T. S. KRISHNAN 129
measurements can be made is also considerably
widened. All yolk indices reported in this paper
have been determined by this procedure.
In some experiments only infertile eggs were
used while in others equal numbers of fertile and
infertile eggs were employed.
A daily record was kept of the maximum tem-
perature and relative humidity in the egg storage
room during the whole course of these trials.
EXPERIMENTAL RESULTS
Green neem and shisham leaves
In the experiments with these two materials,
infertile eggs only were used. As it is well known
that infertile eggs stand storage better than fertile
ones, it is reasonable to assume that the efficiency
of these preservatives would not be higher with
fertile eggs than with infertiles, and consequently
that the results of this test are the best obtainable
with these substances. The maximum daily
temperatures in the storage room during the period
of this investigation ranged from 95°F. at the
commencement to 87°F. at the end of the period
of experimentation. The relative humidity during
the same time ranged from 64 per cent to 80
per cent.
With the eggs preserved in green neem leaves
fermentation of the leaves was marked even on
the first day, the temperature rising to 102°F.
which was 7° above the room temperature. After
the second day the temperature began to fall and
at the end of five days, when eggs were removed
for analysis, the temperature had fallen to 97°F.
Similar but less marked changes were noticed in
the case of the eggs preserved in shisham leaves.
When eggs were taken out for examination after
five days, the leaves gave off a musty smell. The
exterior of the shells of the eggs preserved in both
materials were covered with dark spots which also
gave off a musty odour. When opened out, the
eggs preserved in neem leaves appeared to be
normal except for a slight smell of neem in some of
them but with shisham leaves half the number of
eggs tested were already spoilt by mould growth
and the rest had a slightly mouldy smell. Since
the leaves were mouldy in both cases the remain-
ing eggs were preserved in fresh lots of the res-
pective leaves for the next five days. Fermenta-
tion did not ensue but all the eggs in both groups
were completely spoilt by mould when examined
at the end of the second five days. This is pro-
bably due to the fact that all eggs had already
been infected with mould spores during the first
five days and merely keeping them in fresh leaves
could not arrest the growth of the mould.
The figures for interior quality as measured at
the different stages are given in Table I.
TABLE I
Changes in yolk index of eggs preserved in neem and
shisham leaves
Preservative
Neem leaves . .
Shisham leaves .
Period
of
storage
(days)
0
(Initial
quality)
5
10
0
(Initial
quality)
5
10
Yolk index
Control
0.400
0.280
0.197
0.411
0.309
0.229
Preserved
0.400
0.359
*
0.411
0.345
*
* Measurement of yolk index could not be made since all
eggs were spoilt by mould growth.
It may be seen from the above that preservation
in neem leaves resulted in the yolk index decreas-
ing from 0.400 to 0.359 in five days, indicating a
decline in quality of 10.3 per cent from the ori-
ginal level. During the same period the control
eggs showed a loss of 30 per cent from the initial
level. In the next five days, while the controls
declined by a further 20.8 per cent in quality, the
yolk index dropping to 0.197 from the initial
figure of 0.400, the preserved eggs were all spoilt
by mould growth. With shisham leaves similar
results were obtained. The decrease in quality
shown by eggs preserved in this material as well
as the corresponding controls during the first five
days was 16.1 per cent and 24.8 per cent res-
pectively from the starting level. At the end of
ten days all the preserved eggs were found to be
mouldy, while the controls still remained fit for
consumption though they had lost 44.3 per cent
of their initial quality, the yolk index having
declined from 0.411 to 0.229.
From the yolk-index figures it would appear
that the preservatives were of some value in
reducing the loss of yolk quality during the first
five days. However, as some of the eggs pre-
served in neem leaves smelt of neem and half of
those in the shisham leaves group had been spoilt
by mould growth within this period, it is apparent
that these defects more than counterbalance the
slightly better yolk-index figures obtained with
the two preservatives. At the end of ten days,
though all the preserved eggs were spoilt, the
controls, as judged by their broken-out appearance,
were all still edible. The small differences in the