Assessment of Microbiological Quality and Safety during the Processing of Traditional Beers made from Sorghum in the “Mandara” Mountains of the Far-North Region of Cameroon

Abstract

Indigenous beers are very popular and widely consumed by people from northern Cameroon because of its low cost. Despite their appeal, microbial quality of these beverages remains a serious call for concern. This work was aimed to investigate microbial changes and hazards of contamination during the processing of two special sorghum beers brewed in northern Cameroon. Producers were observed during the production and samples were collected at different stages for analysis of microbiological parameters such as total count, fungi, spore-forming bacteria, Coliforms and E. coli using referenced methods. Total count ranged from 13.5 x 103 to 195 x 103 CFU/mL and 0.16 x 103 to 660 x 103 CFU/mL; fungi from 0.26 x 103 to 22 x 103 CFU/mL and 0.22 x 103 to 85 x 103 CFU/mL; E. coli from 0.69 x 102 to 13.6 x 102 CFU/mL and 0.65 x 102 to 3.8 x 102 CFU/mL during the production of the red “té” and white “mepdli” beers, respectively. Spore-forming bacteria and Coliforms (total and fecal) were detected in all the collected samples. Bacterial spores were also enumerated in red (38 x 103 CFU/g) and white (62.5 x 103 CFU/g) sorghum grains used as the main raw materials for the production of “té” and “mpedli” beers. The results suggest that the processing of both turbid beers using the traditional method are exposed to microbial contamination. Increase of microbial loads after soaking, adding of the supernatant (red beer only) and malted flour (white beer only) after the heating step means that control measures are needed to prevent contamination after these sensitive stages. Proper handling of raw materials, adequate implementation of heating and fermentation were found as effective critical control points. Training of producers on the hazards analysis and good manufacturing and hygiene practices have been suggested as strategies to improve the safety of indigenous beers.