Diagnosing Defects and Waste in an SME Bakery Using Lean Six Sigma

Product-quality problems create material losses and operational inefficiencies for resource-constrained food SMEs. This study diagnoses product defects and production waste at Ronalee Bakery, an Indonesian bakery SME, using selected Lean Six Sigma tools. Aggregate production and defective unit records from January to March 2024 were analyzed together with process observations and operational accounts. The DMAIC framework was used to organize the diagnostic process: the Define, Measure, and Analyze stages were applied to identify problems and their potential causes, whereas the Improve and Control stages were limited to proposed actions. Of the 101,421 units produced, 3,367 were recorded as defective, corresponding to an aggregate defective-product rate of 3.32%, which exceeded the company’s target of 2%. The assessment identified burnt bread, under-risen bread, torn or hollow texture, filling leakage, and non-standard weight, along with several relevant waste categories, including waiting, overproduction, overprocessing, inventory, and transportation. Potential causes were associated with operator capability, raw material and formulation consistency, oven condition, production planning, and facility layout. Proposed actions include standardized operating procedures, operator training, preventive maintenance, demand-based production planning, and layout adjustments. These findings provide a structured diagnostic basis for the future implementation and evaluation of quality-improvement actions in resource constrained bakery SMEs.

Keywords: Lean Six Sigma, defect diagnosis, production waste, bakery SME, exploratory case study

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