Nowadays wine is increasingly enjoyed by a wider range of consumers. In partic- ular, Portugal is a top ten wine exporting country and exports of its vinho verde wine (from the northwest region) have increased by 36% from 1997 to 2007 [7]. To support this growth, the industry is investing in new technologies for both wine making and selling processes. Wine certification and quality assessment are key elements within this context. Certification prevents the illegal adulteration of wines (to safeguard human health) and assures quality for the wine market. Quality evaluation is often part of the certification process and can be used to improve wine making (by identifying the most influential factors) and to stratify wines such as premium brands (useful for setting prices).