Author(s): SANTOS, S. S.; MEDEIROS, M. I. M.; SOUZA, V.; MELO, P. C.; ZAFALON, L. F.; VESCHI, J. L. A.; NADER FILHO, A.

Summary: Milk is aa highly nutritious food and excellent substrate for the multiplication of microorganisms. The objective of this study wastoinvestigate the presence and formation of biofilm of Staphylococci before andafter the cleaning process in a micro-dairy plant in Sao Paulo State. Atotal of 60swab samples were collected before and after the cleaning process from the reception tank surfaces, the raw milkstorage tank, the pasteurizer outlet pipe, the pasteurized milk storage tank, and thefilling machine. Further samples were collected of the milk in the receiving tank, the rawmilk storage tank, from the pasteurizer outlet pipe, and packaged milk, as well as the empty sealed plastic packaging used for packaging the pasteurized milk. Of the 41 Staphylococcus spp strains, 39.0% indicated positive in the coagulase test, while 61.0% werenegative. Through genetic analysis, usingthe polymerase chain reaction technique, it was observed that within the 16 coagulase-positive strains, 25% presented the gene icaA and 100% hadthegene icaD. Of the 25 coagulase-negative strains, 44% hadthe gene icaA and 100% hadthe gene icaD. It was seen using a scanning electron microscope the formation of biofilm for ali the isolated strains. Fromthe obtained results it was possible tosee evidence tothe potential risk tothe health of the consumer represented by the presence of strains of Staphylococcus arising fromthecontaminated raw material or from deficiencies in hygienic cleaning, with formation of microorganisms' biofilms.

Publication year: 2012

Types of publication: Abstract in annals or event proceedings

Unit: Embrapa Semi-arid Region

Keywords: Biofilme, Biofilmes, Genes icaAD, Leite, Milk, Qualidade, Staphylococcus Aureus