Latest ArticlesObjective To investigate the optimal sterilization effects of ultra-high temperature (UHT) sterilization processes on thermophilic spores in plant-based drinks, and construct a UHT moderate sterilization model. Methods The physicochemical properties of 6 types of functional plant-based drinks (FPD) were compared, to determine the main changes in physicochemical indicators and the objects of characteristic drinks. The effects of pH, viscosity and solid content on the UHT sterilization effect against thermophilic spores were investigated, and a regression model was constructed. Results The pH and viscosity significantly influenced the UHT sterilization F-value (P<0.05), while the effect of solid content was found to be relatively minor. The linear fitting coefficients of pH and viscosity for the F0 values were determined to be 208.927 (P<0.05) and 23.767 (P<0.01), respectively, while the nonlinear fitting coefficients were found to be 171.067 (P<0.05) and 0.543 (square variable value, P<0.05). These results indicate that the sterilization effectiveness weakened as the values of pH and viscosity increased. When the temperature reached 130 ℃, the significance of both parameters diminished, whereas the significance of the solid content coefficient was observed to increase, with the P decreasing to approximately 0.03. The predicted values of the models and the actual F0 values showed a generally close correlation, with fitting trends resulting in R2 values of 0.868 (linear) and 0.869 (nonlinear), indicating that the model possesses a high level of predictive performance. Conclusion The constructed UHT model can accurately fit the sterilization parameters and predict the effect according to the physicochemical properties of the plant-based drinks. This study provides essential guidance for the design of the UHT sterilization process for FPD, ultimately enhancing the nutritional and flavor quality of the drink products.
Objective To find out the characteristics of amino acid composition and the differences of nutritional value of Coix lacryma-jobi in Fujian Province. Methods Taking Coix lacryma-jobi from Nanping, Putian, Sanming, Liaoyang, Guizhou and Yunnan as experimental materials, the amino acid content of Coix lacryma-jobi was determined by acid hydrolysis method and automatic amino acid analyzer. Based on the protein model recommended by Food and Agriculture Organization of the United Nations/World Health Organization (FAO/WHO) and the egg protein standard model, score of ratio coefficients of amino acids (SRC) of Coix lacryma-jobi was calculated and compared. At the same time, the changes of amino acids in Coix lacryma-jobi in different areas before and after storage for 10 months were studied, and the mechanism of amino acid changes in Coix lacryma-jobi during storage was discussed. Results There were 17 kinds of protein amino acids in Coix lacryma-jobi in 6 areas, with the total amino acids of 7.34-17.97 g/100 g. The amino acid content of Coix lacryma-jobi in Liaoyang area was the highest, followed by Putian area Coix lacryma-jobi, while Sanming area Coix lacryma-jobi exhibited the lowest levels. After 10 months of storage, the total amino acid content of Nanping area Coix lacryma-jobi remained relatively stable. In contrast, Coix lacryma-jobi from other regions showed varying degrees of decline in total amino acids. Notably, Sanming area Coix lacryma-jobi demonstrated a significant increase in the total amino acid content from 7.34 g/100 g to 11.17 g/100 g, representing a 52.2% rise. The total essential amino acids (TEAA) in Coix lacryma-jobi ranged from 1087 to 2389 mg/g N. The essential to total amino acid ratio (E/T, 33.82%-39.29%) and essential to non-essential amino acid ratio (E/N, 51.09%-64.71%) indicated that Liaoyang area Coix lacryma-jobi had the highest TEAA, whereas Sanming area Coix lacryma-jobi had the lowest, with both falling below the egg protein reference pattern. However, Putian and Liaoyang area Coix lacryma-jobi surpassed the FAO/WHO reference standards in terms of TEAA, E/T and E/N ratios. The SRC of Coix lacryma-jobi was 39.71-48.30 from 6 origins, and the highest score was Coix lacryma-jobi in Nanping area and the lowest was Coix lacryma-jobi in Liaoyang area. Lysine was the first restrictive amino acid, followed by methionine and cystine. Conclusion Coix lacryma-jobi contains a complete range of amino acids, giving it significant development and utilization potential. This can serve as a basis for evaluating the quality of Fujian Coix lacryma-jobi.
