Summary
Physiological studies were conducted on two varieties of potatoes — Ontario, which is susceptible to after-cooking blackening, and Kennebec — a variety which is generally free from this type of blackening.
The potatoes were stored at 50 F (10 C) and samples were removed for analyses every month. During the course of a year both varieties showed a gradual loss of ascorbic acid until the final sampling (July) when there was a slight rise. Ontario variety was consistently higher in ascorbic acid than Kennebec except at the June sampling.
The values for oxidation of ascorbic acid fluctuated and showed no definite relationship to propensity for blackening.
Turbidity of the extracts fluctuated during the year, showing a peak at the December sampling. The Ontario variety gave higher turbidity readings every month after the November sampling.
The Ontario was consistently lower in iodine-reducing values than the Kennebec potatoes.
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University of Pittsburgh, Pittsburgh, Pa.
Based on data submitted by Premitha Weeratne in partial fulfillment for the degree of Master of Science.
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Weeratne, P., Miller, E.V. & Murphy, H.J. Some observations on after cooking blackening of the Irish potato. American Potato Journal 41, 39–45 (1964). https://doi.org/10.1007/BF02863543
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DOI: https://doi.org/10.1007/BF02863543