葡萄酒成分分析与质量研究

通过对１９种葡萄酒的主要成分及其感官质量的分析评价，结果显示：葡萄酒中除含有糖、酒、酸、单宁、多酚外，还含有丰富的氨基酸、维生素Ｃ、矿物质及多种微量香味成分，其含量及感官质量因酒种及来源的不同而有所差异。在分析的基础上探讨了影响葡萄酒质量的主要因素，提出了提高国产葡萄酒质量的技术工艺措施；并建议加强对葡萄酒香味成分的分析研究，建立新的葡萄酒质量评价体系。     

Influence of technological practices on biogenic amine contents in red wines

To investigate the enological factors associated with biogenic amine content in wines, 224 samples of red wine were industrially manufactured. Differences in the amines and corresponding precursor amino acids of these wines due to their producing cellar and vintage were examined. The main effects of some technological procedures in the biogenic amine content of these wines was also described using multifactor analysis of variance. The results of the study indicate that vintage can clearly influence the amine contents of wines. It was also noticed that some enological practices widely used to enhance wine quality, such as the ageing of wine on lees and, mainly, longer grape skin maceration, strongly increased biogenic amine concentration. However, the addition of pectolytic enzymes did not favour the accumulation of any biogenic amine. With this study, it was also possible to conclude that the inoculation of wine with commercial malolactic starters minimises the levels of biogenic amines.     

Effect of micro-oxygenation on the evolution of aromatic compounds in wines: Malolactic fermentation and ageing in wood

The effect of micro-oxygenation on the aromas of two varietal wines (Tempranillo and Cabernet Sauvignon) when alcoholic fermentation is complete was examined. Several factors, such as whether malolactic fermentation (MLF) took place in barrels or stainless steel vats and ageing time in oak barrels, were taken into account. Major aroma components were studied using GC-FID and minor compounds were studied by GC-MS analysis before and after MLF and after 4 and 8 months of maturation in oak barrels. Sensorial analysis was performed to describe and quantify the different wine notes. Micro-oxygenation affects different compounds but the effect depends to a great extent on the grape varietal used; the effect of micro-oxygenation was more marked on the aroma of Cabernet Sauvignon wine than Tempranillo wines. The concentration of extractable compounds of wood was higher in wines after MLF in barrels than in wines after MLF in steel vats; wines with steel vat MLF had fewer toast and wood notes. The compounds that showed significant differences in concentration after 8 months of maturation were present in higher concentrations in wines fermented in barrels than in stainless steel vats. Barrel-fermented wines were sweeter, with wood and toast notes, fewer alcohol notes and fewer reductive notes.     

Aroma Composition and Sensory Quality of Cabernet Sauvignon Wines Fermented by Indigenous Saccharomyces cerevisiae Strains in the Eastern Base of the Helan Mountain,China

In order to improve the regional flavor peculiarity of Cabernet Sauvignon wine in the eastern base of the Helan Mountain, an Appellation of Origin in China, eight indigenous Saccharomyces cerevisiae strains were studied and evaluated. Compared to commercial control F15, indigenous N11424 present significant difference in the concentration of hexyl acetate, isoamyl acetate, ethyl hexanoate, diethyl succinate, and methyl benzoate, and the highest content of esters and least of alcohols were found in the wine made by N11424. By sensory analysis, N11424 wine was characterized with honey, pepper, as well as more fruit flavor, such as peach, cherry, clove, redcurrant, and blackcurrant. By odor activity value analysis, most of the high impact odorants were esters and the odor activity values of esters in most of indigenous strains were higher than in control F15.     

Use of preference mapping to relate consumer preference to the sensory properties of a processed meat product (tinned cat food)

The technique of generalised Procrustes analysis was applied to laboratory panel assessments of appearance, texture and aroma properties of ten commercial variants of tinned cat food. These assessments were made using free-choice profiling and were compared with results obtained from a subsequent fixed-choice profiling experiment. A consumer trial was also performed in a local supermarket to collect preference scores for the cat food, and these scores were related to the laboratory assessments using preference mapping. These techniques can be used by product developers to ascertain the properties of meat products that are important in determining consumer preference.     

葡萄酒感官评价结果的统计分析方法研究

在葡萄酒的感官评价中,由于品酒员间存在评价尺度、评价位置和评价方向等方面的差异,导致不同品酒员对同一酒样的评价差异很大,从而不能真实地反映不同酒样间的差异。因此,在对感官评价结果进行统计分析时,必须对品酒员的原始数据进行相应的处理,以真实反映样品间的差异。对有关数据处理方法的比较分析结果表明:标准化法不仅没有消除品酒员间的异质性,反而加大了品酒员间的差异;而置信区间法对原始数据进行调整,能有效地降低品酒员间的差异,真实地反映酒样间的客观差异。     

Differences in the phenolic composition and sensory profile between red wines aged in oak barrels and wines aged with oak chips

The aim of this study was to evaluate the similarities or differences in the phenolic composition and the sensory characteristics between wines traditionally aged in new French and American barrels for different periods of time, and wines aged for 30 days with different kinds (different geographical origin al toasting degree) of oak chips. This study was carried out with two grape varieties, Mencía and Tinta del País, and in two consecutive vintages. The results obtained indicated that it was not possible to obtain wines aged with chips with sensory characteristics similar to those aged for a long time in new barrels, independently. However, the results showed that the use of oak chips could be a good alternative for elaborating young wines with slight olfactory and gustative wood notes quite similar to wines aged in new barrels for short periods of time (about three months).     

Insights on the chemical basis of the astringency of Spanish red wines

The main goal of the present study is to provide an insight on the role played by non-volatile molecules on the different in-mouth attributes, particularly astringency. For achieving such goal, the main in-mouth sensory attributes of 34 oaked Spanish red wines were measured by a trained panel. The wine content in 30 sensory-active molecules was analysed by different HPLC based methodologies together with classical enological parameters and two proanthocyanidin indexes. Fourteen compounds (aconitic acids, polymeric proanthocyanidins, caftaric, caffeic and coutaric acids and seven quercetins) were found to be at concentrations above reported taste thresholds and to have a reasonably high range of occurrence. Two highly statistically significant models for astringency were built with those compounds. Even if the models could not be fully validated by sensory addition experiments, the research has demonstrated that wine astringency is driven by polymeric proanthocyanidins and by certain phenolic acids, the rate trans/cis-aconitic acid and flavonol profiles. The research has highlighted the existence of extremely complex interactions between non-volatile compounds on the in-mouth sensory perception. Particularly remarkable is the lack of additivity and potential antagonism found between the pairs cis/trans-aconitic acids, between aconitic and caffeic acids and between quercetin-3-O-galactoside and quercetin-3-O-glucoside. Also remarkable was the sweetness × astringent interaction and the matrix-dependence of the sensory responses elicited by flavonols. These results suggest the need for new paradigms and experimental procedures for fully decoding the real sensory relevance of individual non-volatile compounds in the overall wine flavour.     

气候变化对酿酒生产的影响

在浓香型白酒的生产过程中,直接影响白酒产量、质量的因素很多,气候的变化影响酿酒操作的入窖温度、入窖水分、入窖酸度等条件要求,在入窖淀粉含量、用曲量、用糠量、糟醅粮比等参数一定的情况下,不同季节酿酒对原酒质量特别是己酸乙酯的含量仍有一定的影响。