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SUMMARY: In view that enzymatic extrusion can change the degradation degree of raw materials, this paper studied the regulation rules of four indexes of degradation degree of enzymatically extruded glutinous rice flour and the correlation between these indexes and the quality indexes of brewed Chinese rice wine. The results showed that at appropriate water content, dextrose equivalent (DE) and water solubility index (WSI) were linearly related to the enzyme content in extrusion with thermostable α‐amylase (TS‐αA) and mesophilic α‐amylase (MS‐αA), respectively. But water absorption index (WAI) was not significantly affected by enzyme content. The percentages of each degree of polymerisation (DP) (1–7) and that of the sum of the rest DPs called other DP were the fundamental reasons for different DE values, WSI, WAI and quality indexes of Chinese rice wine. DP1 was significantly positively correlated with alcohol degree, and negatively correlated with total acid. DP2–DP7 (except DP4) was significantly positively correlated with amino acid nitrogen. Besides, other DP was significantly positively correlated with total sugar and total acid. The percentages of DP1, DP2–DP7 and other DP could be respectively adjusted by changing enzyme content in extrusion with MS‐αA, MS‐αA/TS‐αA and TS‐αA to control the related quality indexes of Chinese rice wine. [ABSTRACT FROM AUTHOR]

As a traditional alcoholic beverage, Chinese rice wine (CRW) with high nutritional value and unique flavor has been popular in China for thousands of years. Although traditional production methods had been used without change for centuries, numerous technological innovations in the last decades have greatly impacted on the CRW industry. However, reviews related to the technology research progress in this field are relatively few. This article aimed at providing a brief summary of the recent developments in the new brewing technologies for making CRW. Based on the comparison between the conventional methods and the innovative technologies of CRW brewing, three principal aspects were summarized and sorted, including the innovation of raw material pretreatment, the optimization of fermentation and the reform of sterilization technology. Furthermore, by comparing the advantages and disadvantages of these methods, various issues are addressed related to the prospect of the CRW industry. [ABSTRACT FROM AUTHOR]

Ethyl carbamate (EC), which has been confirmed as probably carcinogenic to humans, can be formed during the alcoholic fermentation of Chinese rice wine. In this study, EC and two possible precursors (urea and arginine) were analysed in wines fermented from rice processed by enzymatic extrusion liquefaction pretreatment, with different wheat Qu content gradients from 6 to 18% (dry basis, d.b.). The EC concentration decreased 22.5% with the addition of wheat Qu reduced to 6% for the enzymatic extrusion-processed rice wine (EE). Moreover, although the arginine was generated 6.33-8.39 times higher in the enzymatic extruded rice, instead of the traditional treated rice at the same wheat Qu level, the corresponding level of urea formed from arginine was not high in the EE. In addition, rice treated by extrusion combined with enzymatic hydrolysis was found to be more utilizable and fermentable, and the lost quality of the final traditional rice wine with the low wheat Qu level (6-14%) could be improved using enzymatically extruded rice as the fermenting material. Therefore, it may be feasible to inhibit EC accumulation in Chinese rice wine by wheat Qu control, combined with enzymatic extrusion pretreatment for rice. Copyright © 2015 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

The effect of simultaneous extrusion and enzymatic hydrolysis on the phenolics and antioxidant activities of glutinous rice and further fermented Chinese rice wine was investigated. Great modification on rice properties (water absorption/solubility index) related to higher total phenolic content (TPC) retention (87.73%) was determined in enzymatically extruded rice compared to traditionally cooked or extruded rice (37.61–50.85% TPC retention). A total of ten phenolic acids (in free/bound forms) with great loss rates were identified in different treated rice, except the enzymatically extruded rice showing effective inhibition of phenolics loss (only 2.66, 2.04, 22.49, 1.89 and 6.37% loss for total gallic, chlorogenic, vanillic, syringic, and ferulic acids, respectively). After fermentation, the level of p -hydroxybenzoic and p -coumaric acids increased predominantly, while chlorogenic acid dramatically decreased to an extremely low level, indicating a changed chemical proportion of phenolics in Chinese rice wine. Compared with raw rice, enzymatically extruded rice achieved a higher antioxidant activity (DPPH, ABTS, reducing capacity and FRAP), probably due to the synergy of phenolic retention and Maillard-derived products formation. Moreover, this advantage of simultaneous extrusion and enzymatic hydrolysis could be further exhibited in Chinese rice wine products via fermentation processing. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Science (John Wiley & Sons, Inc.) is the property of John Wiley & Sons, Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Food Science (John Wiley & Sons, Inc.) is the property of John Wiley & Sons, Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Discrimination of Chinese rice wines from four geographical origins ('Zhejiang', 'Jiangsu', 'Shanghai' and 'Fujian') in China was investigated according to their UV-vis spectra. The UV-vis absorption spectra of 112 samples in the wavelength range of 190-800 nm were collected. Then the absorption data was subjected to principal component analysis to reveal differences between samples and the potential possibility of using multivariate methods to distinguish differences. Classification models were developed by soft independent modelling of class analogy, linear discriminate analysis (LDA), discriminant partial least squares and support vector machine. Seven mathematical pre-treatments were applied to improve the performance of the multivariate classification models. Among the seven pre-treatments, standard normal transformation (SNV) was superior to the other six methods. The results showed that, compared with other models, SNV-treated LDA models achieved better performances with an average correct classification rate of 98.96% in the training set and 100% in the testing set. The results demonstrate that UV spectroscopy combined with chemometric data analysis, as a rapid method to classify Chinese rice wines according to their geographical origins, is feasible. Copyright © 2015 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Science (John Wiley & Sons, Inc.) is the property of John Wiley & Sons, Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The application of attenuated total reflectance infrared spectroscopy (ATR-IR), Raman spectroscopy (RS) and combination of ATR-IR and RS for measurements of total antioxidant capacity (TAC) and total phenolic content (TPC) of Chinese rice wine (CRW) were investigated in this study. Synergy interval partial least-squares (SiPLS), support vector machine (SVM) and principal component analysis (PCA) were applied to process the merged data from two individual instruments. It was observed that the performances of models based on the RS spectra were better than those based on the ATR-IR spectra. In addition, SVM models based on the efficient information extracted from ATR-IR and RS spectra were superior to PLS models based on the same information and PLS models based on ATR-IR or RS spectra. The overall results demonstrated that integrating ATR-IR and RS was possible and could improve the prediction accuracy of TAC and TPC in CRWs. [ABSTRACT FROM AUTHOR]

