Determination of Ash Content

Experiment (6)

Determination of ash content

Aim: To determine the ash content in 5 samples of milk

Principle:
This experiment wills comparison between all samples. We will weight three times. First type the weight of crucible. The second is crucible and the sample the last about the weight of ash after removing from furnace.

Apparatus: 1. clean crucibles 2. Analytical balance 3. Clean tongs 4. Tripod 5. Bunsen burner 6. Silica triangle

Instruments: 1. Furnace

Procedure: 1. Clean crucible was placed in a blue flam in clean silica triangle 2. After it was warm the flam was raised briefly to red heat. 3. The crucible was cleaned and dried so must be handled with clean tongs and should be placed only on clean surface. 4. The crucible was allowed to cool for 2 min then transferred to a clean 400 cm3 beaker using clean tongs. 5. The crucible (W1) was weighed accurately. 6. 5ml of milk was introduced into crucible and weighed as (W2) 7. The crucible was placed in furnace for 7 hours at 600º C and then it was weighed as (W3).

Results:

|Type of milk |W1 (g) |W2 (g) |W3 (g) |% |
|Sohar |65 |70 |65.7 |6.6% |
|Nadec |65.3 |70.3 |65.5 |7.3% |
|Al Marai |61.4 |66.6 |61.5 |8.1% |
|A'Safwah |65.2 |72.5 |69 |5.3% |
|Al Rawabi |61.4 |66.2 |61.63 |7.4% |

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Calculation: To calculate the percentage of the ash we use this equation:

W2 - W3
Ash (%)