Fruits
Use of Dewaxed Shellac in Fruits & Vegetables
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 |
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.
This is used as an instant dip aqueous emulsions.
| 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 |
Coating compositions for Fruits & Vegetables
A rapid drying coating emulsion which may be applied to citrous fruits, melons and other fruits and vegetables to impart a pleasing glossy appearance as well as to retard their ageing is prepared of the following composition :
| A | B | ||
| Dewaxed Bleached Shellac | 100 parts | Caustic soda | 6 parts |
| Triethanolamine | 20 parts | Water | 1000 parts |
| Water | 1000 parts | Paraffin wax | 164 parts |
| Carnauba was | 55 parts | ||
| 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.
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.
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.