Objective To establish a rapid determination and analysis method for crotonoside, magnoflorine and isoguanine in food by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Methods The samples were extracted with 60% (volume fraction) acetonitrile aqueous solution. After vortex oscillation, ultrasonic extraction and high-speed centrifugation, the supernatant was filtered through a filter membrane and used for determination. The mobile phase consisted of acetonitrile-0.1% (volume fraction) formic acid aqueous solution for gradient elution. Separation was carried out on a Waters BEH Amide (3.0 mm×100 mm, 2.5 μm) chromatography column. The mass spectrometry was conducted using positive ion electrospray ionization (ESI+) and multiple reaction monitoring (MRM) mode for qualitative and quantitative determination of 3 kinds of alkaloids, namely crotonoside, magnoflorine and isoguanine. Results The linear relationship between 3 kinds of alkaloids was good within the corresponding mass concentration range (r>0.997), the average recoveries ranged from 83.7% to 102.3%, and the relative standard deviations were ranged from 3.2% to 7.4% (n=6). The limits of detection for crotonoside and magnoflorine were both 0.1 μg/L, and the limits of quantification were 1.0 μg/L. The limit of detection for isoguanine was 1.0 μg/L, and the limit of quantification was 2.0 μg/L. Conclusion This method has a rapid and simple sample pretreatment process, short time-consuming, high sensitivity and good accuracy, and is suitable for the rapid detection and confirmatory analysis of 3 kinds of alkaloids in emergency incidents of suspected croton poisoning.
Objective To discuss the nutritional quality and flavor characteristics of honey from Apis cerana cerana in Changbai Mountain. Methods The physicochemical and nutritional parameters (diastase number, fructose, glucose, maltose, sucrose, fat, protein, proline, Na and vitamin C) of honey from Apis cerana cerana in Changbai Mountain (region of Tonghua, Jilin, Baishan and Yanbian) were determined based on several published standards in this study. The volatile compounds in honey were detected by gas chromatography-ion mobility spectrometry (GC-IMS), and its aroma characteristics were clarified. Results The results showed that all the indicators were in line with the national and industrial standards, and the quality of honey from Tonghua region was the best. A total of 105 compounds were identified in honey from 4 region, among which alcohols, aldehydes, ketones and esters were important components of the flavor. And there were differences in the volatile components of honey from Changbai Mountain in different regions. Among them linalool oxide, furfural, ethyl acetate, acetic acid, 2-methyl-1-propanol and 3-methyl-1-butanol were the characteristic substances of honey from Apis cerana cerana in Changbai Mountain, and they contributed to the composition of its characteristic aroma. Conclusion Honey from Apis cerana cerana in Changbai Mountain is a nutritious honey food with certain advantages in nutritional values such as proline, protein, and vitamin C.
Objective To study the optimization of convenient mixed grain rice process through response surface methodology. Methods Using purple rice, black rice, oatmeal rice and red rice as the main raw materials, the pregelatinization process was determined by the water absorption and pasting degree of the miscellaneous grains. To optimize the production process of convenient omnivorous rice through single-factor and response surface tests using sensory evaluation as an index. Results The result showed that the pregelatinization process of mixed grains was soaking at 23 ℃ for 120 min and steaming for 20 min; the suitable parameters of the process for the convenient mixed grain rice were 27% of mixed grain rice addition, 54 min of cooking time, and 1:1.30 of rice-water ratio. This time, it was possible to produce a convenient mixed grain rice with superior flavor, tissue state, texture and color. Conclusion In this study, a convenient and flavorful rice of convenient mixed grains was developed. This provides a certain theoretical basis for pre-cooking treatment in the processing of mixed grain rice and promotes the industrialization of mixed grain food.
