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991.
超滤法生产的纯生黄酒非生物稳定性的研究 总被引:7,自引:0,他引:7
用截留分子质量为 30 0 0 0u和 10 0 0 0u的超滤膜对生黄酒进行过滤 ,定量测定了与黄酒非生物稳定性有关的几种物质———酶、蛋白质、多酚、铁离子、戊聚糖等 ,并且通过光散射实验 ,考查了超滤前后酒液中平均粒度的变化。结果表明 ,超滤处理后 ,酒液中淀粉酶、糖化酶和蛋白酶都能达到去除的要求 ;蛋白质、多酚、铁离子、戊聚糖等物质的含量均呈减少的趋势 ;而且超滤处理后的酒样平均粒度降低 ,从而说明了超滤技术对纯生黄酒的非生物稳定性起到了一定的提高或改善作用。 相似文献
992.
该试验以无花果、仙人掌果为原料制备果酒,并研究复合果酒的最优发酵工艺。通过单因素试验及响应面试验,探讨了酵母接种量、发酵温度、初始pH值、初始糖度、发酵时间对无花果-仙人掌果酒发酵产酒精量的影响。结果表明,最佳发酵条件为仙人掌果∶无花果=1∶2,酵母接种量0.04%,发酵温度25 ℃,初始pH值3.40,初始糖度20 °Bx,发酵时间7 d,在此优化条件下,制得无花果-仙人掌果酒的酒精度为11.01%vol,感官评分为97分,总花青素含量为50.68 mg/100 mL。果酒鲜艳紫红,酒体清澈,具有浓郁的果香和醇厚的口感。 相似文献
993.
Sealing system and bottle storage position effects on the evolution of white and red wines were analyzed. The sealing systems were natural‐cork stopper, colmated‐cork stopper, agglomerated‐cork stopper, polyurethane‐powdered‐cork (PPC) stopper, plastic stopper, and metal screw‐top. Chemical analysis and sensory analysis showed that wine is better preserved when the bottles are kept horizontally. The sealing systems that allowed the most suitable evolution were the natural‐cork stopper, the colmated‐cork stopper, and the PPC stopper. The agglomerated cork produced faster wine oxidation when the bottles were kept vertically. The plastic cork and the screw‐top allowed oxidation in the wine more quickly than the other systems. 相似文献
994.
Pablo Estévez Mª Luisa Gil & Elena Falqué 《International Journal of Food Science & Technology》2004,39(1):61-69
The must obtained from Palomino grapes was inoculated with seven different commercial yeast strains (three Saccharomyces cerevisiae cerevisiae– MO5, CEG and IOC BR 8000 and four Saccharomyces cerevisiae bayanus– ALB, KD, REIMS and IOC 2007) and fermented under identical conditions. Standard chemical analyses were done on the final industrial wines and the major volatile compounds extracted and analysed by gas chromatography coupled to mass spectrometry. No differences were found in gross chemical composition, but the wines had significantly different volatile characteristics and the results demonstrated that large sensory differences were generated by the different yeast strain that had been used in the vinification. The major constituents that contributed to the volatile composition in this wine were the higher alcohols, ethyl esters, acetates, fatty acids and volatile phenols. In terms of floral and fruity odours, the best results were obtained for the wines inoculated with IOC 2007, ALB and REIMS S. cer. bayanus strain. 相似文献
995.
996.
997.
葡萄酒酿造副产物的开发利用 总被引:2,自引:0,他引:2
积极开展葡萄酒酿造副产物综合利用的研究,化废为宝,具有十分重要的意义。该文主要论述了葡萄酒糟的再发酵利用;酒石酸氢钾、葡萄籽油、葡萄色素、丹宁的提取,以及利用葡萄酒糟做饲料等内容。 相似文献
998.
黄酒生产中酵母菌发酵性能研究 总被引:4,自引:0,他引:4
随机分离黄酒生产用酒饼中的酵母菌菌株,比较不同来源的酵母菌细胞形态、细胞大小、发酵力、酵母悬浮细胞数、总降糖、酒精度、凝聚力、致死温度和耐酒精度,研究黄酒生产中酵母菌的发酵性能。结果表明,不同来源的7株酵母菌中,总降糖、酒精度、发酵力、凝聚力有显著差异,细胞形态、大小、致死温度、耐酒精度等没有明显差异。 相似文献
999.
J.D. GREENOUGH H.P. LONGERICH S.E. JACKSON 《Australian Journal of Grape and Wine Research》1997,3(2):75-83
Analysis of elements in wines by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) may help protect prestigious wineries from counterfeit wines and permit source confirmation for government certification. Thirty-three elements were determined in 17 white and 10 red wines from 13 Okanagan Valley (B.C, Canada) wineries. Multidimensional scaling (MDS) shows that red wines are similar to red wines and white wines similar to white wines. Apparently processing (contact between must and skins during fermentation) affects Li, Zn, Mo, Mg, Ba, Ca and P. However, wines from grapes from the same vineyard tend to be most similar, regardless of the vintage, grape variety or winery that processed the grapes. This implies that wine element 'fingerprints' are relict soil signatures that survive metabolic and winery processing. Elements in wines behave according to geochemical water solubility principals indicating that soil Eh, pH and complexion agents affect element uptake. There is no clear relationship between vintage year or grape variety and wine element composition. However, discriminant analysis indicates that combinations of elements (˜6) from several geochemical groups can accurately classify the wines according to vineyard. Twenty-five elements (Cu, Ni, Ca, Fe, B, Mg, As, Sb, Mn, Sn, P, Al, Zn, U, Sr, Cr, S, Co, Ba, La, Mo, Ti, Pb, Ce and V), determined with high precision by ICP-MS, correlate strongly with vineyard of origin. The limited number of wines available for study requires that conclusions be confirmed with future testing. 相似文献
1000.
C.R. ChenH.S. Ramaswamy 《LWT》2002,35(5):415-419
Kinetics of color and texture changes in ripening bananas were investigated as a function of storage temperature (10, 16, 22, 28 °C). Color was evaluated in terms of L, a and b values as well as the total color difference (ΔE) representing the residual deviations from the ripe stage. Puncture force (PF) was used to evaluate the texture properties of banana. The results indicated that the time dependence of L, ΔE and PF values followed a logistic model, while a and b values were well described by a simple zero-order and fraction conversion models, respectively. The Arrhenius equation adequately described the temperature dependence of the reaction rate constants for both color and texture parameters, from which the activation energies and rate constant at reference temperature 15 °C were obtained. There were significant linear correlations between color parameters (L, a, b, ΔE) and texture parameter (PF). 相似文献