Comparative Evaluation of Microbial Contamination and Nutritional Composition of Locally Procured, Prepared and Preserved Tomato Paste (Within Bwari and Gwagwalada Area Councils, FCT-Abuja) Using Glass Bottles

Abstract

This study evaluated the microbial contamination and nutritional composition of locally prepared and preserved tomato paste using glass bottles compared with industrial tomato paste. Four samples were prepared: homemade tomato paste (HP), homemade paste with preservative (HPP), vendor paste (VP), and industrial paste (IP) serving as control. Analyses were conducted at Month 1 and Month 3 for sterile samples, and at Month 3 for the spoilage study. The parameters analyzed included moisture, ash, crude protein, crude fiber, ether extract, nitrogen-free extract (NFE), pH, titratable acidity, vitamin C, and microbial load. Results showed significant differences (p < 0.05) in moisture content (ranging from 5.45 ± 0.05% to 6.80 ± 0.07%), crude protein (1.91 ± 0.01% to 2.65 ± 0.05%), and microbial load (2.1 × 10³ to 8.4 × 10⁵ CFU/g) between homemade and industrial samples. Sterile samples showed lower microbial counts compared to the spoilage study, indicating effective preservation through sterilization and glass bottle storage. The novelty of this study lies in its direct comparison of glass bottle–preserved tomato pastes under sterile and non-sterile (spoilage) conditions, providing practical insights into the potential of local preservation methods for improving food safety and reducing postharvest losses in Nigeria’s tomato value chain.