Changes in Microbiological Quality of Table Spreads Produced from African Pear (Dacryodes edulis) Pulp during Storage

Abstract

African pear (Dacryodes edulis) pulp was extracted and pasteurized. The pasteurized pulp was homogenized with different levels of food grade additives to form table spreads of samples A to H while sample I was left without preservative. The spreads were packed in sealed glass containers and stored at room temperature (28±20C) for 4 weeks to evaluate the changes in microbiological quality of table spread during storage period. Samples were collected in a weekly interval to study the microbiological assay of the spread starting from week zero to the last week. High total bacteria count of 1.8x107CFU/ml was seen in sample I (spread without preservative) at week zero, this increased significantly to 8.1x108CFU/ml after 3 weeks of storage and TNTC (too numerous to count) after 4 weeks of storage at 28±20C. The least growth were observed in samples A and C with bacteria counts of 8.1x107CFU/ml and 3.5x107CFU/ml, respectively. The least fungi count of 2.0x106CFU/ml was noted in sample C after 4 weeks of storage while the highest fungi count of 4.5x107CFU/ml was seen in sample I after 4 weeks of storage at room temperature (28±20C). The suspected microorganisms based on their morphology were; E. coli, Staphylococcus aureus, Salmonella specie while fungi were Penicillium specie and Aspergillus specie. Deterioration sets in significantly after two weeks storage as total bacteria and fungi counts rose above 1.0×107 and 1.5×106, respectively. The microbiological quality of the samples was stable up to the second week of storage except sample I (without preservative).