SOP: Determination of Alcohol Soluble Extract — Spices
GIFSQ — Global Institute for Food Safety & Quality
1. Principle
Sample is extracted with ethanol and evaporated to dryness. It is heated in the oven at 103 ± 2°C; the remaining residue is alcohol soluble matter.
2. Application
This method is applicable to determine the amount of alcohol soluble material in spices under specified conditions.
3. Apparatus
- Oven at 103 ± 2°C
- Steam bath
- Desiccator, containing an efficient desiccant
4. Reagents
Ethanol 95% v/v
5. Procedure
Take 2 g sample with ethanol in a 100 mL volumetric flask
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Shake the stoppered flask at 30 min interval for about 8 hours
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Allow to stand 16 hours longer without shaking
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Filter and evaporate 50 mL to dryness
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Heat in the oven at 103 ± 2°C to constant mass
(Two final weighings should not differ by more than 0.002 g)
6. Calculation
Alcohol extract % = [(Wt. of residue × 2) ÷ Wt. of sample] × 100
7. Precautions
- Sample should be powdered and do not leave the flask without stopper.
- Evaporation should be carried out such that the residues do not turn black.
References
FSSAI (2016), Manual of method of analysis of foods — spices and condiments; Method no 7, Determination of Alcohol Soluble Extract.