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To propose a sensory evaluation method suitable for Qingzhuan tea, a representative Qingzhuan tea produced in Hubei was soak or spray boiled in order to analyze the effects of different boiling conditions on the sensory quality and the leaching rate of major chemical components of Qingzhuan tea. The sensory quality and chemical components of the tea infusions were compared with those of tea infusion obtained by the brewing method specified in the Chinese national standard. The results showed that the sensory quality of the boiled tea infusion was significantly better than that of the brewed tea infusion; the leaching rates of major quality components such as water extract, tea polyphenols, amino acids, soluble sugars and tea pigments were much higher in the former than in the latter. From the perspectives of sensory quality and the leaching rate of major quality components, tea infusion prepared by boiling for 2 min with a tea/water ratio of 1:80 and then standing for 2–4 min tasted moderate and had good internal quality. Further correlation analysis showed high correlation coefficients between the leaching rates of soluble sugars, theabrownine and water extract and taste quality. The results of this study provide a reference for the objective evaluation of the sensory quality of Qingzhuan tea and other types of compressed tea.

In order to investigate the differences in the characteristic aroma of black teas from different regions, the volatile aroma compounds of Keemun black tea, Yichang black tea, Dianhong black tea and Yingde black tea were identified by solid phase extraction (SPE) combined with gas chromatography-mass spectrometry (GC-MS) and were evaluated by gas chromatography-olfactory (GC-O). Odor activity value (OAV) calculation and correlation analysis between sensory aroma profile and key aroma-active compounds were performed to analyze the sensory attributes and chemical basis of the characteristic aroma of black tea. The results showed that the four black teas differed in the sensory attributes of seven aroma notes such as floral, sweet and herbal notes. Additionally, 24 differential key aroma compounds were identified (P 1). Geraniol contributed most to black tea aroma with the highest OAV in Keemun black tea (16 581.33), followed by Yichang black tea (7 463.65), Dianhong black tea (2 832.13) and Yingde black tea (467.96). Partial least squares (PLS) regression analysis and Pearson correlation analysis showed that β-ionone, geraniol and indole were responsible for the floral and sweet aroma of Keemun black tea, (Z)-3-hexenol and α-terpineol contributed to the fruity and woody aroma of Dianhong black tea, and 2-heptanol and (Z)-linalooloxide were responsible for the herbal aroma of Yingde black tea. In conclusion, this study has preliminarily clarified the characteristic aroma profiles of black tea from the four regions and their material basis at the molecular level.

A series; of novel ternary composite antioxidant systems; with different types; and mass ratios; were designed. These antioxidant systems were based on the BASF antioxidant Irganox®1010 ass a main antioxidant and Irgafos;®168 ass an auxiliary antioxidant at a basis mass ratio of 1: 1 together with Revonox®420 ass a carbon radical capture agent. Such antioxidant systems were applied for the modification of coal-based homopolypropylene (homo-PP) to enhance its thermo-oxidative aging performance. The resultant modified homo-PP was evaluated with oxidation induction time (OIT), yellow index, melting flow rate and mechanical performance. The results indicated that the modified homo-PP achieved optimum anti-oxidative performance by means of an antioxidant composite system based on Irganox®1010, Irgafoss®168, and Revo-nox®420. This composite antioxidant system resulted in the longest oxidation induction time of 9. 8 min, a yellow index of 1. 3, and a melting flow rate of 10. 7 g/10 min for the modified homo-PP. Moreover, the modified homo-PP gained an optimum anti-yellowing effect at a mass ratio of Irganox®1010 and Irgafoss®168 of 1: 2. These results provide a good reference for the design and development of high-efficient and long-term antioxidant system for the coal-based homo-PP. [ABSTRACT FROM AUTHOR]

The relative bioavailability of roxithromycin dispersive tablet in healthy volunteers was evaluated in this study. Its concentration in plasma was detected by high performance liquid chromatography (HPLC) after twenty healthy male volunteers were given each a single dose of 300 mg roxithromycin. The experiment data were obtained using DAS programme. The values of Cmax were 10.16+/-1.46 and 10.34+/-1.66 microg x ml(-1) at 2.33+/-0.61 and 2.28+/-0.62 h respectively; of t1/2 were 9.00+/-1.58 and 8.68+/-1.66 h respectively; of AUC0-->Tn were 143.32 +/-25. 80 and 138.93+/-22. 49 microg x h x ml(-1) respectively; of AUC0-->infinity were 158.63+/-26.86 and 153.77+/-24.75 microg x h x ml(-1) for test and reference drugs. Relative bioavailability of the tested roxithromycin was 103.63%+/-14.04%. The result showed that the two dispersive tablets are bioequivalent.