PASTEURISATION OF MILK FOR CHEDDAR CHBESE-MAKING. 295 
Pasteurised milk may be easily reinfected with undesir- 
able bacteria by careless clearing of the cooler, pipe con- 
nections, pump, vats etc. R.S. Smith’ and H. F. Judkins 
and P. A. Down! have drawn attention to the reinfection 
brought about by coolers. The latter investigators, in 
working with market milk, found an average increase of 
3,664 bacteria per c.c. due to milk passing over a cooler, 
while a pump and pipe added 11,755 bacteria per c.c.; in 
this investigation the cooler and pipe line probably received 
average or better attention. Judkins and Down add 
that the use of chloride of lime solution in flushing out 
all equipment before processing milk was found to do 
away with practically all recontamination of milk after 
pasteurising. 
Counts have been made of the fluid left in the bottom of 
vats and in the receiving trays under coolers. The lowest 
number of micro-organisms per c.c. was 563,000 and the 
highest 3,270,000. With summer conditions prevailing the 
numbers would be greatly increased and the proportion of 
harmful bacteria probably higher than in winter. 
Pasteurisation and the Vitamine Content of Cheese. 
Notes .on the quality of a dairy product are not complete 
without information being given as to its vitamine content. 
Recent research has shown the exceptional nature of milk 
and many ofits products as suppliers of vitamines in human 
nutrition. Any process which reduces the vitamine value 
of a foodstuff is to that extent rendered undesirable. For- 
tunately, as the following excerpts will show, the vitamine 
content of cheese made from pasteurised milk is not likely 
to be different in any marked way from that of the raw 
milk product. 
The work of Steenbock, Boutwell, and Kent‘ indicates 
that the anti-xeropthalmic vitamine (‘‘A”’ or ‘‘fat-soluble 
A’’) is destroyed by heat in the absence of water, a con- 
