Evaluation of microbiological quality of raw milk, sour milk and artisanal yoghurt from Ouagadougou, Burkina Faso

Abstract

The present study was undertaken to investigate the microbiological quality of milk and artisanal dairy products sold in Ouagadougou markets. Forty-five (45) samples of milk and dairy products including raw milk, sour milk and yoghurt were collected and analyzed for aerobic mesophilic bacteria (AMB), total coliforms (TC), thermotolerant coliforms (TTC), Staphylococcus aureus (S. aureus), lactic acid bacteria (LAB) and yeasts and moulds (YM). The coliforms bacteria were then purified and identified by using API 20E system. The mean values of TC, TTC, S. aureus LAB and YM in the raw milk were 8.95, 6.43, 6.21, 4.83, 8.01 and 4.78 log cfu mL-1 respectively, In sour milk they were 10.44, 5.62, 4.12, 6.98, 7.38 and 3.75 log cfu mL-1 respectively, while in yoghurt samples the mean values of TC, TTC, S. aureus LAB and YM were 9.98, 5.77, 5.50, 6.12, 9.78 and 4.86 log cfu mL-1 respectively. The dominant coliforms isolated from raw milk, sour milk and yoghurt samples were found to be Escherichia coli, Klebsiella pneumonia and Enterobacter cloacae. Citrobacter spp was not found in any of the analyzed samples. The wide range of the samples analyzed did not comply with the standards quality. Thus it is necessary to set up an awareness program including capacity building of all the actors working in the sector of milk and dairy products. Key words: Raw milk, sour milk, yoghurt, microbiological quality, Ouagadougou.