THE RELATIONSHIP OF CHIP COLOR WITH STRUCTURAL PARAMETERS OF STARCH

Seven potato cultivars (Norchip, Monona, Onaway, Snowden, Atlantic, Sa ginaw Gold, Novachip) and the seedling ND860-2 differing in their susc eptibility to low temperature sweetening were analyzed to determine if starch structural stability parameters could be used to consistently predict and/or monitor chip color (Agtron score) of potatoes during st orage at 4 and 12 C. Fresh tissue gelatinization temperature (Tp) was significantly correlated (P less than or equal to 0.05) with chip colo r for all cultivars except Onaway, Snowden and Atlantic for tubers har vested in 1993 when stored at 12 C. No correlations existed between Tp of isolated starch and chip color (P>0.05). In 1994 no correlations e xisted between Tp of fresh tissue, Tp of starch and chip color at eith er 4 or 12 C (P>0.05). Prediction of chip color based on starch stabil ity parameters was not possible. Starch crystallinity, amylose content and starch granule size distribution could not be used to predict or monitor chip color in stored tubers.