Fungal and bacterial contaminants of six spices and spice products in Ghana

Abstract

The microbiological quality of two spices (aniseed and rosemary) and spice products (maggi onion cube, maggi shrimp cube, royco shrimp cube, royco beef cube) have been studied using conventional mycological techniques. The presence of moulds and yeast was compared on three media DRBC, OGYE, and PDA at 30°C incubated for 5 days. The species of fungi that were isolated from the raw spices and spice products tested belonged to eight (8) genera. (Absidia, Aspergillus, Cladosporium, Fusarium, Rhizopus, Penicillium, Neurospora, Eurotium,). Aspergillus species (A. flavus, A. fumigatus, A. alutaceus, A. niger, A. sulphureus) were the more predominant species isolated. A. flavus was the most frequently isolated fungal species in all the spices on all the three media on which growth was compared. Aniseed harboured fungal population ranging from 1.50 log₁₀ CFU/g sample to 1.88 log₁₀ sample; maggi onion cube 0.90 – 1.54 log₁₀ CFU/g sample; maggi shrimp cube 1.11 – 1.30 log₁₀ CFU/g sample; royco shrimp cube; 1.0 – 1.08 log₁₀ CFU/g sample and 1.19 – 1.31 log₁₀ CFU/g sample in royco beef cube. The aflatoxin analysis showed that aflatoxins B₁ , B₂, G₁,and G₂ were not formed. The bacteria species isolated from the spices varied. The spices and spice products collectively harboured Aeromonas salmonicida, Enterobacter cloacae, Enterobacter amnigenus, Enterobacter agglomerans, Enterobacter sakazakii, Flavobacterium sp, Chromobacterium violaceum, Pseudomonas putida, Pseudomonas aeroginosa, Acinetobacter sp, Pseudomonas cepacia, Serratia plymuthica. The human health implications of these findings are discussed and future work recommended.

Key words: Microbiological quality, spices, spice products, contaminants.