Validation of Taguchi design using a quality parameter of cosmetic soap manufactured in a local industry

Abstract

The objective of this study is to investigate the applicability of Taguchi method to the production process of a local industry. Harishchandra Mills (Pvt.) Ltd, Matara, which is engaged in soap manufacturing process has been selected as the local industry. This process is entangled with different kinds of variables. Four critical variables -two types of oil, coconut oil (a 1 ) and palm oil (a 0 ), on the basis of high and low saponification values, two levels of caustic soda (b 0 , b 1 ), and two different saponification temperatures, 70 (c 0 ) and 80 (c 1 ), with and without stirring process for saponification (d 1 , d 0 ) were adopted. The results obtained for Total Fatty Matter (TFM) was used to calculate optimum value (Yopt) for each treatment with and without replicates. The results for Yopt for TFM with and without replicates were 75.98%, and 76.66%, respectively. The best treatment combination under this method was a 1 b 1 c 1 d 1 for the same sequence of quality parameters given above. The same best treatment combinations were also obtained for the validation test, fourfactor experiment design and block design with and without replicates.