Investigation of microflora od autochtonous fermented sausages

Fermented sausages have a long tradition of production in certain regions of the world. For two years, research has been conducted under the EU sponsorship (FP5 "Safety of traditional fermented sausages: Research on protective cultures and bacteriocins") in the countries of west and southeast Europe (Greece, Bosnia and Herzegovina, Croatia, Hungary, Italy, Serbia and Montenegro). The first phase of research included the separation of lactobacilli and micrococci from the natural microflora of dry sausages during various stages of maturation. The investigation included fermented sausages produced in the countries of west and southeast Europe. The sausages were produced in local meat industries in a traditional way without the use of starter cultures. Their composition and parameters of maturation differed and were characteristic to the mode of production of traditional sausages in each member country of the research team. Samples were collected from three production batches on day 0 and again after 2, 4, 7, 14 and 28 days. Microbiological analysis included the principal ingredients (meat, fat tissue), casings and additives (sugar, spice mixture, salt), and finished products. It included the determination of total bacteria count, and the count of lactobacilli, micrococci, enterobacteria, enterococci, yeasts and moulds, in addition to the presence of S. aureus, L. monocytogenes and Salmonella spp. in 25 g of sample, and Pseudomonas spp., sulphite-reducing clostridia and the aerobic sporogenic bacteria count. From all three production batches of fermented sausages from each individual country were isolated 150 strains of lactobacilli and 150 strains of catalase-positive cocci, members of the family Micrococcaceae. Biochemical characteristics of the isolated microorganisms were determined by API-system (BioMerieux), i.e. by API 50 CHL and API® ; Staph. Identification of all strains was made using the computer program APILAB Plus. From the hygienic standpoint, it is highly important that L. monocytogenes, Salmonella spp. and S. Aureus were not found in the finished product. The number of other microorganisms in the course of fermentation, if present in the raw material or sausage stuffing, decreased. During all stages of investigation, lactobacilli and micrococci prevailed. These microorganisms are responsible for the formation of favourable organoleptic properties during maturation of dry sausages. Among the population of lactobacilli prevailed the strains Lb. sakei and Lb. curvatus. In addition, the following strains were isolated: Lb. plantarum, Lb. alimentarius, Lb. pentosus, Lb. rhamnosus, Lb. paracasei, Lb. brevis, Lb. plantarum/paraplantarum, Lb. fermentum, Lb. salivarius, Lb. bavaricus, Lb. acidophilus, Lb. maltoromicus, Lb. yamanashiensis, Lb. Delbrueckii, Lb. sanfrancisco, Lb. confosus, Lb. halotolerans, Lb. fructivorans, Lb. yamashienis, then Leuconostoc mesenteroides, Ln. paramesenteroides, Ln. lactis, Ln. citreum, Ln. oenos, and several strains of the genus Pediococcus. Most often, the isolated micrococci belonged to the genera Staphylococcus xylosus and S. saprophyticus. Furthermore, S. simulans, S. haemolyticus, S. caprae, S. capitis, S. sciuri, S. hominis, S. auricularis, S. warneri, S. cohni, S. epidermidis, S. carnosus, S. lentus and Micrococcus spp. were also isolated.