Detection of Butter and Ghee Adulterations (Basic methods)

Butter is adulteration with Mutton, fat, beet, fat and different oils, potato pulp starch, Jaggery, soft paraffin’s, vegetable oil, hydrogenated fat and margin.

Coal tar dye : Melt the butter in a test tube kept in a hot water bath and continue heating until the fat and water layers completely separate out. Decant off the butter fat from the top into a clean dry test tube. In another test tube, dissolve about 2 mt of' clear fat in ether, add to it 1 to 2 ml of 50% hydrochloric acid, shake and allow to settle. Formation of a pink to wine red colour in the lower acid layer shows coal tar dye.

Vanaspati : Dissolve a pinch of cane sugar in 10 ml concentrated hydrochloric acid taken in a glass stoppered test tube. Add 10 ml of the melted ghee, stopper the bottle and shake vigorously for two minutes. Let it stand till 2 layers separate. If the lower layer turns pink or red, the ghee contains vanaspati.

Mashed potatoes, sweet potato and other starches: The presence of mashed potatoes and sweet potatoes in a sample of butter can easily be detected by adding a drop of tincture of iodine. Iodine which is brownish in color turns to blue if mashed potatoes / sweet potatoes / other starches are present.

Coloring Matter: Martinis Test. — Add 2 parts of carbon bisulfide, a little at a time and with frequent shaking, to 15 parts of alcohol. Shake 25 cc. of this solution with 5 grams of the butter, and let stand for some time. The carbon bisulfide dissolves out the fatty matter and settles to the bottom. The alcohol remains on top and will dissolve out any artificial colors that may be present. If only a little coloring matter is present use more of the butter.

Annatto: Evaporate a portion of the extract to dryness and add sulfuric acid to the residue. If annatto is present a greenish blue color forms. Should a pink tint result the presence of a coal-tar color is to be suspected.

Saffron: When saffron is present, nitric acid colors the alcoholic extract green, and hydrochloric acid colors it red.

Turmeric: Add ammonia to the alcoholic extract, and if it turns brown it indicates the presence of turmeric.

Marigold : Add silver nitrate to the extract, and if it turns black the presence of marigold is indicated.