Fermentation by Using Cellulolytic Microorganisms to Facilitate Stripping of Oil Palm and Its Effect on Oil Quality
Elisa Julianti, Sentosa Ginting, Hotnida Sinaga, Zulkifli Lubis, Pretty Peronika Sinaga

Department of Food Science and Technology, Faculty of Agriculture,
Universitas Sumatera Utara, Medan-Indonesia

Abstract

Sterilization process of fresh fruit bunch (FFB) is performed to inactivate the enzyme, facilitate the release of fruit from fruit bunch, and soften the fruit for ease of oil release from mesocarp. Nevertheless, heat sterilization could lead to poor bleachability of the resultant oil.
In this study a modification of the oil palm processing was carried out to facilitate the release of fruit from fruit bunches using microorganisms through the fermentation process. The purpose of this research is to determine the type of microorganism and the optimum fermentation time in the processing of palm fruit to produce palm oil with good quantity and quality. The types of microbes used were Bacillus subtilis, Aspergillus niger, Trichoderma harzianum, and a combination of Bacillus subtilis+ Aspergillus niger, and Bacillus subtilis+ Trichoderma harzianum. Fermentation is carried out for 20, 40, and 60 hours. The fruit that has been separated from the fruit bunch is then extracted by the Soxhlet extraction method using hexane solvent. The results showed that the interaction between microbial types and the fermentation time had a significantly different effect on free fatty acid levels, Deterioration of Bleaching Index (DOBI), beta carotene levels, and peroxide numbers. The interaction between microbial types and the length of fermentation gives a significantly different effect on the oil yield. Effective treatment to release the fruit from fruit bunches and produce oil with optimum quality is fermentation by Bacillus subtilis and 20 hours fermentation time.

Keywords: threshing fruit, fermentation, microorganism, palm oil

Topic: AGRICULTURAL PRODUCT TECHNOLOGY