Abstract

Walnuts (Tetracarpidium conophorum) are globally recommended for their several health benefits. Here, we report on the geohelminths and bacteria associated with the cooked walnut shells. Cooked unshelled walnuts were purchased from Mile III Market in Port Harcourt, Nigeria in the month of September 2023, and examined for geohelminth and bacterial contamination using standard techniques. Geohelminths were identified using standard keys while bacteria were identified using their characteristics observed from morphological and biochemical tests. Isolated bacteria were also enumerated and calculated using appropriate formula. One geohelminth species (Strongyloides stercoralis) was encountered. Counts of total heterotrophic bacteria was 1.50×10⁶CFU/g; total coliform was 2.00×10⁴; faecal coliform was 1.30×10⁴, Salmonella/Shigella was 8.9×10³; and Staphylococcus species was 1.7×10³CFU/g. Bacterial species of the following genera were identified; Bacillus, Staphylococcus, Salmonella, Shigella, Pseudomonas, Enterobacter, Escherichia, Micrococcus, Acinetobacter and Klebsiella. Walnuts are commonly sold in a cooked, unshelled state. The presence of the geohelminth and bacterial species on the shells entails health concerns in persons cracking the shells in their teeth. It is hence, suggested that cooked, unshelled walnuts should be washed in saline water before cracking and consumption.