酿造酱油、配制酱油及酿造食醋、配制食醋的鉴别

乙酰丙酸是配制酱油的特有成分，在硫酸溶液中，乙酰丙酸可与香草醛反应而呈现蓝绿色。掺有尿素的酱油在与丁二酮肟、磷酸混合后，加热煮沸会呈现红色。用酱色、食盐等配制的劣质酱油可用测定氨基酸态氮和酱色含量的方法进行鉴别。酿造食醋和配制食醋的常用鉴别方法是碘液法和高锰酸钾法。     

Design of a combined ozone/electron beam process for waste water and economic feasibility of the process

A design of a combined ozone/electron beam irradiation process for treating a 50 m³/h waste water stream from a molasses processing is discussed. Moreover, a cost evaluation of such a process in comparison to a conventional ozonation/biology treatment process has been performed to assess the potential of the irradiation process for technical use. Although the result of this comparison is not bad for the irradiation process an implementation into a full scale plant would not seem to be the thing to do in the present case.     

内蒙古地区沙生植物--沙枣对亚硝酸盐分解作用的研究

利用分光光度法研究了内蒙古地区沙生植物———沙枣对亚硝酸盐的分解作用。结果表明,沙枣中富含的维生素C、维生素E和脯氨酸等抗氧化剂可以作为还原剂与亚硝酸盐作用,从而降低亚硝酸盐的含量;加入的沙枣量愈多,随时间延长对亚硝酸盐的分解能力亦增强,但不呈线性关系。试验结果表明,沙枣不仅可以作水土保持、防沙造林的先锋树种,还由于它富含抗氧化物,可作为人体降低体内亚硝胺生成的良好补充源。     

A biochemometrics strategy combining quantitative determination,bioactivity evaluation and relationship analysis for identification of analgesic alkaloids of raw and vinegar‐processed Corydalis turtschaninovii

A biochemometrics strategy combining quantitative determination, bioactivity evaluation, and relationship analysis was proposed for identification of analgesic components of herbs. First, a robust liquid chromatography tandem mass spectrometry method was developed for simultaneous determination of nine major alkaloids in crude and vinegar‐processed Corydalis turtschaninovii. Nine alkaloids were separated on a BEH C₁₈ column with a mobile phase consisting of acetonitrile and water spiked with 0.1% formic acid and then detected by multiple reactions monitoring in the positive ion mode. Nitidine chloride was employed as the internal standard. The method displayed good linearity and the precisions of intra‐day and inter‐day were all within 3.0%. The recovery rates of each alkaloid ranged from 97.1 to 102.9%. The method was successfully applied for quantitative analysis of nine alkaloids in ten batches of crude and vinegar‐processed Corydalis turtschaninovii. Second, the analgesic effects of crude and vinegar‐processed Corydalis turtschaninovii were evaluated in mice. Third, principle component analysis, canonical correlation analysis, and partial least squares regression were used to analysis the relationship between the contents of nine major alkaloids and the analgesic effect of different crude and vinegar‐processed samples. Tetrahydropalmatine, coptisine, and dehydrocorydaline have a close positive correlation with the analgesic effect.     

生物质热解制备木醋液及其性质研究

对杉木屑、棉杆、竹屑三种生物质热解制得的木醋液产率、基本理化性质及其有机成分进行了分析研究。结果表明,三种生物质原料在350℃下热解制得的粗木醋液、精制木醋液产率相差不大,相同条件下氯化钾浸渍处理后的杉木屑热解所得的粗木醋液、精制木醋液的产率有所降低。三种原料制得的精制木醋液的理化性质不同,杉木屑木醋液的pH值最小,密度最大,竹屑和棉杆木醋液的有机酸含量相对较高。采用GC-MS对精制木醋液中的有机成分进行了分析,结果表明,杉木屑木醋液中的主要组分为酸类、酚类和酮类化合物,棉杆和竹屑木醋液中的主要组分除这三类有机物质外,还含有相对含量较高的醇类化合物。酸类和酚类化合物在三种木醋液中的相对含量依次是竹屑 >棉杆 >木屑;酮类的相对含量依次是木屑 >棉杆 >竹屑。氯化钾处理后的木屑热解所得的木醋液中主要组分酚类和酮类化合物的相对含量有所降低,酸类化合物的相对含量增加,主要表现为乙酸相对含量的增加。与杉木屑木醋液相比,KCl处理后的杉木屑木醋液中的醇类化合物相对含量增加了1倍左右。     

Monitoring of substrate and product concentrations in acetic fermentation processes for onion vinegar production by NIR spectroscopy: value addition to worthless onions

