Identification of genuine and fake coffee

The "coffee" here refers to the brown powdered solid drink of raw coffee beans after roasting and grinding. Common adulterants in coffee are chicory root powder, roasted ground grains, etc., or processed with other bean-shaped seeds instead of coffee beans.

Sensory organs

The coffee is brown and powdery, and the coffee has a special aroma due to Maillard reaction during roasting, while fake coffee has no or little such specific aroma.

Density

Put the coffee powder to be tested in the test tube, add saturated sodium oxide solution and shake. The aqueous solution of real coffee should be light amber, and all or almost all of the powder floats, on the contrary, if most of the powder settles at the bottom of the tube, and the aqueous solution is dark yellowish brown, it is a substitute for chicory, roasted grains and other substitutes.

Qualitative examination of chicory root powder

Take about 10 grams of coffee to be tested, boil with 25 ml of water for 5 minutes, add excess alkali or lead acetate solid, shake for about half a minute, stand, wait for clarification and observe. If the upper aqueous solution is clear and colorless, it is pure coffee, and if it produces color, it is proved to be mixed with chicory root powder.