Procedures
1. Rinse extraction beaker with petroleum ether, drain, dry in an oven at 102 oC for 30 min and cool in a desiccators. 2. Accurately weigh 2-5 g of sample into the thimble. 3. Insert the thimble in a Soxhlet extraction unit. Place the extraction beakers filled with petroleum ether in the extraction unit. Then, perform the extraction for 2-6 hours. 4. After finish the extraction, place the extraction beakers in an oven at 102ºC and dry the contents until a constant weight is reached (30min-1 h). 5. Cool the extraction beakers in a desiccator and weigh them. 6. Calculation
Crude Fat (%) = (W3 – W2) x 100 W1
where: W1 = Weight of sample W2 = Weight of dried empty flask W3 = Weight of dried flask with fat/oil