Spoilage Potentials of Biodeteriogens on Two Edible Oils - Groundnut (Arachis Hypogaea) and Palm (Elaeis Guineensis) Oil Sold in Rumuowoji Ultra - Modern Market, Port Harcourt, Nigeria

The spoilage potential and physicochemical characteristics of biodeteriogens on edible oils (groundnut oil and palm oil) sold in the market (Rumuowoji ultra-modern market) within Port Harcourt were examined. Spoilage bacterial genera were identified as Bacillus spp, Pseudomonas spp, Micrococcus spp and Staphylococcus spp while the fungal genera were identified as Aspergillus spp, Penicillium spp and Fusarium spp. The screen test for the utilization of the oil samples by the biodeteriogens showed that 7 out of the 9 bacterial species and 4 out of the 5 fungal species were capable of utilizing the edible oils as sole source of carbon and energy. Utilization of both oils by the mixed bacterial cultures of Bacillus spp. A1, Pseudomonas spp. A2, Bacillus spp. B1 and Staphylococcus spp. B3 resulted in maximum increases in total viable counts (TVC) of 1.5 x 108 cfu/ml as optical density (OD) increases to 1.31 nm while pH decreases with time from 7.10 - 5.65 over a 20 days' incubation. Similarly, the TVC, OD and pH of the mixed fungal culture of Aspergillus spp Af3 , Aspergillus spp Bf1 and Penicillium spp Bf2 on palm oil and groundnut oil where: 1.09 x 106 cfu/ml, 1.01 nm; 7.0 – 6.0 and 0.9 x 105 cfu/ml, 0.81nm, 7.2 - 6.1 respectively. The physiochemical analyses of the palm oil samples revealed that the highest mean free fatty acid (FFA) content and the peroxide value (PV) were 5.08% and 7.98 mEq/kg respectively in palm oil samples inoculated with mixed bacterial culture.