尼泊尔的葡萄生产状况及未来发展前景分析

在尼泊尔葡萄的种植面积很少,但市场需求量却很大.本文通过分析尼泊尔葡萄种植地的环境气候条件、葡萄生产状况及生产中存在的问题,提出了今后尼泊尔葡萄生产的建议及发展前景.     

无酒石浓缩红葡萄汁生产工艺研究

用纳滤法在红葡萄汁蒸发浓缩前去除其中的钾离子,使红葡萄汁在浓缩过程中不发生酒石沉淀,可提高蒸发的热效率,同时由于进行预浓缩,可大大缩短蒸发时间,降低成本,保证产品质量。低温酶法提取红葡萄色素,产品色泽好,较之调温提取色素对产品的风味影响小。     

对红提葡萄套袋纸的几点认识

目前国内水果套袋纸无法满足红提种植要求 ,本文从红提的生理特殊性、红提套袋纸的质量要求、物理性能指标、市场需求量以及红提套袋操作过程中应注意的问题几方面对红提套袋纸作了介绍     

Direct and Simultaneous Quantification of Tannin Mean Degree of Polymerization and Percentage of Galloylation in Grape Seeds Using Diffuse Reflectance Fourier Transform‐Infrared Spectroscopy

The direct and simultaneous quantitative determination of the mean degree of polymerization (mDP) and the degree of galloylation (%G) in grape seeds were quantified using diffuse reflectance infrared Fourier transform spectroscopy and partial least squares (PLS). The results were compared with those obtained using the conventional analysis employing phloroglucinolysis as pretreatment followed by high performance liquid chromatography‐UV and mass spectrometry detection. Infrared spectra were recorded in solid state samples after freeze drying. The 2nd derivative of the 1832 to 1416 and 918 to 739 cm^?1 spectral regions for the quantification of mDP, the 2nd derivative of the 1813 to 607 cm^?1 spectral region for the degree of %G determination and PLS regression were used. The determination coefficients (R²) of mDP and %G were 0.99 and 0.98, respectively. The corresponding values of the root‐mean‐square error of calibration were found 0.506 and 0.692, the root‐mean‐square error of cross validation 0.811 and 0.921, and the root‐mean‐square error of prediction 0.612 and 0.801. The proposed method in comparison with the conventional method is simpler, less time consuming, more economical, and requires reduced quantities of chemical reagents and fewer sample pretreatment steps. It could be a starting point for the design of more specific models according to the requirements of the wineries.     

外源性红花黄色素掺伪葡萄酒鉴别检测方法的研究

研究了天然色素红花黄掺伪葡萄酒的鉴别检测方法,样品经葡聚糖凝胶提取后用高效液相色谱法测定.确定了红花黄中掺两种主要呈色物质：红花黄A和红花黄B,在10～500mg/L范围内线性关系良好,回收率为85％～93％,相对标准偏差（RSD）＜4％.方法准确、灵敏、简单,适用于葡萄酒中外源红花黄色素的测定.     

Effects of site, season and viticultural practices on grape seed development

The effects of vineyard site, season, clone and viticultural management practices were examined as possible sources of variability in seed development between populations of grape berries, cvs Traminer, Riesling and Pinot Noir. Mean values for number and weight of seeds per berry were similar in most seasons and sites, but some were significantly different. In some but not all cases, smaller means for seed number per berry were associated with larger mean weight per seed. Trellising, training, pruning level, canopy manipulation and regulation of bunch number per vine had little effect on seed complement per berry except that mean weight per seed was smaller with minimal pruning. Reduction in water supply imposed after flowering did not alter seed number but reduced seed weight. Berries of boron-deficient vines had fewer and smaller seeds. The implications of seed development for berry development are discussed.     

简易覆盖对泰安地区酿酒葡萄园冬季土壤温湿度的影响

为了筛选适宜的简化防寒方法以替代树体下架埋土防寒,采用温湿度实时监控技术,检测了泰安地区最低气温情况,并对比研究了泰安地区冬季最冷时段葡萄园在简易覆盖和埋土防寒情况下土壤温度和湿度的变化特点。结果表明,1月所监测葡萄园冬季最低气温达到-15~-16℃;与埋土防寒相比,各种覆盖方式均能显著提高不同深度土层温度的最低值和平均值,保温效果依次是双毡+膜双毡=单毡埋土。其中,单层毡布覆盖操作简易,价格低廉,其地下5 cm、10 cm、20 cm及40 cm土层极低温度分别为0.91℃、1.28℃、1.69℃、2.80℃,均在0℃以上,明显优于埋土防寒的-2.95℃、-0.45℃、0.66℃、1.80℃;覆单毡后地下20cm土层的相对湿度为76.47%,较埋土防寒提高23.4%,利于葡萄度过干旱的冬季;覆单毡后赤霞珠的物候期比埋土防寒推迟7 d;但发芽率和坐果率没有显著差别。本研究表明,在冬季最低气温不低于-16℃的泰安或类似地区,采用覆毡的简易防寒方式有替代埋土防寒的可行性。     

Insoluble Grape Material Present in Must Affects the Overall Fermentation Aroma of Dry White Wines Made from Three Grape Cultivars Cultivated in Greece

ABSTRACT: Musts from 3 grape varieties were used to elucidate the effect of the presence of grape solids in must on the volatile composition of the resultant white wines. Volatile compounds were analyzed by GC/MS and GC/FPD except H₂S, which was measured spectrophotometrically. Increasing quantities of grape insoluble material decreased the substances that enhanced aroma of Savatiano and Batiki wines. Simultaneously, the levels of compounds that degrade wine aroma, when formed in large amounts, were increased. However, in Muscat of Hamburg wines, the levels of some volatiles were not influenced by must turbidity in the same way as in wines of the other cultivars.     

Grape brandy production,composition and sensory evaluation

Grape brandy is a spirit drink produced by wine distillation and is matured in wooden casks. According to legislation, it can be characterised by the geographical area where the grapes were produced, the grape variety used and the selected distillation and ageing techniques. Distillation increases ethanol concentration and aromatic constituents which are already present in grapes or are developed during fermentation and distillation. During maturation in wooden casks, compounds that contribute to the aroma and taste are extracted from the wood. Hence the spirit acquires the desired softer mouth feel, aromatic complexity and overall quality. Different methods of analysis are used in order to pursuit this process by analysing volatile and non‐volatile substances and correlate composition with quality. Analysis can also be useful in identification of brandy safety, potential adulterations, provenance and differentiation from other spirits drinks. © 2013 Society of Chemical Industry     

Determination of some biochemical properties of polyphenol oxidase from Emir grape (Vitis vinifera L. cv. Emir)

Polyphenol oxidase (PPO) was extracted from Emir grapes grown in Turkey and its characteristics in terms of pH and temperature optima, thermal inactivation, kinetic parameters and potency of some PPO inhibitors were studied. The optimum pH and temperature for grape PPO were found to be 4.2 and 25 °C respectively using catechol as substrate. K_m and V_max values were found to be 25.1 ± 2.72 mmol L⁻¹ and 0.925 ± 0.04 OD₄₁₀ min⁻¹ respectively. Of the inhibitors tested, the most potent was sodium metabisulfite, followed by ascorbic acid. The thermal inactivation curve was biphasic. Activation energy (E_a) and Z values were calculated as 251.4 kJ mol⁻¹ (r² = 0.996) and 8.92 °C (r² = 0.993) respectively. Copyright © 2006 Society of Chemical Industry