Small molecular substance, molecular weight does not exceed 1000. In addition, the melting point of aspartic acid is above 230℃, there is no exact melting point, and the decomposition and release of CO 2 during melting; Can dissolve in strong acid and alkali solution; At room temperature, aspartic acid is slightly soluble in water, insoluble in ethanol and ether, and soluble in boiling water. It can be combined with acids to form salts, and it can be combined with bases to form salts. It can be seen from the structure of aspartic acid that it has optical activity due to the asymmetric carbon atoms in its molecules. At the same time, due to different spatial arrangement positions, aspartic acid, which is composed of proteins, is L-type.