The invention relates to a novel process for extracting collagen polypeptides from fish waste by high-valued and clean process steps. The process includes steps of extracting single-
helix collagens, removing fishy smell, deodorizing, performing
digestion, decoloring, desalting and spray-
drying. In detail, the process includes: cleaning
fish skin containing natural collagens having triple-
helix tight structures, draining off, adding
softened water, extracting for 3 h under controlled pH and temperature conditions, adjusting the pH value, adding diatomite, performing coarse
filtration to obtain coarse filtrate that is single-
helix fish skin collagens, subjecting the coarse filtrate to vacuum concentration, adding an
organic solvent, mixing and stirring for 1 h, allowing the mixture to stand, extracting, performing fishy-smell removing treatment and deodorizing treatment, adding an
enzyme mixture agent to perform
digestion, adding a decoloring agent, stirring for decoloring for 0.5 h while controlling temperature, filtering, desalting, and performing spray-
drying to obtain a white
fish skin collagen polypeptide product. The process is simple in steps, convenient in operation control, high in
utilization rate and good in
production quality.