The organoleptic evaluation of the biscuit revealed that there were significant differences between the treatments for the organoleptic qualities such as taste, colour, texture, flavour and overall accept-ability (Table 2).
Taste is the primary factor which determines the acceptability of any product, which has the highest impact as far as market success of product, is concerned. The score for taste had also been de-creased from 7.5 to 5.95 with the increase in the level of substitution of soy flour. Biscuit containing 25% soybean flour was rated poorest in taste (5.95). The control treatment (T1) has the highest mean value and 25% soy flour added biscuit (T6) has the least mean value. The colour of the biscuit changed from creamy to dark brown, with a decrease trend in the mean scores from 6.95 to 6.5. The darker colour may be due to Maillard reaction between reducing sugar and protein (Dhingra and Jood 2000).
The texture of the crust was related to the exter-nal appearance of the biscuit top which implies smoothness or roughness of the crust. The texture of crust was decreased from 7.05 to 5.75 with the increase in substitution of soybean flour from 0 to 25% to the biscuits. The control treatment had the highest mean value and 25% soy flour added bis-cuit had the least mean value. Flavour of biscuit decreased from 6.95 to 5.45 with increasing in the substitution of soybean flour. This could be due to the beany flavour of soy flour (Akubor and Ukwuru 2005). Overall acceptability includes many implica-tions, which is the important parameter in or-ganoleptic estimation. The 10% soy flour added biscuits had the highest mean value and 25% soy flour added biscuits had the least mean value for the overall acceptability. At 10% level of soy flour incorporation, biscuits had higher scores for all the sensory attributes evaluated. Above this level, bis-cuits received lower sensory scores.