SOP: Determination of Moisture in Salt

GIFSQ — Global Institute for Food Safety & Quality

1. Principle

The sample is dried to a constant weight at 250 ± 5°C and loss in weight is reported as moisture content.

2. Application

This method is applicable for determining moisture in sample having mineral origin, i.e. stable towards temperature.

3. Apparatus

Erlenmeyer flask, small funnel, temperature control oven.

4. Procedure

Weigh out dry empty 200 mL Erlenmeyer flask

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Weigh 10 g of sample in the flask

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Spread out the sample by shaking gently

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Insert small funnel in neck of the flask

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Place it in oven having temp. 250°C for one hour

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Cool, remove the funnel and weigh

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Again reheat, cool and weigh until two readings do not differ by more than 5 mg

5. Calculation

% Moisture = [Loss in weight ÷ Wt. of sample] × 100

6. Limit of Detection

This method is suitable for determining the moisture in sample stable towards heat. Measurement of loss in weight is appreciable in sample having more than one percent moisture.

7. Precautions

• Cooling of sample should be done by means of desiccator.
• Weighing should be carried out near about same temperature in every instance.

References

Rangana S. (1986), Handbook of analysis and quality control for fruit and vegetable products, 2nd edn, Page 205–206.