TY - JOUR T1 - The Browning Capacity of Grapes. II. Browning Potential and Polyphenol Oxidase Activities in Different Mature Grape Varieties JF - American Journal of Enology and Viticulture JO - Am J Enol Vitic. SP - 157 LP - 162 DO - 10.5344/ajev.1983.34.3.157 VL - 34 IS - 3 AU - Jean C. Sapis AU - Jean J. Macheix AU - Robert E. Cordonnier Y1 - 1983/01/01 UR - http://www.ajevonline.org/content/34/3/157.abstract N2 - For a large number of grape varieties, browning potential and polyphenol oxidase activities were measured at maturity. Classification in accordance to these criteria was made. It was confirmed that polyphenol oxidase of the grape is a strongly bound enzyme and that browning is concentrated for a large part in the non-soluble fractions of the juice. Phenolic substrate appears to be the limiting factor in browning. ER -