Abstract:
In Ethiopia, it has been reported that there are no official quality control standards and cooling and other preservative facilities for most dairy products. Under such circumstances, fresh raw butter which has pleasant taste and odor will lose its quality because of microbial contamination. Hence, this study was conducted with the objective of investigating the butter preservation potential of selected spices/herbs commonly used in traditionally processed butter around Shashemenie town. For the study, raw butter samples were collected from 10 local households of the study area. Butter analysis for microbial contamination was conducted using dilution method and 1 ml of 10-5 was inoculated into plate count agar (PCA) for enumeration of bacterial contaminants and into potato dextrose agar (PDA) for the enumeration of yeasts and moulds. Isolation and identification of bacteria were conducted using selective media, gram staining and a series of biochemical tests. The results of microbial counts showed that both bacterial and mould counts were significantly (P<0.05) higher on non-spiced butter than on spiced ones. Identification of the isolates showed that butter spiced with ginger, garlic and cardamom did not support the growth of E. coli, Salmonella Typhi and Staphylococcus aureus as they showed negative results. Whereas spiced with sweet basil and fenugreek supported.The results of the antimicrobial activity tests showed that garlic at 200 mg/ml showed the highest inhibition zones of 18.3±0.3 mm, 18.0±0.9 and 18.0±0.5 against E. coli, Staphylococcus aureus and Salmonella Typhi, respectively. Generally, the five selected butter flavoring spices showed inhibition against butter contaminating bacterial and fungal microbes. Awareness creation on butter producers, retailers, and consumers on how to prevent butter from microbial contamination should be carried out by responsible agricultural bureaus
