Abstract

The sap of the oil palm tree (Elaeis guinnesis) serves as a rich substrate for various types of microorganism to grow. However, it is a source for producing the traditional wine, palm wine. This study was done with the aim to compare the microorganism found in palm wine samples obtained from living and felled oil palm tree at different time of fermentation. The palm sap samples were collected and allowed to ferment for three days (72 hours). Samples were collected twice a day for three days and analyzed for the presence of microorganism using standard microbiological procedure. The result reveals that the microbial load varies with fermentation time across each sample. With respect to the microbial population, aerobic mesophilic counts ranging between 7.08 x 10⁷ and 6.20 x 10⁸ cfu/ml and 4.01 x 10⁷ and 1.60 x 10⁹ cfu/ml respectively, lactic acid bacteria count ranging between 1.3 x 10⁷ and 6.75 x 10⁸ cfu/ml and 1.65 x 10⁷ and 9.75 x 10⁸ cfu/ml respectively. Yeast counts between 4.0 x 10⁵ and 6.00 x 10⁷ cfu/ml and 3.43 x 10⁵ and 5.68 x 10⁷ cfu/ml respectively. Across the sample from the two sources (living and felled oil palm tree) acetic acid bacteria counts between 5.6 x 10⁷ and 6 x 10⁷ cfu/ml and coliform bacteria between bacteria 5 x 10³ and 7.50 x 10³ cfu/ml. Further microbiological analysis revealed the various bacteria and yeast isolated from the palm wine samples. From the comparative analysis of the microorganism gotten from palm wine from life and felled oil palm tree at different time, the result revealed that at the beginning of fermentation on the first day, the isolates identified were mostly bacterial contaminants and the yeast Saccharomyces cereveisae. No lactic acid bacteria at the initial stage of tapping from either the palm wine from the living or felled oil palm tree. Lactic acid bacteria (Lactobacillus spp) was isolated from the 2^nd day of fermentation from both living and felled palm sap and remained till the third day of fermentation in both palm wine samples. Acetic acid bacteria, Acetobacter aceti and Gluconobacter spp were present in both sample from the third day of fermentation due to the buildup in alcohol concentrations on the third day. Zymomonas mobilis was also present in the palm wine from living tree but absent in the felled tree palm wine. Generally, Lactic acid bacteria (LAB) and Acetic acid bacteria (AAB) were both present in the samples only after the onset of fermentation from the second and the third day of fermentation respectively. It is therefore recommended that the microbiology and the biochemistry of palm wine must be fully understood.