Microbiological evaluation of gum Arabic (Acacia senegal Gum) from tree to store and during processing

Abstract

The microbial load and hygienic status of gum Arabic was determined at various stages of production storage and processing. The mean value for total bacterial viable count ranged from 1.3×102 to 4.6×104 Colony Forming Unit/gram (CFU/g), viable mould count was 0.3×10 to 10.1×103 CFU/g and for aerobic spore-forming bacteria the mean value ranged from 1.3×10 to 2.6×104 CFU/g. The general trend in that the microbial load of gum Arabic decreases as one proceeds from time of exudation on the tree to the final processing stages. Hygienically, all gum samples collected aseptically from the trees were free of Staphylococcus aureus, Salmonella spp and Coliforms. Salmonella spp and Coliforms were first detected on the gum samples collected by ferments while still in the field. Staphylococcus aureus was first detected in samples from the village market. Escherichia coli was not detected in any sample of gum arabic. In addition to Salmonella spp, Staphylococcus aureus and Bacillus spp, other bacterial genera identified in gum arabic include Pseudomonas spp, Moraxella spp, Enterobacter spp, Providencia spp, Serratia spp, Klebsiella spp, Proteus spp and Cedecea spp. The fungal genera identified were Aspergillus spp, Penicillium spp and Curvularia spp. Yeasts were not detected in any gum arabic sample.