Improving Bread Quality and Production Process Using Taguchi’s Loss Function, Sigma Level: Vulgarization of Composite Breads

  • Tsapi T. Kevin
  • Tchasso T. Serge
  • Mbelle B. Samuel
  • Soh F. Bertin
  • A. Kuitche
Keywords: loss function, six sigma, cost of quality, bread quality, composite bread


Over the years, bread has become a staple food for millions of Cameroonians, with each Cameroonian consuming 33 kilograms of wheat each year. This has made bread production a highly lucrative business for manufacturers. According to Taguchi, a product does not cause a loss only when it is outside specification limit but whenever it deviates from its target value. This study measured the quality of bread already on the market with the objective of quantifying the financial losses to society and evaluated the process sigma quality level to guide efforts to improve the process. The study population consisted of 400 bread samples of two most consumed types of bread, selected using a systematic random sampling method from a total of four bakeries and five sale points in Bamenda and Bafoussam Cities of Cameroon. The results indicated that 15% of the breads from Bakery D did not meet the weight specifications, while 42% of the 600g bread presentation did not meet the specifications. The remaining bakeries had a weight deviation of between 95% and 98%. The losses for the products with presentations of 600g, 200g (Bakery A), 200g (Bakery B), 200g (Bakery C), and 200g (Bakery D) are 59.81 xaf, 44.22 xaf, 23.03xaf, 26.91xaf, and 35.14 xaf, respectively. The 600g bread presentation incurred the greatest economic loss when it deviated from the nominal value, while bakery A exhibited the best sigma quality level of the process, 5.61 sigma. It was recommended that various stakeholders throughout the country consider substituting portions of wheat flour with cassava flour in the manufacturing of composite bread. Additionally, it was suggested that the weight and quality of bread available on the market be monitored and controlled in order to minimize losses to society.


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How to Cite
Kevin, T. T., Serge, T. T., Samuel, M. B., Bertin, S. F., & Kuitche, A. (2024). Improving Bread Quality and Production Process Using Taguchi’s Loss Function, Sigma Level: Vulgarization of Composite Breads . European Journal of Science, Innovation and Technology, 4(3), 96-114. Retrieved from