H. C. VERMA, ZAL R. KOTHAVALLA AND E. V.
SESHACHARYULU
223
ACKNOWLEDGEMENT
The author is indebted to Dr P. V. Sukhatme,
Statistician to Imperial Council of Agricultural
Research, Prof. P. C. Mahalanabis, Messrs S.
Roy, P. Bose and J. Sen Gupta of Statistical
Institute, Calcutta, Mr P. C. Roy, Statistician
to Bengal Agricultural Department for help and
guidance on the statistical side, and his own
staff of the Animal Nutrition section specially
Messrs M. Rahman and Sayed Ali.
REFERENCE
Carbery, M., Chatterjee, I., and Hye, M.A. (1934). Indian
J. vet. Sci. 4, 29 5-340
Carbery, M., and Chatterjee, I. (1936). Indian J. vet,
Sci. 6, 87-99
STUDIES IN THE BACTERIOLOGICAL QUALITY OF MILK PRODUCED
AND HANDLED UNDER DIFFERENT CONDITIONS IN AN
INDIAN CITY (BANGALORE)
By H. C. VERMA, ZAL R. KOTHAVALLA and E. V. SESHACHARYULU, Imperial Dairy Research
Institute, Bangalore
(Received for publication on 16 December 1943)
ALL the world over, the hygienic quality of
market milk is as a rule assessed by its bacterio-
logical examination, the methods commonly
employed being the plate method for total
bacterial count, methylene blue reduction test
and presumptive coliform test. Extensive work
has been done on this subject by foreign workers
under their own conditions of supply and this
has enabled the milk controlling authorities
there to lay down different standards for the
bacteriological grading of market milk supplies.
This system of classification and control of the
milk supply has not only safeguarded the inter-
ests of the consumer but has prevented enor-
mous losses to the producer, distributor and
manufacturer through the milk going bad.
The quality control of market milk in India
today covers only its chemical aspect and aims
at checking its adulteration. The bacteriologi-
cal grading of milk is not in force. The condi-
tions of production, handling and distribution
being far from satisfactory, the milk industry
at present suffers an enormous loss through
souring and other causes and the consumer's
health may be greatly imperilled. The first
step considered necessary, to bring about an
improvement in the present state of affairs is
the obtaining of information on the bacteriologi-
cal quality of milk produced and handled under
conditions prevailing in this country. Only a
very limited amount of work on the subject has
so far been done. Joshi [1916] examined 68
samples of milk collected from city stables and
240 samples drawn at random from dairies,
cattle stables, milk hawkers and milk shops in
Bombay. He found that the former averaged
17.103.000 and the latter 36,385,000 bacteria
per ml.
Walton [1925, 1927] examined
samples of milk produced at the Pusa Agricul-
tural Research Institute Dairy and found that
the plate and coliform counts varied with the
season of the year, the highest found being
during the rainy season. The Imperial Dairy
Institute [1939] examined samples of milk pro-
duced and handled in its dairy and the results
showed that the average plate count per ml.
and methylene blue reduction time were
235,000 and four hours respectively.
While the work done so far is interesting,
it does not provide the material necessary for
defining the quality of milk offered for sale in
the Indian market on the basis of its bacteriolo-
gical condition. The work involved in obtaining
material of this kind must of necessity be diffi-
cult and considerable, due to various factors,
the chief amongst them being the vastness of
the country, the conservative methods of pro-
duction, handling and distribution of milk,
inadequate and difficult transport facilities and
the variety of climatic conditions prevailing all
over the country. It was therefore felt that
information on the quality of milk obtained
from different sources was a necessary prelude
to further work being done on the subject.
The work carried out under this investigation
was therefore undertaken. Throughout this
investigation the tests employed to determine
the bacteriological quality of milk were (a)
methylene blue reduction test and (b) the plate
count. The work was confined to the condi-
tions governing the supply of milk to Bangalore.
EXPERIMENTAL
The supply of milk to Bangalore is from
various sources. The milk sold is either that
of cow or buffalo or a mixture of both. The