The production of dairy products is made up of manufacturing processes. Therefore, the Six Sigma DMAIC methodology can be used for continuous improvement.

We’ll take a look at three case studies of the DMAIC application in the dairy industry: two for milk production, and one focusing on yogurt manufacturing. Finally, we’ll refer to a video of a milk production line.

DMAIC Applied to Improving Efficiency of Milk Filling

In an article titled “Improving Efficiency of the Filling Line in a Dairy Industry,” the authors Eduardo Moró Pérez and José A. Morales discuss how DMAIC was applied to improve the efficiency of the filling line.

Their project charter is shown below.

six sigma dairy

Next, their SIPOC diagram.

six sigma dairy

And the subsequent Cause and Effect Diagram.

six sigma dairy


As stated in the project charter, one goal was to reduce the number of non-programmed stops.

This is the pareto analysis on the most recurrent stops.six sigma dairy


You can access the article here to read the details of their case study.

Using DMAIC to Reduce the Chilling Cost of Milk

In an article titled “Energy Saving Using DMAIC Approach in Milk Plant -A Case Study”, the authors Sunil Dutt Sharma and Harwinder Singh cover the DMAIC methodology used to reduce the chilling cost for milk.

The goal of the project was to reduce electricity consumption and save water.

During the Measure Phase, they produced the following Cause and Effect diagram.

After the Analyze, Improve, and Control Phases they were able to reduce the  refrigeration and chilling cost of Rs. 0.57 per liter to Rs. 0.39 per liter.

You can access the case study here.

DMAIC Used to Optimize the Level of Key Factors Affecting Yogurt Acidity

In an article titled “Application of Six-Sigma DMAIC Methodology in Plain Yogurt Production Process”, the authors Saeid Hakimi, Seyed Mojib Zahraee, and Jafri Mohd Rohani, cover the DMAIC phases for their case study.

Here is their summary.

Define: Yogurt production process was described and the CTQ characteristic for

yogurt production process according to VOC was defined as the rate of acidity.

Measure: The pH values were chosen as the CTQ functions for evaluating the rate of

the acidity in yogurt production process. In addition, five potential control variables

that influence the pH values of the yogurt were characterized.

Analyze: DOE was used to detect significant factors influencing the pH values of


Improve: The optimum settings of key process parameters were determined through

usage of desirability function method.

Control: Improved processes were standardized in the real production environment

and integrated into quality management system

This is the SIPOC diagram for their case study.six sigma dairy


And the Cause and Effect diagram for factors affecting the yogurt quality.

The article gives a detailed explanation of the experimental design that was used to determine the key factors and their optimal levels.

You can access their article here.

A Complete Milk Production Line Video

Finally, let’s see an actual milk production line in operation from SMF Germany.

You can view the video here.