Benzyl-isothiocyanate (BITC) decreases quality of egg white proteins in rats

Isothiocyanates (ITC) are breakdown products of glucosinolates, which occur in some cruciferous vegetables. They have a high reactivity with the amino and sulfhydryl groups of proteins to produce thiourea derivatives and dithiocarbamate esters. Egg white proteins were treated with benzyl-ITC (BITC) and tested by protein quality rat bioassay. BITC reduced the lysine content of the treated egg white protein as well as lysine availability and also affected significantly the bioutilization of nitrogen and the deposition of energy. Supplementation of the damaged egg white protein with lysine alone enhanced the nitrogen retention almost to about 90% relative to the untreated proteins.