Vitamin C (Ascorbic acid) levels in Irish potato (Solanum tuberosum) tubers purchased from shops and open markets in Cardiff, U.K. were determined in the raw, boiled and fried (chips) pieces by 2,6, Dichlorophenolindophenol dye (DCP) method in the laboratory. The chips were prepared in sunflower oil, corn oil and animal fat (Lard with antioxidant E. 321) respectively. Attempt was made to confirm the presence of vitamin C in the chips extracted by thin chromatography (TLC). Results obtained showed that the raw potato pieces contained 7.20–14.53mg vitamin C/100g, boiled pieces contained 3.54–8.88 vitamin C/100g while the chips pieces contained comparatively higher (7.92–17.00mg vitamin C/100g) level of the vitamin. The boiled potato pieces lost for greater amount (63–75%) of the vitamin C than the chips (0.05) influenced by the oil types used. Results obtained revealed that thin layer chromatography (TLC) method demonstrated the presence of vitamin C in the sample extracts. The vitamin did not, however move freely as the control suggesting that vitamin C in potatoes exist in a bound or combined form. The experiment results revealed that the chips contained higher mean vitamin C (10.9mg vitamin C/100g) than the boiled pieces (6.6mg vitamin C/100g), potato chips may not be a reliable source of vitamin C because of the bound or combined nature of the vitamin.

Keywords: vitaminC, ascorbic acid, potato, Solanum tuberosum

Plant Products Research Journal Vol. 9 2005: 1-5