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A number of food poisoning and enteric fever outbreaks throughout the country in 1955
resulted in the incrimination of imported egg products contaminated with salmonellae as the
causative factor, and bacteriological examination on an extensive scale not only confirmed that
this imported food was indeed a highly potential source of food poisoning organisms and also
of paratyphoid bacilli causing the more serious enteric fever, but drew attention to the fact that
other items of food might also be similarly contaminated. It is clear that hen's eggs are occasionally
infected with salmonellae and even one contaminated egg amongst thousands will spread
contamination throughout large volumes of the broken out liquid product. Subsequent batches may
be contaminated and there may be a build-up of infection in the plant. Shipments are divided into
batches according to production factors at the plant. Condemnation is limited to contaminated
batches rather than to shipments.
The pasteurisation of liquid whole egg at 48°F for 2½ minutes successfully eliminates salmonella
and this is best done immediately after breaking out and before freezing. Otherwise whole
egg must be thawed, pasteurised and refrozen, which is a costly procedure.
It is hoped that legislation will be introduced early in 1963 to ensure the pasteurisation of
all imported and home-produced liquid whole egg.
The pasteurisation of liquid whole egg and yolk before spray-drying should protect these
products. Egg white needs further research before methods of pasteurisation are proved satisfactory
for heat-treatment in the liquid state.
For many years the pan-dried product resulting in flaked or crystal albumen has been heat
treated in the dried state at 130°F for approximately 9 days including warming up and cooling.
This treatment is satisfactory normally but has failed in the presence of heavy contamination ;
it is seldom satisfactory for spray-dried albumen.

In the case of this food, the rapid reduction of bacteriological contamination has completely
justified the controls imposed. Plate counts as high as 75 million per gram were found during
the initial survey, and the presence of coagulase-positive staphylococci of food poisoning strains
was commonly found.
Today plate counts not exceeding 500 per gram are the rule rather than the exception, and
great credit is due to the producers for the energetic approach to and rapid solution of the problem
with which they were confronted.
The figures quoted are insufficient to enable-reliable conclusions to be drawn but the trend
is unmistakable.
In addition to the sampling of the foods referred to, all new foods or foods from a new source
are checked as to bacteriological condition over a period sufficient to eliminate or incriminate
them as potential sources of food poisoning.
All this sampling serves to attain two main objectives, firstly to demonstrate the potentially
dangerous food and deal with it in such a way as to destroy the bacteria and thus render it
harmless, or if this is not practicable, to prevent its distribution as an article of foodeither by
destruction or allowing its use for purposes other than for food and with proper safeguards.
Secondly, the attention of the producers is directed to their unsatisfactory product and the
processing, handling, packaging and the method of transport used, in order that investigation may
trace the point at which contamination is introduced.
In some cases by strict observance of hygiene the contamination has been eliminated, in
others the problem appears difficult to solve.
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