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It cannot be treated by heat and still retain its designation. If bottled at the place of production
the words " Farm Bottled " may be added to the designation.
(c) Pasteurised, Milk is milk which has been pasteurised by being heated to a temperature
of between 140°F and l50°F for at least 30 minutes and then immediately cooled to a temperature
of not more than 55°F.
It will be noted that there are therefore now six designations applicable to milk, and these,
together with details of the bacteriological standards prescribed by the new order, are as
follows: —
Designation. Bacteriological standard.
1. Tuberculin Tested Milk This milk must not; decolourise
2. Tuberculin Tested Milk methylene blue within 4½ hours if the
(certified). sample is taken between 1st May and
3. Accredited Milk 31st October, or within 5½ hours if
4. Accredited Milk (Farm taken between 1st November and
bottled) 30th April. It must not contain B.
Coli in 1/100th millilitre.
5. Tuberculin Tested Milk Must not contain more than 30,000
(Pasteurised). bacteria per millilitre.
G. Pasteurised Milk Must not contain more than 100,000
bacteria per millilitre.
In addition to the bacterial plate count, the Ministry of Health recommend that the Phosphate
test should also be applied to milk which is sold under the designation "Pasteurised." By this
test, it is possible to detect even relatively small errors in pasteurisation technique. e.g. heating
the milk at 143°F instead of 145°F, or heating for 20 minutes instead of 30 minutes, or the addition
of as little as 0.3% of raw milk to the pasteurised bulk.
Several important changes are laid down in the new Order, and as will be observed from
the above, the plate count for raw milks is no longer recognised. Other amendments are (a) the
term "bottle" includes any container of a capacity not exceeding one quart and of a type
approved by the licensing authority; thus cartons may now be used for designated milks; (b)
the cap used for closing the bottle need not bear the day of production of the milk, and (c) the
licensing authority may dispense with the payment of licence fees.
During the year under review, 105 samples of graded milk, 27 of ungraded and 6 of raw
milk were purchased by the Sampling Officer for bacteriological examination. Forty-six of the
samples were purchased from milk vendors in the streets in the early hours of the morning and
44 were taken at the early morning delivery to the hospitals, etc., in the Borough which are
controlled by the London County Council.
Of the total of 138 samples examined 41 were especially tested by animal inoculation for the
presence of tubercle bacilli under Section 5 of the Milk and Dairies (Amendment) Act, 1922, and
in none of the samples so examined was tubercle bacilli detected.