Objective To optimize the brewing process of Grossedentata tea flavored beer and evaluate its effect on reducing uric acid. Methods With Grossedentata tea and malt as the main raw materials, the brewing process of Grossedentata tea flavored beer was optimized through single-factor experiments and response surface optimization experiments. Meanwhile, the physical and chemical indicators of Grossedentata tea flavored beer, such as alcohol content, diacetyl, total phenols, and total flavonoids, were determined. A high-uric-acid mouse model was established through animal experiments to detect the uric acid levels and liver function and other biochemical levels of mice after consuming Grossedentata tea flavored beer and ordinary beer, and to evaluate the uric acid-lowering effect of Grossedentata tea flavored beer. Results The optimal brewing process of Grossedentata tea flavored beer was 10 g/L of Grossedentata tea powder, 28% of malt addition, and 4% of yeast addition. Under these conditions, the alcohol content of this beer was 1.57%vol, the diacetyl content was 0.08 mg/L, the total phenol content was 12.41 mg/mL, the total flavonoid content was 86.12 μg/mL, the pH was 4.4, and the sugar content was 7°Brix. Animal experiments indicated that compared with ordinary beer, Grossedentata tea flavored beer could reduce serum uric acid, hepatic xanthine oxidase activity, and hepatic malondialdehyde levels. Compared with the positive control group, the activity retention of hepatic superoxide dismutase and catalase was higher, and it could reduce the content of pro-inflammatory factors, restore the level of anti-inflammatory factors, and had less side effects on the liver than the positive control group. Conclusion Grossedentata tea flavored beer has a clear and bright color, harmonious aroma, rich foam, delicate taste, and a tea aroma aftertaste. The overall sensory experience conforms to the public taste and has the health care effect of reducing uric acid.
Objective To establish 2 kinds of methods for the determination of 17-pentatriacontene in honey by gas chromatography-flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS). Methods After dissolved in water, the sample was extracted with petroleum ether, purified on a florisil cartridge, separated by DB-5MS column (15 m×0.25 mm, 0.25 μm), and determined by GC-FID and GC-MS, then quantified by external standard method. Results The GC-FID and GC-MS were quantified using matrix-free standard curve and matrix-matched standard curve respectively, with limits of quantification of 1.0 mg/kg and 0.5 mg/kg, linear ranges of 1-100 mg/kg and 0.5-40.0 mg/kg, and recovery rates ranging from 88.9% to 94.5% and from 91.2% to 98.2%, respectively. The relative standard deviations were 4.0%-6.4% and 4.6%-7.3%, respectively. The results of the 2 kinds of methods were basically consistent, with a relative deviation of no more than 2.4%. The proposed methods were applied to 158 honey samples of Apis cerana honey and Apis mellifera honey, 17-pentatriacontene was only detected in Apis cerana honey, with a content range of 0.58-51.10 mg/kg. Conclusion The accuracy and precision of the GC-FID and GC-MS methods established in this study are both good, and the 2 kinds of methods can be applied to the determination of 17-pentatriacontene in honey. The results of real sample tested indicate that 17-pentatriacontene can be used as a characteristic marker for Apis cerana honey.