Effective fermentation monitoring is a growing need during the manufacture of wine due to the rapid pace of change in the wine industry. Ethanol and reducing sugar are two most important process variables indicating the status of Chinese rice wine (CRW) fermentation process. In this study, the potentials of Raman spectroscopy (RS) as a rapid process analytical technique to monitor the evolution of these two chemical parameters involved in CRW fermentation process and to group samples according to different fermentation stages were investigated. The results demonstrated that compared with the PLS model using all wavelengths of Raman spectra, the prediction precision of model based on the spectral variables selected by competitive adaptive reweighted sampling (Cars) was significantly improved. In addition, nonlinear models outperformed linear models in predicting fermentation parameters. After systemically comparison and discussion, it was found that for both ethanol and glucose, Cars-support vector machine (Cars-SVM) models gave the best results with the highest prediction precisions. Moreover, the results obtained from discriminant partial least squares analysis (DPLS) showed that good performances were obtained with an average correct classification rate of 94.9% for different fermentation stages. The overall results indicated that RS combined with efficient variable selection algorithm and nonlinear regression tool could be utilized as a rapid method to monitor CRW fermentation process. [ABSTRACT FROM AUTHOR]

There is a growing need for the effective fermentation monitoring during the manufacture of wine due to the rapid pace of change in the industry. In this study, the potential of attenuated total reflectance mid-infrared (ATR-MIR) spectroscopy to monitor time-related changes during Chinese rice wine (CRW) fermentation was investigated. Interval partial least-squares (i-PLS) and support vector machine (SVM) were used to improve the performances of partial least-squares (PLS) models. In total, four different calibration models, namely PLS, i-PLS, SVM and interval support vector machine (i-SVM), were established. It was observed that the performances of models based on the efficient spectra intervals selected by i-PLS were much better than those based on the full spectrum. In addition, nonlinear models outperformed linear models in predicting fermentation parameters. After systemically comparison and discussion, it was found that i-SVM model gave the best result with excellent prediction accuracy. The correlation coefficients ( R 2 (pre)), root mean square error (RMSEP (%)) and the residual predictive deviation (RPD) for the prediction set were 0.96, 6.92 and 14.34 for total sugar, 0.97, 3.32 and 12.64 for ethanol, 0.93, 3.24 and 9.3 for total acid and 0.95, 6.33 and 8.46 for amino nitrogen, respectively. The results demonstrated that ATR-MIR combined with efficient variable selection algorithm and nonlinear regression tool as a rapid method to monitor and control CRW fermentation process was feasible. [ABSTRACT FROM AUTHOR]

To help to control the qualities of Chinese rice wine brewed by enzymatically extruded glutinous rice, the correlation between the degradation degrees of extrudates and the qualities of Chinese rice wine were fully studied. Dextrose equivalent (DE), extent of gelatinization (GE), water solubility/absorption index (WSI/WAI), degree of polymerization (DP) distribution and scanning electron microscopy (SEM) of glutinous rice extruded respectively with 0.5‰, 1.0‰, 1.5‰ and 2.0‰ thermostable α-amylase (TS-αA)/mesophilic α-amylase (MS-αA) were determined. Surprisingly, more TS-αA decreased DE value while more MS-αA increased DE value. Both α-amylases reduced WSI with more enzymes. Besides, more TS-αA promoted GE while more MS-αA decreased GE. The contents of DP1, DP3, DP5, DP6, DP7 and other DP fundamentally affected the qualities of Chinese rice wine. DP1 content was significantly negatively correlated with total sugar and amino acid nitrogen, and positively correlated with alcohol degree. The contents of DP3, DP5 and DP6 were significantly positively correlated with amino acid nitrogen, and negatively correlated with alcohol degree. The contents of DP7 and other DP had a very positive correlation with total sugar. It's expected to control the qualities of Chinese rice wine by adjusting the relevant DP's contents. [Display omitted] • Dextrose content of extrudate was positively correlated with alcohol degree. • Water absorption index was extremely positively correlated with dextrose. • Extrusion with more mesophilic α-amylase more inhibited gelatinization. • Dextrose was not always positively correlated with dextrose equivalent. • Dextrose content could be adjusted by extrusion with mesophilic α-amylase. [ABSTRACT FROM AUTHOR]