Effect of ascorbic acid and citric acid treatments on the functional and sensory properties of yam flour

Corresponding Author Email : [email protected] The study evaluated effect of ascorbic acid and citric acid treatments on the functional and sensory properties of yam flour. Yam (Dioscorea rotundata) tubers were washed, peeled and cut into thin slices of 1cm thickness. The slices were divided into 7 portions. The 1st portion served as control. The 2nd, 3rd, 4th and 5th portions were soaked in 2% (w/v) ascorbic acid, 4% ascorbic acid, and 0.5% citric acid and 1% citric acid solutions, respectively for 20 min. The 6th portion was soaked in a mixture containing 0.5% ascorbic acid and 0.5% citric acid while the 7th portion was soaked in a mixture containing 1% ascorbic acid and 1% citric acid. The slices were drained, sun dried, milled and sieved. The flours were analyzed for their functional properties. The yam flours were then used to prepare amala (yam flour dough) which were assessed for their sensory properties. The results showed that treatment of yam flour with ascorbic acid and citric acid improved the water absorption capacity, oil absorption capacity and least gelation concentration of the yam flour. However, the emulsion and foaming properties were not improved by the treatments. All the treatments significantly (P<0.05) improved the colour of the amala relative to the control. The taste, texture and flavour of the treated amala were not significantly different (P>0.05) from the control. The amala treated with 2% ascorbic acid was generally more preferred to the other amala samples.