EVALUATION OF THE FUNCTIONAL AND SENSORY PROPERTIES OF BISCUITS PRODUCED FROM AERIAL YAM (Discorea bulbifera)

Biscuit samples were produced with wheat flour substituted with aerial yam flour at different levels of 10%, 20%, 30%, 40%, 50%, 60%, up to 100% respectively. The result of the functional properties obtained showed that bulk density of the aerial yam flour was 0.55g/ml, water and oil absorption of 3.86 and 2.68 respectively. Also swelling index of 5.9ml/g and pH of 5.13.These results were observed to be related to that of wheat flour. The proximate and sensory evaluation of these products were carried out using standard methods. The result obtained, indicated that the protein content of sample UV 100% aerial yam biscuit was 10.24 and was significantly different (p?0.05) to that of sample ST 100% wheat flour biscuit with 9.65.Similarly moisture content were generally high ranging from 5.31 in 100% wheat biscuit to 12.26 in 80%wheat flour+20%yam flour. From the sensory evaluation, the sample with 100% wheat flour had highest overall acceptability with 8.478, followed by 10% substitution with aerial yam flour, then 20% substitution with aerial yam flour, as well as 30%, 40% and 50% substitution which were accepted with values of:7.478, 7.1304, 6.3913, 6.0869,and 6.3043 respectively. Therefore, it could be ascertained that aerial yam flour could be used for substitution in wheat flour in production of biscuit and its related products up to 50% substitution and still be accepted by the consumers.