Production of valuable materials by hydrothermal treatment of shrimp shells

The possibility of amino acids and glucosamine production from the treatment of shrimp shells in high-temperature and high-pressure water was investigated. Under the tested conditions, the highest amount of amino acids (70 mg/g of dry shrimp shell) from hydrolysis of proteins was obtained at a reaction temperature of 523 K in 60 min. This amount was about 2.5 times the total amino acids obtained at 363 K, the temperature at which shrimp extracts for use in noodles soup are being prepared. The amount of simple amino acids such as glycine and alanine increased with increasing temperature up to 523 K and decreased thereafter. This behavior has also been observed from other seafood processing wastes such as fish entrails and scallop wastes. Glucosamine was not detected presumably because of its deamination to produce glucose or cellulose. To further investigate the reason for the nonformation of glucosamine from shrimp shells, experiments on chitin as the starting reaction material were carried out.