Determination of % FAT
- SOXHLET EXTRACTION APPARATUS
- THIMBLES (should be kept in oven at 100oC)
- Weigh approximately 2 g of sample. Wrap sample up in kimwipe and place kimwipe inside thimble.
- Record weight to 4 decimal places.
- Place thimble in labeled beaker. Dry overnight at 100oC, reweigh immediately from oven and record weight to 4 decimals.
- Place thimble inside extraction unit.
- Fill boiling flask « to 2/3 full with hexane. (After cleaning flasks add a small amount of zinc metal to serve as boiling chips.)
- Turn on cooling water.
- Turn on heating units.
- Allow to extract for 6 h.
- Remove thimbles and place in beakers. Pour excess hexane into reserve jug.
- Place thimbles in oven at 100oC to dry overnight.
- Weigh immediately from oven. Record weight to 4 decimal places.
- Calculate fat % and record with one decimal.
- %FAT = ((wt. after drying) - (wt. after extraction)) x 100/(thimble and sample wt.) - (thimble wt.))
- Analyze AAFCO check sample along with each set.
- Horwitz, W. (ed). 1970. Official Methods of Analysis of the Association of Official Analytical Chemists, 11th Edition, Washington, D. C., p.128.