Objective To investigate the quality differences between Actinidia chinensis Planch in China’s main production areas and New Zealand Actinidia chinensis Planch, and make a comprehensive evaluation. Methods This study used Actinidia chinensis Planch fruits from the main production areas of China and New Zealand Actinidia chinensis as experimental materials, analyzed the phenotypic traits, nutritional composition and sensory evaluation indexes of Actinidia chinensis Planch fruits, and analyzed and comprehensively evaluated the Actinidia chinensis Planch fruits by using the method of systematic description, entropy weight-technique for order preference by similarity to ideal solution (TOPSIS) method was used to analyze and comprehensively evaluate Actinidia chinensis Planch. Results The quality indexes of Actinidia chinensis Planch fruits from different production areas differed significantly. The soluble solid content of red Actinidia chinensis Planch was the highest in Yunnan and Shaanxi, with 15.9 and 15.5%, respectively, and the lowest total acid content in Sichuan was0.86%, and the mean value of soluble sugar content was the highest in Yunnan and Sichuan, with 62.2% and 59.5%, respectively, Yunnan also had the highest mean fructose and glucose content (15.1% and 17.7%, respectively). The vitamin C content of greenheart Actinidia chinensis Planch was significantly higher than that of New Zealand for the Chinese production area; Hunan had the highest soluble solids content (18.0%), and the highest mean solid-acid ratios were found in Hunan (14.5) and Chongqing (14.4), the highest mean value of soluble sugar content was found in Chongqing (58.2%), but New Zealand had the highest mean values for fructose and glucose content, which were 14.2% and 16.4%, respectively. The yellow heart Actinidia chinensis Planch had the highest mean values of vitamin C, soluble solids, solid-acid ratio, soluble sugars, fructose and glucose content for New Zealand (0.89 mg/g, 16.7%, 14.3, 63.6%, 15.6% and 17.7%, respectively), but the sucrose content of Sichuan (3.73%) and Henan (3.61%) was higher than that of New Zealand. Conclusion The study show that there are quality differences between Actinidia chinensis Planch from China’s main production areas and New Zealand Actinidia chinensis Planch. The entropy weight-TOPSIS model show that the top two scores of red Actinidia chinensis Planch are the Hongyang Actinidia chinensis Planch from Yunnan and Sichuan, the top score of green Actinidia chinensis Planch is the CuiXiang Actinidia chinensis Planch from Shaanxi, and the Hayward Actinidia chinensis Planch from New Zealand ranked the 4th, while the top score of yellow Actinidia chinensis Planch is the Sunshine Golden Fruit Actinidia chinensis Planch from New Zealand, follow by the G3 Actinidia chinensis Planch from Sichuan and Yunnan. This study verify the validity of the multi-indicator evaluation through the three-dimensional correlation model of “sensory-composition-phenotype”, and provid methodological support for the construction of the Actinidia chinensis Planch quality evaluation system.
Objective To achieve the identification and rapid detection of commonly found types of meat floss on the market via low-field nuclear magnetic resonance. Methods This study developed a low-field nuclear magnetic resonance two-dimensional relaxation fingerprinting technique suitable for the rapid detection of meat floss product types. Based on the colour discrepancy, different types of meat floss products can be distinguished. Results The developed two-dimensional relaxation fingerprinting technique can quickly and non-destructively distinguish between commonly available pork, chicken, beef, fish, and their mixed meat floss products.With the change in the proportion of different components in meat floss, the fingerprint spectrum shows a significant qualitative trend, effectively reflecting the changes in the proportion of various meats in meat floss, which proves the accuracy of this technology. Conclusion This research method can rapidly, non-destructively and accurately differentiate most types of meat floss on the market, meeting the needs of the food industry and government testing institutions, making it a promising new detection tool with great potential.
Objective To use coleslaw at the retail-to-consumption level as a source of contamination with Staphylococcus aureus, assess the health risk posed to residents of Jilin Province and identify the key contributing factors. Methods Based on the monitoring data of Staphylococcus aureus in coleslaw in Jilin Province from 2011 to 2019, combined with the data of residents’ coleslaw consumption and temperature, a prediction model of Staphylococcus aureus growth was established. The results were analysed and Monte Carlo simulated using @Risk8.0 software, and a quantitative risk assessment of Staphylococcus aureus in commercially available coleslaw in Jilin Province was carried out in 4 parts: Hazard identification, exposure assessment, hazard characterization and risk analysis. Results The data statistics showed that the initial contamination rate of Staphylococcus aureus in coleslaw was 3%, and the average contamination was -2.37 log10CFU/g, with a 95% confidence interval of (-5.88, 1.27) log10CFU/g. The assessment results showed that the probability of triggering Staphylococcus aureus intoxication was 0.1%, and the number of cases of illness that could be caused by Staphylococcus aureus was 154500 cases per year. Conclusion The initial level of Staphylococcus aureus contamination in coleslaw is most important in causing the risk of Staphylococcus aureus infection, follow by storage temperature. Keeping the source ingredients, preparation environment clean and hygienic, and having good refrigerator use habits are important measures to reduce the risk of developing Staphylococcus aureus infections in coleslaw.