Determination of Crude Ash

1. Principle Ash is determined gravimetrically as the residue after incineration at 550 °C. 2. Scope This procedure is applicable for determination of ash in feed ingredients and feeds. This method cannot be used for mineral mixtures. 3. Responsibilities Laboratory Analysts shall perform the analysis as per this method. It is the responsibility of the Laboratory Analyst to ensure that all conditions laid down in the method are met and strictly adhered to. Any deviations from the prescribed method shall be recorded and supervisor notified. 4. Equipment 4.1 Incineration dish. 4.2 Analytical electronic balance, accurate to 0.1 mg. 4.3 Muffle Furnace, capable of maintaining temperatures to 550 ± 20 °C. 4.4 Desiccator. 5. Reagents None. 6. Procedure 6.1 Dry incineration dish (4.1) at 103 °C for at least 2 hours, remove from oven and cool in a desiccator. 6.2 Weigh the empty dish (4.1) to the nearest 0.1 mg (W1). 6.3 Add approximately 5 g of sample to the dish and weigh to the nearest 0.1 mg (W2). 6.4 Place the dish in preheated muffle furnace at 550 ± 20 °C (4.3) for 3 hours. 6.5 Inspect visually if the residue is free from carbonaceous particles (see remark 9.1). 6.6 Transfer dish into a desiccator (4.4) and allow to cool to room temperature (approximately 45 minutes). 6.7 Weigh the dish to the nearest 0.1 mg (W3). 7. Calculation Percent Ash (% ASH): % ASH = (W3 – W1) x 100 / (W2 – W1) where, W1 = weight of empty dish (g), W2 = weight of the dish and sample (g), and W3 = weight of dish and residue after incineration (g).ze”>Laboratory Analysts shall perform the analysis as per this method. It is the responsibility

of the Laboratory Analyst to ensure that all conditions laid down in the method are met

and strictly adhered to. Any deviations from the prescribed method shall be recorded and

supervisor notified.

4. Equipment

4.1 Incineration dish.

4.2 Analytical electronic balance, accurate to 0.1 mg.

4.3 Muffle Furnace, capable of maintaining temperatures to 550 ± 20 °C.

4.4 Desiccator.

5. Reagents

None.

6. Procedure

6.1 Dry incineration dish (4.1) at 103 °C for at least 2 hours, remove from oven and cool

in a desiccator.

6.2 Weigh the empty dish (4.1) to the nearest 0.1 mg (W1).

6.3 Add approximately 5 g of sample to the dish and weigh to the nearest 0.1 mg (W2).

6.4 Place the dish in preheated muffle furnace at 550 ± 20 °C (4.3) for 3 hours.

6.5 Inspect visually if the residue is free from carbonaceous particles (see remark 9.1).

6.6 Transfer dish into a desiccator (4.4) and allow to cool to room temperature (approximately

45 minutes).

6.7 Weigh the dish to the nearest 0.1 mg (W3).

7. Calculation

Percent Ash (% ASH):

% ASH = (W3 – W1) x 100 / (W2 – W1)

where,

W1 = weight of empty dish (g),

W2 = weight of the dish and sample (g), and

W3 = weight of dish and residue after incineration (g).