Effect of Storage Temperature on the Cytochrome Oxidase and Polyphenol Oxidase Activities and Phenolic Content of Potatoes

Publisher Website
Google Scholar
Abstract
SUMMARY: Ontario and Pontiac potatoes, respectively representing varieties susceptible and resistant to precooking blackening, were examined for phenolic content and for cytochrome oxidase and polyphenol oxidase activities following storage at 4‐O and 50°F. The study was conducted for two consecutive years. In each of the two years the phenolic content of both varieties was significantly higher in potatoes stored at 40°F than in potatoes stored at 50°F. Both varieties had higher cytochrome oxidase and polyphenol oxidase activities when stored at 50°F than when stored at 40°F. The lower enzyme activities at 40°F may be responsible, in part, for the accumulation at that temperature of phenolic substances which serve as substrates for the enzymes. The higher phenolic content at lower temperatures may account for the greater discoloration of the potatoes.