Statistical Evaluation of Process Variability on Vanilla and Chocolate Ice Cream Manufacturing Process

Shamika Thushara, Seneviratne Navaratne

Abstract: This paper represents a detailed assessment of process capability (Cp) and product consistency (Cpk) of Vanilla and Chocolate ice cream manufacturing process by applying certain quality tools such as X bar charts, R charts and fishbone analysis. Variable sampling plan was conducted to collect samples of Vanilla and Chocolate 80 ml, 500 ml, 1 L, 2 L and 4 L product volumes. Cp and Cpk of all ice cream products were lower than 1.0. Therefore, process variation is too high. This situation calls for either to reduce process variation or to widen the tolerances. Also for all products mean value of the mass in g/l was off target. Then the process should be adjusted to perform at the target value. Therefore it can be concluded that the manufacturing process of vanilla and chocolate all volume sizes are statistically incapable. The key root causes determined for the focused problem are no dosing mechanism in the filling machine, changes in filling volume, no proper method for monitoring weight of the product, random checking of product weight, changes in overrun and poor monitoring of overrun change.

Keywords: Process Capability, Product Consistency, Overrun, Fishbone, Mass in g/l