根据国际葡萄与葡萄酒组织的规定（OIV，2006），葡萄酒只能是破碎或未破碎的新鲜葡萄果实或葡萄汁经完全或部分酒精发酵后获得的饮料。生产葡萄酒是将葡萄这一生物产品转化为另一生物产品——葡萄酒。引起这一转化的主要媒介是一种称为酵母菌的微生物。酵母菌存在于成熟葡萄浆果的果皮上，它可以将葡萄浆果中的糖转化为酒精和其他构成葡萄酒的气味和味道的物质。葡萄酒的关键词是葡萄和酵母菌。葡萄酒是一种生物产品，它是从葡萄的成熟，到酵母菌及细菌的转化和葡萄酒在瓶内成熟的一系列有序而复杂的生物化学转化的结果。葡萄酒的这一生物学特征使它具有突出特性：多样性、变化性、不稳定性和自然特性。葡萄酒的质量很显然是我们追求的目标。那么，葡萄酒质量的构成因素有哪些呢？无论其风格如何，所有喝起来舒适的葡萄酒都有一个共同的特征，即它们表现出平衡，一种在颜色、香气、口感之间的和谐。平衡是葡萄酒质量的第一要素。葡萄酒质量的第二要素是风格，即一种葡萄酒区别于其他葡萄酒的所独有的个性。因此，真正的优质名酒首先必须是平衡，而且应具有其独特而优雅的风格。(As stipulated by International Organization of Vine and Wine (OIV, 2006), wine is the beverage by complete or partial alcoholic fermentation from crushed or uncrushed grapes or grape juice.Production of wine is a process in which one bio-product (grape) is turned into another bio-product (wine).The main medium that causes such conversion is a microorganism by the name of yeast.Contained in the skin of ripe grapes, yeast can convert sugar in grapes into alcohol and other substances that makes up the aroma and taste of wine.The key words for wine are grapes and yeasts.As a bio-product, wine is the result of a series of orderly and complicated biochemical conversions from conversion of yeasts and bacteria and bottle aging.The biological characteristic of wine makes it have some prominent features:diversity, variety, instability and natural characteristic.Obviously wine quality is what we are pursuing.Well, what are the contributing factors of wine quality?Despite the various styles, all the wines that taste good have a common property-a sense of balance, or a sense of harmony among color, aroma and mouthfeel.Balance is the No. 1 factor of wine quality.Its No. 2 factor is style, or the unique character that differentiates one wine from the others.Thus, the genuine quality wine must have, firs of all, the sense of balance, and then its unique and elegant style.)