Submitted to: Journal of Food Composition and Analysis
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/4/2003
Publication Date: 4/1/2004
Citation: Phillippy, B.Q., Lin, M., Rasco, B. 2004. Analysis of phytate in raw and cooked potatoes. Journal of Food Composition and Analysis.17(2):217-226.
Interpretive Summary: Phytic Acid is a major component of seeds that has positive and negative effects in animal nutrition and contributes phosphorus which pollutes lakes and streams via runoff of animal wastes from farms. It is believed that potatoes contribute appreciable amounts of phytate, but there are scant data in the literature to be certain how much is present in general. Therefore we determined the quantity of phytate in a number of raw and cooked potato products. On a dry weight basis these products contained less phytate than seeds, but the difference was not great. The phytate in raw and cooked potato products contribute substantially to human and animal diets and will need to be considered when evaluating the effects of phytate in nutrition and on the environment. Hence, this work will be beneficial to scientists involved in the food and environmental sciences.
Technical Abstract: The phytate (Myo-inositol hexakisphosphate) contents of eight varieties of potato (Solanum tuberosum) stored at 40 degrees Fahrenheit for approximately 3 months ranged from 0.021 to 0.047% of wet weight. The phytate was distributed evenly throughout raw unpeeled russet potatoes. There were no differences in phytate content between raw russet potatoes and those which had been boiled, baked or micro waved until fully cooked. French fries, potato chips and dehydrated potato flakes contained 0.174, 0.094 and 0.205% phytate, respectively, on a dry weight basis. Only phytate was detected in raw russet potatoes, but smaller amounts of inositol pentakisphosphate were also present in the fries, chips and flakes. Sufficient phytate is consumed in cooked potatoes in the United States to comprise a substantial portion of the daily intake of this multifaceted phytochemical.