Home Chemical Test How To Determine Crude Fat or Ether Extract Calculation?

How To Determine Crude Fat or Ether Extract Calculation?

Crude Fiber
Crude Fiber

Calculation of Ether Extract or Crude Fat is a very important test in the Feed Mill Quality Control Laboratory – Crude Fat or Ether Extract Test or EE Test. So let’s first find out-

What is Crude Fat?

The difference between fat and crude fat is that fat is a pure fat or lipid, while crude fat is a crude fat or lipid – which may contain some other ether dissolved ingredients.

The method by which fat is separated from samples is called ether extraction method. And in this method all the fat and fat soluble components present in the sample are dissolved in ether. And the fat obtained is called crude fat. This is because the ether, fats as well as some plant pigments, esters and aldehydes used in this method also dissolve. This is why it is called crude fat or unrefined fat, not direct fat. So,

Crude fat is the total fat and fat soluble components present in a sample. It is also called Free Lipid Contents. So let’s learn how to test this crude fat or ether extract in the laboratory?

Lab Test – Crude Fat (Ether Extract)

Necessary equipment and chemicals
  • Samples
  • Blender machine
  • Analytical balance
  • Ether Extraction Apparatus (Succulents Apparatus) Machine
  • Fat flakes
  • Thimble
  • Cotton
  • Hot air oven
  • Desiccator
Necessary Chemicals

-N-Hexane or Petrolium Benzine – 200-250 ml

Crude Fat (Ether Extract) Test Method:

  1. The sample that we will test first should be well grinded in a blender machine and measured by the analytical balance of the sample like 1.5 – 2 grams on hotman paper or filter paper.
  2. Then the sample should be placed in the extractor of the distillation point of the succulents apparatus by closing the mouth of the thimble with cotton through the thimble.
  3. Then dry a round flax and take the weight. And the amount of hexane in it should be placed below the extractor at the distillation point.
  4. And leave the water line of the machine and switch on to distillation with heat for about 1 hour and 20 minutes.
  5. After distillation, open the condenser, collect the hexane and pour it. Gently open the bottle plug and keep the fat flakes in the oven at 135 degree Celsius for 30-45 minutes.
  6. Then cool in desiccant for 30 minutes. And will have to take the weight of the bottle again.
  7. The difference between the next weight and the previous weight is the crude fat.
  8. The amount of crude fat is then determined as a percentage from the amount of sample taken.
  9. Calculation: Crude Fat (Ether Extract) = {(Dry wt. With fat flask) – (Empty fat flask wt.) / Sample weight} x 100%

 (In the next article I  will discuss on  ” How to Determine Moisture Content? “)

Dr. Srabon Hasan Sajal


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