Post-Harvest Practices Effect on the Quality Protocol of Acacia seyal Gum from Sudan

Abstract

The paper investigated the effects of post-harvest practices on the physicochemical properties and microbial content of Acacia seyal (Talha) gum at various stages. A total of fifteen gum samples were collected from three distinct regions in western Sudan namely; Buram, Hijleij, and Deain. The investigations were carried out on the gum Arabic samples at different stages: extraction from trees, collection in jute sacks, transportation facility, storage in production sites, storage in factories, and during cleaning and processing phases before exporting the product to external markets. The findings indicated a significant increase (p= 0.05) in the gum's coloration as it passed from the collection sites through storage facilities to the factory. Subsequently, a notable decrease in color was observed after the cleaning process, ultimately reaching the final export-readiness stage. During the cleaning and processing stages, various impurities were systematically removed. These include bark, residue, sand, and other foreign materials. Furthermore, visual grading performed by laborers during cleaning allowed for the differentiation of gum lots based on color, facilitating a blending process aimed at standardizing the coloration of the final export product. No significant positive correlation was noted among the other physicochemical properties, except for optical rotation (R= 0.65), which mirrored the pattern observed in coloration. The microbial analysis revealed a consistent trend across samples from different areas, though the intensity varied. For instance, the total bacterial count was highest in the gum immediately after harvesting and increased during subsequent handling, before experiencing a dramatic decrease in the final stages.