ABSTRACTThe effect of freezing on ascorbic acid losses during water heating of potato cylinders at 50°, 65° and 85°C was studied at different periods of time. Loss of ascorbic acid in frozen potato was mainly by diffusion and greater than for fresh potato. The estimated apparent diffusivities of ascorbic acid in frozen potato during water blanching were 13.64 × 10‐10m2/sec at 50°C, 17.78 × 10‐10m2/sec at 65°C and 20.30 × 10‐10m2/sec at 80°C. The activation energy of the diffusion process was 3,007 cal/mol. Ascorbic acid aparent diffusion coefficients in potato tissue with pre‐freezing treatment were between 80 and 90 of ascorbic acid diffusion coefficients in water in t
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