and biofilms in the dairy industry: effects of surface material, incubation temperature and milk type.

(. , . subsp. asachharedens, . and . ) and (two strains of . , . and . ) isolates and reference strains in whole milk were evaluated for their biofilm production on six different abiotic surfaces. DSM 465 had the highest cell counts (>4 log CFU cm) on glass and stainless steel (SS) at 55 and 65 °C, respectively. D195 had the highest counts on SS at 55 °C (>5 log CFU cm) and polyvinyl chloride (PVC) at 65 °C (>4 log CFU cm), indicating the existence of strain variation. The ideal surfaces for all strains were SS and glass at 55 °C, but their preferences were polystyrene and SS at 65 °C. Moreover, members were more prone to form biofilms in skim milk than in semi-skim and whole milk, whereas the results were the opposite for . Both the attachment and sporulation of in whole milk was higher than in semi-skim or skim milk. This study proposes that the surface material, temperature and milk type had a cumulative effect on biofilm formation.