Microbial Quality and Internal Spoilage Assessment of Persea americana (Avocado pear) Sold at Oba, and Ochanja Markets, in Anambra State, Nigeria.
Keywords:
Persea americana, spoilage, assessment, quality, Anambra StateAbstract
Persea americana (Avocado pear) fruits are often lost postharvest due to microbial spoilage, with internal decay frequently remaining undetected until the fruit is cut. There is limited recent data, especially under local market conditions on the microbial contamination and internal spoilage status of avocados postharvest. This study evaluated the microbial quality and internal spoilage characteristics of Persea americana (avocado) fruits obtained from Oba and Ochanja markets in Anambra, Nigeria. A total of four (4) spoiled fruits were purchased from Oba and Ochanja markets and were transported in a sterile container, to the laboratory for microbial analysis. Standard microbiological methods were used to enumerate total viable counts (TVC), yeasts and molds. TVC were carried out using pour-plate technique. Detection of yeasts and moulds were carried using microscopic examination. Biochemical characteristics of the isolated organisms were determined using catalase, coagulase, oxidase, motility, sugar fermentation, indole, methyl red(MR), Voges proskuar and citrate tests. Results showed that total bacterial count ranged between1.1 ×103 and 4.7 × 104, with OBM 2 having the highest count, while OBM 1 had the least. Escherichi coli (E. coli ) spp and Salmonella spp were not detected in any of the samples. The total yeast count ranged between 1.1 × 103 and 3.5 × 102. The total mould count ranged between 3.2 x 102 and 4.7 × 104. Microorganisms isolated in this study include: Staphylococcus sp., Streptococci sp. Mucor sp., Saccharomyces sp. and Geotichum sp. Internal browning was the predominant defect. Firmness decreased significantly with increasing spoilage. Overall, the study shows that poor postharvest handling and sanitation in open markets contribute to elevated microbial contamination and high spoilage incidence in avocados. The results highlight the need for improved storage, reduced handling, and better hygienic practices along the supply chain to enhance fruit quality, extend shelf life, and reduce economic losses.
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