RESPONSE SURFACE METHODOLOGY FOR THE OPTIMIZATION OF SWEET POTATOES (Ipomoea batatas) DRYING PROCESS CONDITIONS

Abstract

The aim was optimization of sweet potatoes (Ipomoea batatas) drying process conditions with RSM to obtain high quality product is very vital as improper drying conditions can affect the composition of the dried sweet potatoes and thereby increases the risk of running into deterioration of the nutrient contents of the product and loss. Matured sweet potatoes were processed by washing, peeling and cut into required size. Samples obtained were dried in triplicate using DHG-9101 laboratory drying oven at different temperatures of 60, 65, and 70◦C and time of 480, 540 and 600 minutes at thickness size of 4, 5 and 6 mm by employing Design of Experiment (DOE). Statistical analysis based on central composite design was carried out. The significant factors were identified. The optimum conditions obtained were at a temperature of 60◦C, time of 480 minutes and thickness of 4 mm which resulted in final moisture content of 13.96%. From these results obtained, the use of response surface methodology in drying operation for optimizing sweet potatoes could be used. For further research, higher temperatures at lower drying time could be implemented. Also, other drying methods such as freeze drying and osmotic drying can be explored