Microbiological and Physicochemical Characteristic of Degrading Palm (Elaeis guineensis) Kernel and Cashew (Anacardium occidental) Nut Oils

Aim: For vegetable oil produce in Nigeria to be competitive in the international market and suitable for downstream applications. The Microbiological and Physicochemical Characteristic of oils are amongst the most important properties that must be studied.

Study Design: The study is design to isolate and identify microorganisms involved in degradation of palm kernel and cashew nut oils and to investigate the physicochemical characteristics of the oil samples during storage.

Place and Duration of Study: The study was conducted between April and September, 2015 at the Microbiology Laboratory of the Federal University of Technology, Akure, Ondo State, Nigeria.

Methodology: Palm kernel and cashew nut seeds were purchased from Oja Oba, Akure, Ondo State. Palm kernel and cashew nut oils were extracted using n-hexane by Soxhlet extractor. The oil samples were stored at room temperature (25°C ± 1) for three months. Microorganisms were isolated from the oil and identified every two weeks of storage. The effect of storage on the physicochemical characteristics (saponification value, peroxide value, acid value and specific gravity) of the oil samples was determined every two weeks of storage.

Results: The microbial profile of the associated organisms consists of Bacillus licheniformis, Staphylococcus aureus, Articosporium inflate, Aspergillus flavus, A. saprophyticus and Penicllium notatum. All the physicochemical parameters determined were increasing with time except the moisture content. Saponification values (SV) obtained for the palm kernel oil samples is 300 mgKOH/g and cashew oil is 400 mgKOH/g while no significant change was observed in the specific gravity of both oils.

Conclusion: The microbial load of the oil sample was low and the physicochemical property is evidence that the oil can be useful in production of soap and cosmetics.