Sustainability in the Textile Sector: Wool Dyeing with Hydrolyzate from Black Soldier Fly

The textile industries mostly rely on synthetic dyes, which contain nonbiodegradable components and high toxicity, making their use environmentally hazardous. The present research delves into the unique application of proteins extracted from the Black Soldier Fly (BSF) as a natural dye for wool fabrics. The hydrolyzates extracted from each insect material (larvae, cocoons and flies) using superheated water at 170 °C for 1 h were used as natural dyes for dyeing wool fabrics with and without mordant (ferrous sulfate, 5% o.w.f.). Fabrics treated with mordant-free hydrolyzate derived from cocoons showed the best results, with an increase in color strength (K/S value) from 0.43 to 2.78 with an increasing dye concentration from 2% to 50% o.w.f. Color fastness to washing shows that dyed fabrics undergo variable color changes (from grade 4 to grade 1) but release little dye onto other fabrics, especially wool and synthetic fibers. Dry and wet rubbing color fastness tests showed overall variable color fastness, with little color loss on the abraded reference fabric. Overall, this work emphasizes the possible use of hydrolyzate from BSFs as a natural and environmentally friendly dye, which may represent a promising alternative to synthetic dyes in the textile industry.