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Use of Dewaxed Shellac in
Fruits & Vegetables
Coating for Apples
Apples are
best preserved, in the absence of refrigeration, by coating their
skins with a solution of castor oil and Dewaxed Bleached Shellac in
Alcohol. This retards weight loss and damage by mould. The best
coating has the following composition.
| Castor Oil |
5-6 |
| Dewaxed Bleached Lac |
2.50-3.00 |
| Alcohol |
91.00-92.50 |
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Skin coating by dipping into emulsions of oil,
wax and shellac delays the onset of ripening changes and prolongs
the storage life. Skin coating with the above emulsions or alcoholic
solution increased the resistance of the skin to gaseous diffusion,
and thus greatly reduces the internal oxygen concentration,
increases the carbon dioxide concentration, reduces the respiration
rate and retards ripening changes such as yellowing.
Coating for Oranges
A protective coating for
oranges for prolonging their storage life is produced by either of
the following two compositions.
| Material |
I |
II |
| Carnauba Wax |
26 |
26 |
| Refined Sugar Cane Wax |
13 |
13 |
| Oleic Acid |
5 |
4 |
| Triethanolamine |
6 |
8 |
| Dewaxed Bleached Shellac |
40 |
40 |
| Ammonia |
10 |
10 |
| Sodium o-henyl phenate |
0.50 |
1 | This is used as an instant dip
aqueous emulsions.
Coating compositions for Fruits &
Vegetables
|
A |
B |
| Dewaxed Bleached Shellac |
100 parts |
Caustic soda |
6 parts |
| Triethanolamine |
20 parts |
Water |
1000 parts |
| Water |
1000 parts |
Paraffin wax |
164 parts |
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Carnauba was |
55 parts |
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Stearic acid |
42 parts |
A is prepared by dissolving the
triethanolamine in the water, raising the temperature of the
solution to about 160 f (71 c) and dissolving the shellac with
efficient stirring. B is prepared by dissolving the Caustic
Soda in the water, raising the temperature to about 200 f (93.3 c)
and adding with stirring a molten mixture of the paraffin and
carnauba waxes and Stearic acid at the same temperature. The
stirring is continued till the waxes are uniformly dispersed.
A and B are allowed to cool temperature separately and
then mixed with efficient stirring.
This is a concentrated
solution and contains about 8 percent of wax and 4 percent Dewaxed
Bleached Shellac. For use for the coating of fruits, vegetables
etc., It will have to be diluted to a shellac content of 1.2 to 1.5
per cent.
The diluted solution wets all fruits and vegetables
readily and may be applied by dipping or spraying. The coating dries
within two minutes.
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An alternative composition consists of
candelilla wax, paraffin, shellac, neutral soap and water.
The storage life of fruits and vegetables are also prolonged
by coating with an emulsion containing oils, waxes and Dewaxed
Bleached Shellac. A mixture of 1 part of a 20 percent alkaline
solution of shellac and 5 parts of the oil wax emulsion (1 percent
of non-volatiles of oleic acid soap as emulsifying agent) is
satisfactory. Alkyl naphthalene sulphonates may be used as spreading
agents on waxy fruits. |
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Preservative coating for fruits,
vegetables & eggs
Fruits, vegetables, eggs etc may
be protected against mould and other causes of decay even when
stored at a temperature of 35 c, by coating with an alcoholic
solution containing 4-11 percent rosin and 1-4 percent shellac.
| Alcohol (96%) |
1000 gram |
| Dewaxed Bleached Shellac |
50 parts |
| Gum Dammer |
35 parts |
The eggs, fruits etc should be cleaned and
dried, as to their exterior, and dipped into this varnish, which
dries rapidly and protects the coated articles from
air.
Water removable coating for food
products:
A self lustering, water removable coating for
natural food products has the following composition.
| Carnauba Wax |
30.00 gram |
| Triethanolamine |
2.70 gram |
| Oleic Acid |
3.30 gram |
| Sodium Hydroxide |
0.50 gram |
| Water |
2.60 gram |
| Bentonite |
0.30-2.60 gram |
| Dewaxed Bleached Shellac Solution |
60 ml |
The shellac solution for the above is prepared
by dissolving 1.5 lbs of Dewaxed Bleached Shellac in 1 gallon of
water containing 0.33 lbs Borax.
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