Evaluations of some Selected Yam Flour Production Variables on Drying Time and Final Moisture Content of Sliced Dried Yam

Abstract

The time required for drying to save moisture content is important to yam flour millers in the production of yam flour. Understanding the  effect of some processing variables on the final moisture content and drying time is an important theoretical and experimental  cornerstone in optimizing the drying processes used in food industries to produce yam flour. As a result, the purpose of this research is  to determine the effect of some selected processing variables and final moisture on sliced yam for the production of yam flour. A 4 by 5  factorial response surface methodology (RSM) of design expert version 6.0.8 was used to identify the relationship between the response  functions and the process variable of the dried yam chips in order to study the effect of these selected production variables. Soaking time  (5, 10, 25, 40, and 55 minutes), soaking temperature (40, 60, 80, 100, and 120 degrees Celsius), drying temperature (45, 60, 75, 90,  and 105 degrees Celsius), and chip size in volume are the four factors considered with their levels (20, 50, 90, 160, and 230 cm3). The functional relationships between the selected processing variables were established using an empirical model that was validated using  the design expert software's coefficient of determinant (R2). The drying time was observed to decrease from 1736 to 334 minutes as the  drying temperature increased from (45 to 105ºC), while the effect of soaking time and yam variety on drying time was insignificant  (P<0.05). It was also discovered that as the soaking temperature rises from 40 to 80 degrees Celsius, the final moisture content falls from  13 to 7%. The study concluded that the investigated processing factors must be taken into account in the modeling of drying operations  and the design of equipment for the production of yam flour.