Biodegradation of White Yam (Dioscorea rotundata Poir) And Water Yam (Dioscorea alata L.) Slices Dried Under Different Conditions

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R.N. Okigbo*
P.T. Nwakammah

Abstract

Two varieties of yams (water yam, Dioscorea alata L. and white yam, Dioscorea rotundata Poir) were processed into chips and dried under different conditions (Sun drying, oven during and ambient). Mycoflora of the stored yam chips were studied. Fusarium oxysporium were most abundant in the samples evaluated while other fungi which including Aspergillus niger, Rhizopus stolonifer, Fusarium solani, Botryodiplodia theobromae, Mucor sp., Geotrichium sp., Pichia sp., and Candida sp. Were isolated. These fungi depleted some quantities of nutrients, starch and proteins in the yams chips. Minute traces of aflatoxin were detected in the yam chips from which A. flavus was isolated. The use of dry yam chips was found to be safe for human consumption especially under controlled environment like the use of electric oven.


Keywords: Aflatoxin, biodeterioration, chips, fungi, yam


Corresponding author: E-mail: okigborn17@yahoo.com

Article Details

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Short Communications

References

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