摘要：Processing method influences the functional compositions and utilization of foods. This study investigated the effect of soaking in water over time prior to the traditional method of drying and milling on some functional properties of bitter yam flour. Four equal parts of cleaned, peeled and sliced bitter yam tubers were respectively soaked in clean water for 6, 12, 18 and 24 h, dewatered, oven-dried at 50°C and milled, using standard procedures. The peak effect was recorded in the sample soaked for 24 h which increased respectively to 0.55±0.00 and 6.12±0.01% for bulk density and pH value. This represented a relative increase by 1.85 and 2.68%, respectively. Sample soaked for 24 h recorded a decrease in the water absorption capacity (3.01±0.01d%), oil absorption capacity (1.39±1.20d%), swelling index (3.20±0.01d%) and foam capacity (16.48±0.09d%). This represented a relative decrease of 4.14, 35.94, 1.23 and 6.09%, respectively. The observation, apart from that on the bulk density, was significant (p<0.05) and time dependent, indicating that soaking in water modified these properties of the bitter yam flour irrespective of the soaking time. The study provides insight on the possible application of soaking in clean water to optimize the studied functional compositions of bitter yam flour.
