Improving Crude Palm Oil Quality in Storage Tanks through PDCA-Based Control of Free Fatty Acids and Moisture Content
DOI:
https://doi.org/10.32734/jsti.v28i4.25547Keywords:
Crude Palm Oil (CPO), Fishbone Diagram, Free Fatty Acid (FFA), PDCA, Quality ControlAbstract
Maintaining CPO quality during storage is essential because elevated FFA and MC levels can reduce product quality, storage stability, and market value. This study investigates the levels of Free Fatty Acids (FFA) and Moisture Content (MC) in storage tanks and their impact on CPO quality using the PDCA framework supported by p-control charts and Fishbone Diagram analysis. The study aims to identify the factors affecting CPO quality and to formulate appropriate improvement strategies. Data on FFA and MC were obtained from the monthly laboratory reports of the mill and analyzed using p-control charts and Fishbone Diagrams. The results showed that 54 FFA samples and 71 MC samples exceeded the company’s established quality standards, indicating that moisture content was the dominant quality issue. The p-control chart analysis revealed that the storage process was statistically out of control, reflecting significant process variation during storage operations. Furthermore, the Fishbone Diagram identified several contributing factors related to human, material, machine, and method aspects, including operator inattentiveness, inadequate handling of Fresh Fruit Bunches, improper sorting processes, insufficient equipment maintenance, and suboptimal vacuum dryer pressure control procedures. Several corrective actions were proposed, including strengthening operator supervision, implementing a FIFO system for FFB handling, establishing clearer quality standards, enhancing equipment maintenance practices, and optimizing vacuum dryer operating procedures. The proposed corrective actions are expected to reduce non-conforming FFA and MC samples, improve process stability, and strengthen compliance with established quality standards.
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