- Butter: The fatty part of milk, separating as a soft. . .yellowish solid when milk or cream is agitated or churned.
- Margarine: A butterlike product made of refined vegetable oils, sometimes blended with animal fats, and emulsified, usually with water or milk.
Back in the late 1800s, analytical chemists and control authorities were concerned that chalk and potato starch was used to bulk out butter, increasing the quantity and boosting profits for the seller. After margarine appeared on the market, sellers would also try to sell margarine as if it was butter as well as mixing much cheaper margarine into the butter.
Take about one tea spoon full of melted sample of Butter with equal quantity of concentrated Hydrochloric acid in a stoppered test tube and add to it a pinch of sugar. Shake for one minute and let it for five minutes. Appearance of crimson colour in lower (acid) of Margarine.