HAY-BOX AND SIMMERING PROCESSES OF PRESERVING
MILK—THEIR EFFECT ON GHEE PRODUCTION
By M. P. SRIVASTAVA, TECHNICAL ASSISTANT, JHALLAR CENTRE, H. NARASIMASWAMY, M.
R.
SRINIVASAN AND S. C. RAY, Indian Dairy Research Institute, Bangalore
(Received for publication on 5 June 1948)
(With one text figure)
M AJOR portion of ghee marketed in India comes from the villages. The quality of the product
and the economics of the ghee trade are linked closely with the regional rural practices in ghee
making. Since ghee is mainly obtained from surplus milk and as the holdings of the villager are
small, the morning and evening milk are generally pooled together for making measurable quantity
of ghee. In the Punjab villages, the usual practice is to give a form of heat treatment to the morning
milk so that it may remain sweet until the evening's surplus is added preparatory to curdling and
separation of butterfat. The form of heat treatment adopted by the villagers is to bring the morning
milk to boil and maintain it simmering the whole day. Cowdung cake is used as fuel which not
only entails the wastage of a valuable manure but the smoky flame it gives in an improperly designed
village hearth often contributes towards undesirable flavour in ghee and the by-product lassi.
The ' hay-box method of preserving milk hot ' as recommended by Read [1937] obviates the
defects observed in the village simmering process. The hay-box is a wooden box, the length and
breadth of which is about twice the greatest diameter of the milk pot and about ten inches more than
its height. The box is packed firmly, but not too tightly with bhusa, leaving just enough space
in the centre of the box for holding the milk vessel which may be a narrow-necked round-bottomed
earthenware goli. The operational part in the use of the hay-box consists in bringing the morning
milk, held in the earthen pot, to boil and as soon as possible the pot with its content is transferred in
the hay-box. More bhusa is then packed into the box all round the pot up to the edge of its neck.
The mouth of the pot is then closed with a wooden cap grooved inside the peripheral round so that it
can sit tightly over the rim of the pot and a layer of bhusa can be spread on top of it. After closing
the lid, the box is put out of the way until the evening. The thermal insulation secured by this
method preserves the milk fairly hot so that it can easily be transferred into the vessel containing the
evening milk for mixing and subsequent curdling.
As against continuous simmering, the hay-box method of preservation is undoubtedly capable of
bringing about considerable fuel economy. Read, however, claims that this method of preservation
effects a greater outturn in ghee by larger recovery of milkfat and also produces a better quality
ghee and lassi. In view of the importance of this claim, the Indian Council of Agricultural Research
had sponsored a scheme of investigation to ascertain the comparative merit of the hay-box method
against the customary simmering process. In the present communication are reported the results
of the experiments carried out at two centres, viz., Indian Dairy Research Institute, Bangalore and
Co-operative ghee Producers' Union, Jhallar, in the Central Provinces to throw light on the following
aspects :
(a) The relative merit of the methods of treatment on the preservation of milk.
(b) The effect of the methods of preservation on (i) the outturn of ghee, (ii) the market quality
of freshly prepared ghee and (iii) the storage life of ghee.
To include seasonal variation in the quality of milk the experiment at Bangalore was conducted
in (i) July August (early monsoon), (ii) October-November (late monsoon) and (iii) December-January
(winter) and at Jhallar in rainy and winter seasons.
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