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Publications (7)11.05 Total impact

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    ABSTRACT: Guaiacol, a potent volatile compound, has proven to be responsible for the distinct medicinal off-flavor in spoiled apple juice produced by Alicyclobacillus acidoterrestris. In this study, the artificial sensing system electronic nose (e-nose) was employed to detect this off-flavor compound in apple juice, using GC–MS and test panel evaluation as reference, as well as water as a comparative medium. Principle component analysis and linear discriminant analysis were employed to evaluate the capacity of e-nose for guaiacol detection in both media. A loadings analysis was used to examine the sensors' chemometric discrimination. Multiple regression analysis was applied to investigate the potential relationship between the concentration of guaiacol and the e-nose response. The detection limit based on e-nose for guaiacol in apple juice was 0.25–0.5 mg/L. For comparison, a 12-member test panel evaluation found an aroma detection threshold of 1.50 mg/L in apple juice, and the GC–MS detection limit for guaiacol in apple juice was determined to be 0.4 μg/L. In summary, the e-nose was capable of detecting guaiacol in apple juice, with significantly higher sensitivity than the test panel evaluation. This information should be useful for developing instrumental sensory detection techniques for rapid scanning of potential medicinal off-flavor in Alicyclobacillus-spoiled apple juice prior to consumer perception.
    Food Control 05/2015; 51. DOI:10.1016/j.foodcont.2014.11.037 · 2.82 Impact Factor
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    ABSTRACT: Suan-tsai and koumiss are traditional Chinese fermented foods. This study compared the dominant lactobacilli in suan-tsai and koumiss for their probiotic properties, cholesterol-lowering potentials and antioxidant activities. Thirty Lactobacillus strains were isolated from eight homemade suan-tsai samples (8 Lactobacillus plantarum and 6 Lactobacillus brevis) and seven homemade koumiss samples (7 Lactobacillus helveticus, 5 Lactobacillus acidophilus, 2 L. plantarum and 2 Lactobacillus casei), and they were subsequently analyzed for the above parameters. No significant differences were found between the mean antioxidant activities of the lactobacilli isolated from koumiss and suan-tsai, whereas the lactobacilli isolated from koumiss exhibited higher mean bile tolerance, adhesion to HT-29 cells, cholesterol removal and percentage of bile salt hydrolase-positive strains than did those isolated from the suan-tsai samples. Thus, koumiss could be considered a better source of potential probiotics, especially cholesterol-lowering probiotics, than suan-tsai.
    Journal of Functional Foods 01/2015; 12. DOI:10.1016/j.jff.2014.11.029 · 4.48 Impact Factor
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    ABSTRACT: The mechanism of patulin adsorption by inactivated cider yeast was studied by chemical modification and FTIR The results of patulin removal by various modified yeast biomass showed that the ability of patulin biosorption by acetone-treated yeast and NaOH-treated yeast increased siginificantly, while the methylation of amino group and esterification of carboxylate functionalities of yeast cell surface caused a decrease in patulin binding, which indicated that amino group and carboxyl group presented in the cell walls of yeast might be involved in the binding of patulin to the yeast. The FTIR analysis indicated that the main functional groups were amino group, carboxyl group and hydroxy group which are associated with protein and polysaccharides.
    Guang pu xue yu guang pu fen xi = Guang pu 03/2013; 33(3):672-6. DOI:10.3964/j.issn.1000-0593(2013)03-0672-05 · 0.27 Impact Factor
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    ABSTRACT: A simple and efficient microwave-assisted extraction of polyphenols from industrial apple pomace was developed and optimized by the maximization of the yield using response surface methodology. A Box-Behnken design was used to monitor the effect of microwave power, extraction time, ethanol concentration and ratio of solvent to raw material (g/mL) on the polyphenols yield. The results showed that the optimal conditions were as follows: microwave power 650.4 W, extraction time 53.7 s, ethanol concentration 62.1% and ratio of solvent to raw material 22.9:1. Validation tests indicated that the actual yield of polyphenols was 62.68±0.35 mg gallic acid equivalents per 100 g dry apple pomace with RSD=0.86% (n=5) under the optimal conditions, which was in good agreement with the predicted yield and higher than those of reflux and ultrasonic-assisted extraction methods. HPLC analysis indicated that the major polyphenols of apple pomace consisted of chlorogenic acid, caffeic acid, syrigin, procyanidin B2, (-)-epicatechin, cinnamic acid, coumaric acid, phlorizin and quercetin, of which procyanidin B2 had the highest content of 219.4 mg/kg.
