QUALITY ASSURANCE IN THE PRODUCTION OF INSTANT COFFEE USING THE CUSUM CONTROL CHART

Abstract

This paper aims to evaluate stability and quality guarantee of the productive process regarding soluble coffee plant situated in the state of Paraná. The collected sample contents 4.598 observations of weight of 50 and 100 grams cans. The process of collection was made automatically during period of October 8th and December 5th 2004. ARIMA model’s residues were evaluated by the cumulated sum control charts (CUSUM) with “V” mask form, which showed that productive process is statistically unstable. This is evinces fragility of the process regarding the guarantee for the products that do not comply with requirements, mainly the weight of the 50 grams’ containers. The results suggest that employees should have more accurate attention to the discipline and control of everyday activities, besides banning mistakes made by them on the routine work that can be solved with the right orientation and changing equipment adjustment procedures. Key Words: ARIMA, Cumulated Cum Control Charts (CUSUM), Soluble Coffee Productive Process.