• We will use regression trees and model trees to create a system capable of mimicking expert ratings of wine.• Because trees result in a model that is readily understood, this can allow the winemakers to identify the key factors that contribute to better-rated wines.• Perhaps more importantly, the system does not suffer from the human elements of tasting, such as the rater's mood or palate fatigue.• Computer-aided wine testing may therefore result in a better product as well as more objective, consistent, and fair ratings.