Review on Effect of Processing on Cassava Anti-Nutritional Factors and Impacts on Health

Abstract

Lamrot W Mariam and Fikrte Woldeyes

Cassava is a valuable source of food for developing countries, Different processing techniques exist to remove cyanogens andt heir effectiveness depends on the processing steps and the sequence utilized, and it often is time-dependent. The proximate composition of raw and boiled cassava tubers was not significantly different (P> 0.05), except in moisture, fat, carbohydrate and Energy value. High levels of the antinutrients in raw cassava tubers (20.56mg/100g Tannins; 1,16mg/100g oxalate and 3.36mg/100g phytate) make them unsafe and unsuitable for human consumption except after processing. Crushing and sun-drying cassava roots made into flour removes 96% to 99% of total cyanogens, whereas soaking and sun-drying into lafun or fufu, or soaking and fermenting and roasting into gari or farina, removes about 98% of cyanogens. For cassava leaves, which have 10 times more cyanogens than roots, pounding and boiling in water is an efficient process to remove about 99% of cyanogens. Other strategies to reduce toxicity include development of low-cyanogen cassava varieties and cassava transgenic lines with accelerated cyanogenesis during processing. Fermentation and oven-drying are efficient processing methods to remove phytate (85.6%) and polyphenols (52%), respectively, fromcassava roots. Sun-drying the leaves, with or without prior steaming or shredding, removes about 60% phytate. Cassava is a nutritionally strategic famine crop for developing countries and, therefore, reducing its toxicity and improving its nutritional value is crucial.

PDF