchen environment mainly were due to the dominant growth of microorganisms in the environment in the oyster sauce. A total of 35 strains of molds 16 genera, were isolated from the deteriorated oyster sauce, of which 9 strains of Penicillium, 4 strains of Talaromyces and 4 strains of Aspergillus were isolated, which accounted for 25.71%, 11.42% and 11.42% of the total number of strains isolated, respectively. Conclusion Penicillium, Talaromyces and Aspergillus are the main moulds responsible for the deterioration of open-cap oyster sauce in the home kitchen environment, which can provide a research basis for the quality and safety control of oyster sauce products in the process of use.

Objective To construct a reasonable pork quality evaluation system for pork grading and high quality and high price. Methods In this study, the common Dugong three-dimensional hybrid pigs were used as the control, and the longest back muscles of 7 kinds of pigs from Shanghai were collected for the determination of various indexes such as meat appearance, texture, nutrition and flavor substances, and 13 main evaluation indexes of pork quality in the real estate were determined. In order to further construct the grading standard of Shanghai real estate pork quality, factor analysis, cluster analysis and hierarchical analysis were applied to establish a comprehensive evaluation system. Results Through factor analysis, 7 indicators (moisture content, electrical conductivity, shear force, iron, fat, inosinic acid and aspartic acid) were identified as the main factors among the selected 13 indicators, and their variance contribution rate was as high as 83.829%. Using cluster analysis and chromatographic analysis, 3 different grades of scoring criteria were established according to 7 quality indicators obtained. Conclusion This study establishes a complete pork quality evaluation model and grading criteria in Shanghai, realizes the accurate control of pork quality in Shanghai, and also provides a reference for local pork quality evaluation.

Objective To study process and quality control of active bacteria addition in infant formula milk powder. Methods This study used infant formula base powder, premix 1, and premix 2 to mix and produce infant formula milk powder. The powder was transported by gravity from the mixer to the powder warehouse for temporary storage, and stability research was conducted through accelerated testing and the indicators for accelerated testing were based on GB 10765—2021 Food safety national standard-Infant formula. Results The results indicated that bifidobacterium animalis subsp. lactis Bb-12 should be stored and maintained activity at 2‒8 ℃ and warmed up to 16‒25 ℃ in the clean work area before using. There was no significant difference in the number of viable bacteria among samples stored inpowder warehouses for different durations. The moisture contents of milk powder were constant during the six-month accelerated storage period, while vitamin C decreased to a certain extent as the storage period prolonged. Aflatoxin M₁, Cronobacter genus, Salmonella, Staphylococcus aureus and Escherichia coli were not detected after the accelerated test of 6 months. Conclusion Stability of Bifidobacterium animalis subsp. lactis Bb-12 is studied during expand production, exposure to clean work areas, and different storage periods after filling in this study providing theoretical support for the production of dairy related products.