Control of bioflavour and safety in fermented sausages : first results of a European project

Four types of fermented sausages were prepared: two using Northern technology (Norway and Belgium) and two using Mediterranean technology (Belgium and Italy). Mediterranean sausages showed higher pH values and highest residual amounts of myosin and actin. Free fatty acid concentrations reflected the nature of the raw material, rather than the ripening period. Italian sausages contained the highest amounts of hexanal. Norwegian sausages contained the highest amounts of both free fatty acids and free amino acids. Putrescine concentration could be related to initial contamination of raw materials. Mediterranean sausages were characterised by a 'pop corn' odour, identified as 2-acetyl-1-pyrroline. Proteolytic activity of pork Triceps brachii was found to be related to animal sex. Staphylococci and lactic acid bacteria were investigated. Leucine metabolism involving aldehyde production was found to be strain specific and very sensitive to pH and the presence of nitrite. Bacteria showed anti-oxidant activity, enhanced by the presence of manganese. Bacteriocin production by L. casei CTC 494 was studied and results incorporated into a mathematical model. (C) 2000 Elsevier Science Ltd.