The Microflora of Poorly Cleansed Farm Dairy Equipment

S ummary . A series of 170 rinses and 14 milk residue deposits from poorly cleansed dairy equipment on 136 farms, giving colony counts at 30° of > 10 6 /ft 2 for rinses or /g wet wt for residues, were classified into 8 groups according to the composition and milk spoilage activity of their microflora. Five of the groups were dominated by active milk spoilage types of bacteria and three by inactive organisms. Micrococci, coryneform bacteria and aerobic sporeforming rods dominated the microflora of 1/3 of the 184 samples. Gram negative rods, including coli‐aerogenes organisms, were dominant in another 1/3, a combination of micrococci, coryneform bacteria and Gram negative rods constituted the microflora of 19% and streptococci were dominant in 10%. Active milk spoilage types of bacteria were predominant in 106 (58%) of the rinses and deposits, but inactive types forming no reaction in litmus milk in 72 h at 22° were dominant in 78 (42%).