Keywords
Proximate composition
Irish and sweet potatoes
How to Cite
Abstract
This study investigates the microorganisms present in healthy, bruised, and spoiled Irish and sweet potatoes and this was done using standard microbiological methods. The results reveal varying microbial counts across different stages of potato quality. In Irish potatoes, Total heterotrophic bacteria (THB) counts ranged from 3.25x105 to 1.9x106 CFU/g in the healthy samples, increasing to 5.7x105 to 1.12x106 CFU/g in the bruised samples, and further to 9.15x105 to 1.71x106 CFU/g in spoiled samples. Similarly, sweet potatoes exhibited THB counts from 4.15x105 to 6.35x105 CFU/g in healthy samples, 3.8x105 to 4.55x105 CFU/g in bruised samples, and 1.49x106 to 2.24x106 CFU/g in spoilt samples. Staphylococcus counts followed a similar trend in both potato types, with higher counts observed in bruised and spoilt samples compared to healthy ones. Total coliform counts also showed consistent increases in bruised and spoiled potatoes compared to healthy ones. Total fungal counts varied across all potato samples. Eleven bacterial genera and several predominant fungal isolates were identified through morphological and biochemical characterization including Enterobacter spp. 5.4%; Lactobacillus spp. 4.3% Micrococcus spp. 3.0% ,Klebsiella spp. 8.6%; Proteus spp. 8.9%; Pseudomonas spp. 8.6% Citrobacter 4.3%; Corynebacterium 5.4%; Staphylococcus spp. 20.4%; Bacillus spp. 20.4%; Escherichia coli 10.6%;; Yeast 26.5%; Aspergillus niger 20.4%; Mucor 20.4%; Fusarium 18.4%; Pink Yeast 6.1%; Aspergillus flavus 4.1%; Rhizopus stolonifera 2.0% and Trichoderma 2.0% . Nutritional analysis revealed differences in various nutritional components between healthy and bruised potatoes. These findings highlight the dynamic microbial interactions and nutritional changes occurring during potato spoilage, emphasizing the importance of improved storage and handling practices to maintain potato quality and safety.
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