Application of the six sigma DMAIC in quality control of potato chips to reduce production defects

To produce competitive products, Small Medium Enterprises (SMEs), one of which is Agronas as a potato chip producer in Batu City, must continue to improve the quality of their products by minimizing production defects. Quality defects on potato chips occurred in color, crispness, wholeness, and size consistency indicators. This study aimed to identify and analyze the factors causing defects in potato chips and to design alternative improvement strategies. The research method used is Six Sigma Define, Measure, Analyze, Improve dan Control (DMAIC), with a sample size of 15 packs for each variable. The results showed that the main priority of the defined stage for quality improvement was crispness and size consistency with a Critical To Quality (CTQ) value of 80.2%. In the measuring stage, based on the process capability value, the final result is 82.3% which has a value above the industry standard in Indonesia of 69.2%. The result of the analysis of the DPMO value of 177,425 is equivalent to 2.43 sigma. The priority of improvement is the two highest defect levels of crispness and size consistency. Factors causing defects in potato chip crispness include limited manpower, lack of supervision and training, different levels of quality, manual packaging, and less than optimal frying. Alternative improvement strategies are labor controlling from the manager, providing training and process SOPs, supervising the selection of raw materials, and checking packaging equipment regularly. Factors causing defects in potato chips’ size consistency include limited manpower, lack of supervision and training, and the absence of a chip rating machine. Alternative improvements include training and process SOPs, supervision in grading chips, and procurement of grading machines.