SOP: Test for the Presence of Vanaspati Ghee in Butter (Baudouin Test)

GIFSQ — Global Institute for Food Safety & Quality

Scope

This method is applicable for testing the presence of vanaspati ghee in butter and ghee.

1. Principle

The development of a permanent pink colour in a sample of butter with furfural solution in the presence of hydrochloric acid indicates the presence of sesame oil, and the test is known as the Baudouin test. (Vanaspati ghee is marked with sesame oil, so the test detects vanaspati adulteration through the sesame marker.)

2. Reagents

a. Hydrochloric acid (fuming): sp. gr. 1.19

b. Furfural solution: 2 percent solution of furfural in ethanol, distilled not earlier than 24 h prior to the test from rectified spirit

3. Procedure

Take 5 mL of the melted ghee in a 25 mL measuring cylinder provided with a glass stopper

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Add 5 mL of hydrochloric acid and 0.4 mL of furfural solution

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Insert the glass stopper and shake vigorously for 2 minutes; allow the mixture to separate

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The development of a pink or red colour in the acid layer indicates the presence of sesame oil

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Confirm by adding 5 mL of water and shaking again. If the colour in the acid layer persists, sesame oil is present. If the colour disappears, it is absent

References

Manual of Methods of Analysis of Foods, Milk and Milk Products, FSSAI, 2016; 13.6.