Sherry wine vinegars: phenolic composition changes during aging

Production of Sherry wine vinegar encompasses a variable period of aging in wood. Changes in phenolic compounds during Sherry vinegar aging were studi ed. Samples were divided according to their aging period in wood (less than 2 years, more than 2 years) and phenolic compounds determined in a total o f 38 samples by means of HPLC and Photodiode Array Detection. Results of Mu ltiple Analysis of Variance (MANOVA) confirms that there were significant d ifferences among both groups. Good recalling rates were achieved in both Li near Discriminant Analysis LDA (mean = 92.9%) and Artificial Neural Network s trained by Back Propagation (BPANN) (mean = 90.4%) whilst prediction abil ities are more discrete. Applying the forward selection of variables, six v ariables were selected according to the Wilks' lambda criterion: gallic aci d, 5-hydroxymethylfuraldehyde, coumaroyltartaric acid glycoside, p-hydroxyb emoic acid, caffeic acid and isoquercetrin. Three of these compounds (galli c acid, hydroxymethylfuraldehyde and coumaroyltartaric acid glycoside) were shown to have an increasing trend through most aging systems. (C) 1999 Can adian Institute of Food Science and Technology. Published by Elsevier Scien ce Ltd. All rights reserved.