Stability of sulphadimidine during raw fermented sausage preparation: reaction of sulphadimine with nitrite

 Raw fermented sausage was prepared from a dough to which sulphadimidine (SDM), a drug frequently used in animal husbandry, was added. With the aid of thermospray-mass spectroscopy further evidence was obtained that, during preparation, reactions with nitrite added to the dough resulted in the formation of desamino-SDM and 4-hydroxydesamino-SDM. An indication was obtained that traces of chlorodesamino-SDM were present in the brine, but this observation could not be established. Received: 22 March 1999 / Revised version: 10 May 1999     

Stability of sulphadimidine during raw fermented sausage preparation: reaction of sulphadimidine with nitrite

 In earlier studies of the stability of sulphadimidine (SDM) during the preparation of raw fermented sausage, some unknown reaction products were observed which have been further studied. Sausages prepared with SDM, and their corresponding brines were examined for the presence of desamino-SDM (DAS) and 4-hydroxy-desamino-SDM (SOH), as they are possible products of the reaction between SDM and the additive nitrite. After extraction, clean-up and solid-phase extraction (SPE) concentration, the compounds were identified by HPLC followed by diode array detection. The presence of SOH and DAS could be demonstrated in both sausage and brine. In sausage 2.5% of SDM was converted to DAS, while only a minor amount (0.1%) was transformed to SOH. In brine approximately 2.5% and 4% of the original amount of SDM was found as DAS and SOH, respectively. Received: 5 May 1997 / Revised version: 4 July 1997     

Stability of sulphadimidine during raw fermented sausage preparation: reaction of sulphadimidine with nitrite

 In earlier studies of the stability of sulphadimidine (SDM) during the preparation of raw fermented sausage, some unknown reaction products were observed which have been further studied. Sausages prepared with SDM, and their corresponding brines were examined for the presence of desamino-SDM (DAS) and 4-hydroxy-desamino-SDM (SOH), as they are possible products of the reaction between SDM and the additive nitrite. After extraction, clean-up and solid-phase extraction (SPE) concentration, the compounds were identified by HPLC followed by diode array detection. The presence of SOH and DAS could be demonstrated in both sausage and brine. In sausage 2.5% of SDM was converted to DAS, while only a minor amount (0.1%) was transformed to SOH. In brine approximately 2.5% and 4% of the original amount of SDM was found as DAS and SOH, respectively. Received: 5 May 1997 / Revised version: 4 July 1997     

Binding of sulphadimidine to glucose in sausage

 The presence of an adduct of sulphadimidine with glucose, i.e. N⁴-glucopyranosyl-sulphadimidine, was demonstrated in raw fermented sausage and batter to which sulphadimidine was added. Identification was performed by HPLC followed by diode array detection. This study demonstrates the need for a hydrolysis step prior to the determination of sulphadimidine for inspection purposes, in food samples containing glucose. Received: 21 October 1998     

Inhibition of Listeria monocytogenes and Escherichia coli O157:H7 in liquid broth medium and during processing of fermented sausage using autochthonous starter cultures

The antimicrobial effect of two autochthonous starter cultures of Lactobacillus sakei was evaluated in vitro (in liquid broth medium) and in situ assays. The inactivation of foodborne pathogens Listeria monocytogenes (serotype 4ab No 10) and Escherichia coli O157:H7 ATCC 43888 was investigated during the production of fermented sausage according to a typical Greek recipe using L. sakei strains as starter cultures. The inactivation kinetics were modeled using GInaFiT, a freeware tool to assess microbial survival curves. By the end of the ripening period, the inhibition of L. monocytogenes was significant in treatments with L. sakei 8416 and L. sakei 4413 compared to the control treatment. A 2.2-log reduction of the population of E. coli O157:H7 resulted from the autochthonous starter culture L. sakei 4413 during sausage processing. The use of the autochthonous starter cultures constitutes an additional improvement to the microbial safety by reducing foodborne pathogens.