The influence of sulfonamides residues in milk on fermentation ability of yogurt culture

Abstract

In addition to the toxicological significance of residues of veterinary drugs in food of animal origin, the technological aspect is of great economic importance. The control of technological safety of milk is necessary due to variously sensitivity of certain starter culture to residual quantities of veterinary drugs. Sulfonamides, which are applied in the therapy of various illnesses in cows during lactation period, consequently lead to presence of residues of sulfonamides in milk. The annual production of joghurt in Serbia is estimated on 25.000 t, and therefore it is necessary to ensure about 5.000 t of starter cultures. These data clearly pointed out the economic aspect of the presence of antimicrobials in milk, due to their inhibitory effect on starter culture activity. The results of present study showed that certain quantities of sulfonamides are excreted by milk after intrauterine and intramammary therapy and consequently inhibited the activity of starter culture. At intrauterine application of antimicrobial drugs, inhibition of joghurt culture acidification depends on degree of disturbation in milk gland. At intramammary application of sulfonamides, the residues of sulfonamides could inhibit the acidification ability of joghurt culture during 16 milking.

Pored toksikološkog rizika, koji mogu prouzrokovati rezidualne količine veterinarskih lekova prisutne u namirnicama, značajna je i tehnološka sigurnost. Potreba za kontrolom tehnološke sigurnosti mleka proizlazi i iz različite osetljivosti pojedinih starter kultura na prisutne rezidualne količine veterinarskih lekova. Sulfopreparati koji se koriste u terapiji različitih oboljenja, tokom perioda laktacije kod krava dovode do nalaza rezidua sulfopreparata i u mleku. Polazeći od činjenice da se u Srbiji godišnje proizvede 250.000 t jogurta, potrebe za starter kulturama u tom slučaju iznose 5.000 t (tehničke maje). Ovi podaci jasno pokazuju kolike mogu biti ekonomske štete ukoliko se u mleku naðu materije koje inhibiraju rast starter kultura. Rezultati koji su prikazani u ovome radu jasno ukazuju da se odreðene količine sulfo preparata izlučuju mlekom posle intrauterine i intramamarne aplikacije i inhibiraju aktivnost jogurtne kulture. Pri intrauterinoj aplikaciji inhibicija kiseljenja jogurtne kulture zavisi od stepena promena u mlečnoj žlezdi, a pri intramamarnoj aplikaciji rezidue sulfopreparata mogu inhibirati kiseljenje jogurtne kulture tokom 16 muža.