Microbial safety and quality of edible oil examined at Ethiopian public health institute, Addis Ababa, Ethiopia: a retrospective study

Abstract

Background: Nowadays food safety is considered to be one of the most global public health concerns. Edible oil is one of the most popular types of food to be consumed in every Ethiopian house. Though, its safety is not emphasized. It is produced in Ethiopia from small scale production to large industry level and / or imported from other countries. Objective: To evaluate microbial and hygienic quality of edible oil. Methods: A six year retrospective study design was conducted from January 2010 to January 2015 on 125 edible oil samples which were examined at Ethiopian public health institute, food safety and public health microbiology research laboratory, Addis Ababa, Ethiopia. The data was extracted using developed format from a laboratory registration book. Edible oil samples were examined for the presence of yeast, mould, aerobic plate count, total coliforms, fecal coliforms and Escherichia coli (E.coli). Additionally, examination for the presence of pathogenic organisms like salmonella species, shigella species, and staphylococcus aureus (S. aureus) were also performed. Data was cleaned and entered to Microsoft XL and then exported to SPSS for statistical analysis and values of different parameters were expressed as the mean±standard error (±S.E). Results: One hundred twenty five edible oil samples were examined among which 62(48%) samples were containing a varying number of bacteria and/or Moulds. Results given in Table1 shows that the aerobic plate count was detected in 46(35.6%), moulds 32(24.8%), Yeasts 4(3.1%), total coliforms 6(4.5%) samples. Fecal coliforms, E.coli and S.aureus were found only in one sample. None of the examined edible oil samples contain salmonella and shigella organisms. Conclusion: Some isolated microorganism indicates unhygienic condition of the edible oil somewhere in its way from processing to packaging and market display. The average microbial load is not higher than 105cfu/ml for Aerobic mesophillic bacteria and 104cfu/ml for moulds. These concentrations may be able to cause health problems in individuals who consume without enough heat processing and also some of the food spoilage organisms, specially the moulds, can hasten the deterioration the edible oil.