# Comparative Analysis of Microbial Load in Smoked and Fried Tilapia (Chambo) From Wholesale and Retail Markets

## TL;DR

This study compares the microbial contamination in smoked and fried tilapia from wholesale and retail markets in Malawi, finding higher contamination in retail samples.

## Contribution

The study provides new insights into microbial load differences between wholesale and retail fish markets in Malawi.

## Key findings

- Retailer fish samples showed significantly higher bacterial loads compared to wholesaler samples.
- Retail samples contained diverse bacteria like Escherichia coli and Pseudomonas putida.
- Smoked tilapia had higher bacterial counts than fried samples.

## Abstract

Fish, including Oreochromis shiranus (Chambo), is a vital protein source in Malawi, but consumption has declined. Due to its perishability, preservation methods like smoking and frying are common. This study compares the microbial load in smoked and fried tilapia from wholesale and retail markets. This cross‐sectional study compared the microbial load in smoked and fried tilapia (Chambo) from wholesale (Salima) and retail (Lilongwe) markets. Twenty fish samples (10 smoked and 10 fried) were collected, transported in sterile conditions, and analyzed for Total Aerobic Plate Count and coliforms using ISO‐standard methods. Data was log‐transformed and analyzed using two‐way analysis of variance, with significance set at p < 0.05. Fried tilapia from wholesalers had low levels of contamination, with most samples showing too few colonies to count, while some smoked samples displayed higher bacterial counts (33.75 ± 3.77 CFU/mL). Retailer samples showed a wider range of bacterial species, including Escherichia coli and Pseudomonas putida, suggesting potential hygiene concerns. Overall, bacterial loads were significantly higher in tilapia from retail markets compared with those from wholesalers (p < 0.05). The analysis showed higher microbial contamination in tilapia from retailers, with greater bacterial diversity, including E. coli, indicating poor hygiene. Wholesaler samples had minimal contamination. Although preservation methods showed no significant difference in microbial loads, retailer fish had significantly higher bacterial loads.

This study investigates microbial contamination in fish samples from wholesalers and retailers in Salima and Lilongwe, Malawi. Significant microbial growth, observed in retailers rather than wholesalers, highlights potential health risks associated with fish handling practices. Findings emphasize the need for improved food safety protocols to mitigate contamination and ensure public health.