Three well packaged branded Kachchi ghani mustard oil bottles from the local store and were kept at the room temperature for testing.
4.3 METHODS AND MATERIALS
1) Moisture and volatile content
Aim: Determination of Moisture content of the mustard oil.
Apparatus: Moisture dish: made of aluminium sheet, Dessicator, Hot air oven
Procedure:
1. Dry and cool the moisture dish in the dessicator and then weigh it.
2. Weigh accurately about 10 g of the oil sample into the dish.
3. Place the dish in the air oven for one hour at 105 + 1 degree Celsius.
4. Remove the dish from the oven, cool it in the dessicator to room temperature and then weigh it.
5. Repeat this procedure until the difference between the two successive weighings does not exceed 1 mg.
Calculation:
Moisture and volatile matter content, = 100 w (Percent by weight) W

Where, w = loss of weight in g of the sample upon drying. W = weight in g of the sample taken for the test.

2) Pungency test Aim: Determination of allyl iso-thiocyanate i.e. Natural essential oil (Pungency Test)
Theory: The oil obtained from black mustard seeds contains sinigrin and myrosin which, after maceration with water yields a volatile oil, the major constituent of which is allyl iso-thiocyanate. The oil obtained from white mustard seeds contains acrinyl iso-thiocyanate which is much less volatile than allyl iso-thiocyanate. The presence of ally iso-thiocyanate is responsible for the pungent nature of