    Journal of Separation Science 12/2010; 33(23-24):3751-8. DOI:10.1002/jssc.201000430 · 2.59 Impact Factor
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    ABSTRACT: Fourier transform-near infrared (FT-NIR) spectra of microorganisms reflect the overall molecular composition of the sample. The spectra were specific and can serve as spectroscopic fingerprints that enable highly accurate identification of microorganisms. Bacterial powders of one yeast and five bacteria strains were prepared to collect FT-NIR spectra. FT-NIR measurements were done using a diffuse reflection-integrating sphere. Reduction of data was performed by principal component analysis (PCA) and two identification models based on linear discriminant analysis (LDA) and artificial neural network (ANN) were established to identify bacterial strains. The reproducibility of the method was proved to be excellent (D(yly2) : 1.61 +/- 1.05-10.97 +/- 6. 65) and high identification accuracy was achieved in both the LDA model (Accuracy rate: 100%) and the ANN model (Average relative error: 5.75%). FT-NIR spectroscopy combined with multivariate statistical analysis (MSA) may provide a novel answer to the fields which need for rapid microbial identification and it will have great prospect in industry.
    Guang pu xue yu guang pu fen xi = Guang pu 11/2010; 30(11):2945-9. DOI:10.3964/j.issn.1000-0593(2010)11-2945-05 · 0.27 Impact Factor
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    ABSTRACT: In the title complex, [Co(C(22)H(15)O(5))(2)(C(2)H(5)OH)(2)], the Co(II) atom (site symmetry ) is coordinated by two O,O'-bidentate 4-(2-benzoyl-1-oxidoethen-yl)-3-hy-droxy-phenyl benzoate anions and two ethanol O atoms, resulting in a slightly distorted CoO(6) octa-hedral coordination. An intra-molecular O-H⋯O hydrogen bond in the ligand generates an S(6) ring. The dihedral angle between the aromatic rings joined to the acetyl-acetonate unit is 6.4 (2)°. The ethanol mol-ecule is disordered over two orientations in a 0.65 (3):0.35 (3) ratio. In the crystal, mol-ecules are linked by O-H⋯O bonds.
    Acta Crystallographica Section E Structure Reports Online 08/2010; 66(Pt 8):m1038-9. DOI:10.1107/S1600536810029776 · 0.35 Impact Factor
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    ABSTRACT: The sugar content and the matrix always are being changed during cider-making fermentation. In order to measure and monitor sugar content accurately and rapidly, it is necessary for the spectra to be sorted. Calibration models were established at different fermentation stages based on near infrared spectroscopy with artificial neural network. NIR spectral data were collected in the spectral region of 12 000-4 000 cm(-1) for the next analysis. After the different conditions for modeling sugar content were analyzed and discussed, the results indicated that the calibration models developed by the spectral data pretreatment of straight line subtraction(SLS) in the characteristic absorption spectra ranges of 7 502-6 472.1 cm(-1) at stage I and 6 102-5 446.2 cm(-1) at stage II were the best for sugar content. The result of comparison of different data pretreatment methods for establishing calibration model showed that the correlation coefficients of the models (R2) for stage I and II were 98.93% and 99.34% respectively and the root mean square errors of cross validation(RMSECV) for stage I and II were 4.42 and 1.21 g x L(-1) respectively. Then the models were tested and the results showed that the root mean square error of prediction (RMSEP) was 4.07 g x L(-1) and 1.13 g x L(-1) respectively. These demonstrated that the models the authors established are very well and can be applied to quick determination and monitoring of sugar content during cider-making fermentation.
    Guang pu xue yu guang pu fen xi = Guang pu 04/2009; 29(3):652-5. DOI:10.3964/j.issn.1000-0593(2009)03-0652-04 · 0.27 Impact Factor