Amygdalin is a cyanoside, which is easily hydrolyzed by acid and enzyme. The aglycone α -hydroxyphenylacetonitrile obtained by hydrolysis is unstable and easily decomposed into benzaldehyde and hydrocyanic acid. Benzaldehyde has a special fragrance and is usually used as a method to identify amygdalin.

In addition, benzaldehyde can make trinitrophenol test paper turn brick red, and this reaction can also be used to identify the existence of amygdalin. Molish reaction refers to the reaction of furfural and its derivatives with α -naphthol to produce purple compounds. The principle is that carbonyl groups condense with phenols. Therefore, the reaction used to identify the existence of amygdalin is the Molish reaction.

Extended data:

The content of amygdalin in bitter almond is 20 ~ 30 times higher than that in sweet almond. Hydrocyanic acid is released under the action of enzymes and acids in digestive tract, and absorbed into blood through mucosa, causing a series of toxic reactions. Hydrocyanic acid is a poison in protoplasm, and cyanide ions can combine with iron in cytochrome oxidase, resulting in inactivation of respiratory enzymes, obstacle of oxygen utilization in tissues and cells, and hypoxia in tissues.

Amygdalin is widely found in the seeds of loquat, apricot, peach, green plum, bayberry and other plants. Health education should be strengthened, and bitter almonds should not be eaten. Almonds must be heated and hydrolyzed to form hydrocyanic acid during processing before they can be safely eaten.

Baidu Encyclopedia-Molish Reaction

Baidu encyclopedia-bitter almond