Evaluation of Protein Deterioration of Dyed Wool Powdrs under Light Irradiation.

In order to establish the evaluation methods for the light stability of fur products, protein solubilities and amino acid compositions of dyed and un-dyed wool powders were examined after the irradiation of ultraviolet ray. The protein solubility of wool powders in M/20 sodium carbonate at 20°C for 2 h increased with irradiation time, corresponding to the protein deterioration caused by the irradiation. Such a deterioration was also evaluated with the decrease in the content of the half-cystine residue. Two parameters (protein solubility and the decrease in half-cystine) are considered to be adoptable as the indices of protein deterioration of dyed fur products under light irradiation.