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Plant Foods for Human Nutrition

, Volume 46, Issue 1, pp 33–39 | Cite as

Nutritional assessment of yam (Dioscorea alata) tubers

  • J. P. D. Wanasundera
  • G. Ravindran
Article

Abstract

The nutrient and antinutrient components of tubers from seven cultivars ofDioscorea alata were determined. The average crude protein content ofD. alata tubers was 7.4%. Starch (75.6–84.3%) was the predominant fraction of the tuber dry matter. Significant differences in crude protein and starch contents were observed among cultivars. Vitamin C content of the yam tubers ranged from 13.0 to 24.7 mg/100 g fresh weight. The results showed yams to be reasonably good sources of minerals. Phytic acid contents of the yams were low, with values ranging from 58.6 to 198.0 mg/100 g dry matter. Total oxalate levels in yam tubers were found to be in the range of 486–781 mg/100 g dry matter, but may not constitute a nutritional concern since 50–75% of the oxalates were in the water-soluble form. The overall results are suggestive of the nutritional superiority of yams compared to other tropical root crops.

Key words

Dioscorea alata Nutrient composition Oxalates Phytates Yam tubers 

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Copyright information

© Kluwer Academic Publishers 1994

Authors and Affiliations

  • J. P. D. Wanasundera
    • 1
  • G. Ravindran
    • 1
  1. 1.Department of Food Science and TechnologyUniversity of PeradeniyaSri Lanka

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