Abstract

The aims of this study were to investigate the rancidity and chemical properties of oil palm decanter meal (OPDM) after been kept over an extended period of time.Samples were collected daily and analyzed for some rancidity properties, including peroxide value (PV) and thiobarbituric acid (TBA), and for chemical composition, including proximate analysis, fiber, mineral and fatty acid (FA) content. The correlation coefficient between time of storage and the rancidity (PV and TBA) of OPDM were positive with R² of 0.9792 and 0.9678, respectively. During ten days of observation, the compositions of long-chain FA, including stearic, oleic, linoleic and linolenic except for palmitic were significantly (P<0.05) different. The compositions of short-chain FA, including acetic, propionic, isobutyric, butiryc, isovaleric and valeric, were also significantly (P<0.05) different. Furthermore, PV and TBA were significantly (P<0.05) different during the extended time of 10-days storage. The correlation coefficient between PV and long-chain FA (palmitic, stearic, oleic, linoleic, and linolenic) were 0.61, 0.16, -0.82, -0.3 and -0.84, respectively, and the correlation composition between TBA and the composition of long-chain FA (palmitic, stearic, oleic, linoleic and linolenic) were 0.40, 0.34, -0.91, -0.02 and 0.62, respectively. It could be summarized that physically and chemically, the fresh OPDM might be used as an alternative feed, especially for ruminant.

Key word: Oil palm decanter meal, fatty acid, oxidation, rancidity, peroxide, thiobarbituric.