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information as to the methods to be adopted for ensuring that their product
is of high bacteriological purity. No new premises should be registered
unless there are satisfactory arrangements for sterilisation. In a recent
investigation in the Manchester district* it was found that when "cold
mix" ice cream was made in the Laboratory for experimental purposes, its
bacterial content depended on the state of the milk, and, to a lesser extent,
on the purity of the ice cream powder. Polluted milk yielded polluted ice
cream; when the mix was heated, satisfactory samples were produced.
Storing for long periods—especially when the ice cream is already polluted
—and re-freezing may cause an enormous increase in the bacterial content.
The State of Michigan requires all mix to be dated and used within a week
of pasteurisation.
*The Bacterial Content of Ice Cream in relation to manufacture, storage and standard
of purity. Doris A. Bardsley. Journal of Hygiene, September, 1938.
Chemical Analyses.

It is generally agreed that if a chemical standard were adopted a
minimum fat content of 8 per cent. should be required.
In Hampstcad 50 per cent. of samples had less than 8 per cent. of fat,
indeed, in a third of the cases the figure was less than 4 per cent., while in
a quarter it was less than 3 per cent. All the samples were free from preservative.