Wastes and by-products of the onion-processing industry pose an increasing disposal and environmental problem and represent a loss of valuable sources of nutrients. The present study focused on the production of vinegar from worthless onions as a potential valorisation route which could provide a viable solution to multiple disposal and environmental problems, simultaneously offering the possibility of converting waste materials into a useful food-grade product and of exploiting the unique properties and health benefits of onions. This study deals specifically with the second and definitive step of the onion vinegar production process: the efficient production of vinegar from onion waste by transforming onion ethanol, previously produced by alcoholic fermentation, into acetic acid via acetic fermentation. Near-infrared spectroscopy (NIRS), coupled with multivariate calibration methods, has been used to monitor the concentrations of both substrates and products in acetic fermentation. Separate partial least squares (PLS) regression models, correlating NIR spectral data of fermentation samples with each kinetic parameter studied, were developed. Wavelength selection was also performed applying the iterative predictor weighting–PLS (IPW-PLS) method in order to only consider significant spectral features in each model development to improve the quality of the final models constructed. Biomass, substrate (ethanol) and product (acetic acid) concentration were predicted in the acetic fermentation of onion alcohol with high accuracy using IPW-PLS models with a root-mean-square error of the residuals in external prediction (RMSEP) lower than 2.5% for both ethanol and acetic acid, and an RMSEP of 6.1% for total biomass concentration (a very satisfactory result considering the relatively low precision and accuracy associated with the reference method used for determining the latter). Thus, the simple and reliable calibration models proposed in this study suggest that they could be implemented in routine applications to monitor and predict the key species involved in the acetic fermentation of onion alcohol, allowing the onion vinegar production process to be controlled in real time.     

Effect of vinegar steaming on the composition and structure of Schisandra chinensis polysaccharide and its anti-colitis activity

In this study, infrared spectroscopy, high-performance liquid chromatography, and matrix-assisted laser desorption ionization-time-of-flight-mass spectrometry (MALDI-TOF-MS) technology were applied to systematically explain the Schisandra chinensis’s polysaccharide transformation in configuration, molecular weight, monosaccharide composition, and anti-ulcerative colitis (UC) activity after vinegar processing. Scanning electron microscopic results showed that the appearance of S. chinensis polysaccharide changed significantly after steaming with vinegar. The MALDI-TOF-MS results showed that the mass spectra of raw S. chinensis polysaccharides (RSCP) were slightly lower than those of vinegar-processed S. chinensis polysaccharides (VSCP). The RSCP showed higher peaks at m/z 1350.790, 2016.796, and 2665.985, all with left-skewed distribution, and the molecular weights were concentrated in the range of 1300–3100, with no higher peak above m/z 5000. The VSCPs showed a whole band below m/z 3000, with m/z 1021.096 being the highest peak, and the intensity decreased with the increase of m/z. In addition, compared to RSCPs, VSCPs can significantly increase the content of intestinal short-chain fatty acids (SCFAs). This study showed that the apparent morphology and molecular weight of S. chinensis’s polysaccharides significantly changed after steaming with vinegar. These changes directly affect its anti-UC effect significantly, and its mechanism is closely related to improving the structure and diversity of gut microbiota and SCFA metabolism.     

离子色谱-脉冲安培检测白醋和豆腐水中单糖和大豆低聚糖

建立了测定白醋和豆腐水中常见的的3种单糖(半乳糖、葡萄糖、果糖),以及蔗糖、蜜二糖、棉子糖和水苏糖等大豆低聚糖的方法.以NaOH淋洗液梯度淋洗,7种糖在CarboPac PA10高效阴离子交换柱(HPAEC)上可以在30 min内完成分离.使用脉冲安培检测器(PAD)进行测定,7种糖的检出限(进样25 μL,S/N=3)分别为3、2、3、6、4、7和6 μg/L,且均具有较宽的线性范围(0.02～20 mg/L).白醋和豆腐水样品测定的相对标准偏差在0.15%～3.16%之间,7种糖的加标回收率在92%～104%之间; 本方法检测糖简便快捷、分离效果好、无需衍生、灵敏度高,适用于大豆及大豆制品中的常见糖组分的分析.     

Characterization and Comparison of Commercial Chinese Cereal and European Grape Vinegars Using 1H NMR Spectroscopy Combined with Multivariate Analysis

A holistic and comparative quality assessment of vinegars from different countries is needed with international trade of vinegar become frequent. In this study, compounds characterization and comparison of commercial‐grade Chinese cereal and European grape vinegars were performed using ¹H NMR spectroscopy coupled with principal component analysis (PCA) and orthogonal projection to latent structures discriminate analysis (OPLS‐DA). The results showed that Balsamic vinegars of Modena were clearly discriminated by higher amount of fructose and glucose, while Chinese aromatic vinegar and aged vinegars were characterized by higher amount of amino acids, volatile compounds, succinate and betaine. On the other hand, flavoring compounds in Chinese rice vinegar and European wine vinegars are less than the others. These characteristic components are associated with the special raw materials and producing process of each types of vinegar and endow them special flavor. The results obtained in this study provide a global insight into vinegar through a ¹H NMR based compounds analysis that allows a holistic quality assessment and comparison of vinegars from different manufacture origins.