London's Pulse: Medical Officer of Health reports 1848-1972

View report page

City of London 1933

[Report of the Medical Officer of Health for Port of London]

This page requires JavaScript

49
wrappings or is contained in boxes or bags and is being discharged as fast as the facilities of the port permit,
while railway trucks and road vans are waiting to convey it to cold stores, markets or retail shops. The
policy in legislation regarding imported meat has therefore been first to prohibit absolutely certain classes
of meat such as scrap meat which, even if it is not derived from diseased animals is at least of very poor
quality, and meat from which serous membrane or lymphatic glands have been removed, the assumption
being that the object of such removal is to conceal disease; secondly to require evidence that the animals
from which the meat has been derived were examined ante-mortem and post-mortem by a competent
authority in the country of origin and were found to be free, from disease. Practically all imported meat is
now required to be accompanied by an official certificate which is defined as ' a certificate, label, mark,
stamp or other voucher which is affixed to oversea meat or to a package containing such meat by a competent
authority in the country of origin and is for the time being recognised by the Minister as evidence that the
meat to which it relates has been derived from an animal which was free from disease at the time of slaughter
and has been dressed or prepared and packed with all necessary precautions for the prevention of danger to
public health.'
"Though we are obliged to trust very largely to inspection in the country of origin, we are empowered
to examine any meat on its arrival in this country whether it is officially certificated or not. In the ordinary
way we are content to carry out such sampling as is possible without causing serious dislocation of the work
on the docks; in London we are in close touch with Smithfield Market, where the opportunities for inspection
are greater than in the port, and the Sanitary Authorities of inland districts inform us if unsatisfactory
conditions in imported food come under their notice. From time to time conditions have been discovered
which have necessitated much more thorough examination of certain imports, e.g., some years ago Australian
beef was subject to full inspection for the nodules in the brisket and the region of the stifle joint due to
the worm, Onchocerca gibsoni, and, more recently, every carcase of imported mutton was inspected for evidence
of caseous lymphadenitis. Frozen ox-tongues are always carefully watched for signs of actinobacillosis in
the submaxillary glands and the proportion of tongues examined is adjusted from time to time according to
the results of our inspection. Such rigorous measures on our part, however, are not usually necessary for
long. The particular problem is energetically tackled in the exporting countries, and we are able to reduce
our inspection to such sampling as is necessary to assure us that a high standard of examination is being
maintained abroad.
"There are no regulations prescribing the method of packing of refrigerated meat, but it is clear that
it is in the interests of merchants to arrange that such imports as offal, boneless meat, &c., shall be so packed
that inspection is possible without previous thawing of the goods. If boneless beef, kidneys, livers, &c.,
are frozen in a solid mass, it is quite impossible to carry out any inspection at all until the mass has been
throughly thawed out and separated into its component parts. This, of course, leads not only to delay, but
to deterioration of the meat. Again, where the Inspector will require to see serous membranes or particular
lymphatic glands, these should be made easily accessible.
"A number of recommendations have from time to time been made for the guidance of merchants;
for example, it is recommended that internal organs should be frozen separately, and be packed in layers not
more than two organs deep, so that at least one side of each organ is open to inspection without unpacking;
that the submaxillary glands of ox-tongues, and also in pigs, should be exposed to view on each side; that
pieces of boneless beef should be frozen separately before being bagged and that boneless veal should be
folded so that the pleura is exposed on one side and the peritoneum on the other.
"Official certificates too must be so placed that while they are protected from defacement or detachment
during transport they are readily accessible to the Food Inspector.
"The organisation and inspection in the abattoirs in the exporting countries is now so good that we
find very little disease in imported meat. The work of the Meat Inspector in ports is therefore principally
concerned with conditions which arise subsequent to the slaughter of the animals and the dressing of the
carcases, viz., brine staining, mould growths and decomposition. The most common of these conditions
in our experience is brine staining. Meat so affected is uneatable, and we therefore require it to be reconditioned.
This can be done by trimming when there is a good thickness of meat as on the legs and back of a
carcase of mutton. But where the interior of the thoracic or abdominal cavities is affected it is obvious that
efficient trimming is not practicable, and the affected parts must be condemned. Mould growths do not
make meat unfit for human food, but unless evidence of moulds is removed the meat is not marketable.
The most favourable conditions for the growth of moulds are a humid atmosphere and a temperature near
to freezing point. At lower temperatures moulds will survive and grow to some extent, but not rapidly.
Profuse growths of white moulds is evidence that at some stage of storage the temperature has been in the
neighbourhood of freezing point. White moulds can be wiped off, but black spot, which can grow at a
temperature as low as 18° F., requires trimming. At the present time there are arriving in this country
experimental shipments from Australia of chilled beef carried in an atmosphere containing about ten per cent.
of carbonic acid gas. This concentration of CO2 is sufficient to inhibit mould growths, and the condition of
recent consignments has been most encouraging. At the same time it appears that it is of the greatest
importance to avoid exposure of the meat to the spores of moulds before it is put on board ship. Nothing
can compensate for careless handling before shipment. Further, the greatest care is necessary in the
hanging of the meat in the chambers so that the cold air and CO2 gas circulate freely round every part.
I feel sure that with attention to detail in every stage from the abattoir to discharge from ship it will be
possible to land large quantities of chilled Australian beef in this country in excellent condition.
''Extensive decomposition of meat cargoes is now seldom seen, thanks to the perfection of refrigeration
machinery. Small quantities of meat which are soft and decomposed because of faulty stowage do
frequently come under the notice of Inspectors and are condemned. Bone-taint, which is a particular type
of decomposition, is now seldom met with, in the ports at least. I understand that the cause and prevention
of this condition are now well known.