130
Indigenous Methods of Egg Preservation
rate of deterioration among the two sets of con-
trols are perhaps due to the experiments not being
carried out simultaneously as well as to variations
in individual egg quality. Between the two pre-
servatives there does not appear to be any out-
standing difference in efficiency.
Hence it appears that the preservation of eggs
in green neem or shisham leaves, under the condi-
tions of this test, is not only of no advantage but
even of positive disadvantage.
Rice husk, salt and wood charcoal
Fertile and infertile eggs in equal proportions
were used in the tests with rice husk, salt and
wood charcoal. The maximum temperature and
relative humidity during the period of these experi-
ments averaged about 87°F. and 75 per cent,
respectively. Owing to the high temperature
prevalent in the egg storage room all fertile eggs,
whether preserved or not, developed prominent
blood rings by the fifth day of storage on account
of embryo development. Owing to this develop-
ment all of them had become inedible. At
the end of ten days of storage, conditions were
naturally considerably worse, the contents of
some eggs having actually started to rot, owing,
presumably, to the death of the germ. There was,
however, no case of mouldiness in any of the
different sets of preserved eggs, owing to the fact
that the storage materials contained insufficient
humidity for the development of moulds.
Figures for changes in interior quality set out
in Table II refer only to infertile eggs as all fertile
ones were spoilt by embryo development. A
study of the data in this table shows that preserva-
tion in rice husk, salt and wood charcoal resulted
in percentage declines from the original level of
33.3, 30.4 and 29.2 in five days and 42.4, 46.4
and 49.0 in ten days, respectively. With the
corresponding sets of control eggs for the above
three materials, the percentage deteriorations
recorded were 34.4, 34.1 and 35.5 in five days
and 49.9, 50.6 and 51.7 in ten days, respectively.
TABLE II
Changes in yolk indices of eggs preserved in rice
husk, salt and wood charcoal
Preservative
Rice husk . .
Period
of
storage
(days)
0
(Initial
quality)
5
10
Yolk index
Control
0.427
0.280
0.214
Preserved
0.427
0.285
0.246
Preservative
Salt . . .
Wood charcoal .
Period
of
storage
(days)
0
(Initial
quality)
5
10
0
(Initial
quality)
5
10
Yolk index
Control
0.405
0.267
0.200
0.439
0.283
0.212
Preserved
0.405
0.282
0.217
0.439
0.311
0.224
The rates of decline in quality as judged by
measurement of the yolk index were very similar
in all the control eggs. With the use of preserva-
tives, the lowest percentage decline in quality at
five days was recorded in the eggs preserved in
the wood charcoal and the greatest decline in the
eggs stored in rice husk. At ten days, the lowest
percentage decline in quality was observed in the
eggs stored in rice husk and the highest decline in
the eggs stored in wood charcoal. However,
though the rates of decline both at five and ten
days were slightly less in the preserved than in the
control eggs, the differences were relatively small
and were not significant. With these three pre-
servatives, there were no harmful effects resulting
from mould development.
Linseed oil
The investigation with linseed oil lasted for five
weeks. With this material also both fertile and
infertile eggs were tested. Fertile eggs were kept
as controls only for two weeks (since it was be-
lieved that they could not last longer without
spoiling) after which only infertiles were employed.
In the oil-treated group, both fertile and infertile
eggs were tested for the full period of five weeks.
The actual behaviour of the fertile eggs stored for
the first two weeks fully justified the assumption
that such eggs could last no longer without spoil-
ing, since all such eggs were spoilt by the end of
the first week, consequent upon embryo develop-
ment.
Painting with linseed oil did not affect the rate
of embryo development. Since temperature and
humidity, the most important factors controlling
the development of the embryo, were favourable
(as may be seen from Table III), the results
obtained were to be expected.