Microbiological profile of retail sliced dry sausages in Ethiopia

Sausage production in Ethiopia has only a recent history. Previously, dry sausages were produced mainly from pork and hence there was low consumer demand due to religious reasons in relation to pork eating. Currently, dry sausages (commonly known as mortadella) made from beef, veal and chicken are also made available to consumers and there is a growing consumer demand towards these products. These dry sausage products are usually maintained under refrigeration and sold as vacuum-packed cylindrical rolls in casings or as slices. They can be consumed either heated or cold. However, there is no any report regarding microbiological quality and safety of these products. In this study, the microbiological profile of retail sliced dry sausages (pork, veal and chicken) collected from different retail shops in Addis Ababa, Ethiopia was determined. Mean pH values of retail dry sausages ranged from 6.09 to 6.33 and moisture content values ranged from 35 to 41%. Mean microbial count values (log cfu/g) ranged from 4.87 to 5.18 (aerobic mesophilic bacteria, AMB), 2.02 to 2.50 (Enterobacteriaceae), 1.73 to 2.24 (coliforms), 2.46 to 3.04 (enterococci), 3.09 to 3.76 staphylococci, 5.31 to 5.68 (lactic acid bacteria) and 3.28 to 3.87 (for yeasts). The aerobic mesophilic bacterial flora of retail sliced dry sausages was dominated by Gram-positive organisms. Salmonella was isolated from two sausage samples. Spoilage of sliced dry sausages, after the vacuum package was opened, was detected within 3 to 4 days during aerobic storage at ambient temperature (22oC on average) and within 12 to 20 days at refrigeration storage (4oC). The storage conditions were intended to reflect what normally would happen in routine food handling in home kitchen environments and food service establishments. Generally, the majority of retail sliced dry sausages showed the presence of high microbial load, which indicated contamination during or after processing of the products.