Fermented chicken feathers using Bacillus subtilis to improve the quality of nutrition as a fish feed material

Chicken feather meals constitutes 80-85% protein, the main component being beta-keratin, a fibrous and insoluble structural protein extensively cross linked by disulfide bonds. The keratins can not be absorbed directly in the digestive system, therefore a processing technique is required to make it more absorbable. Processing technique can be fermentation by microorganism Bacillus subtilis to degrade keratin by secretion of keratinase. The aim of this study was to examine fermentation of chicken feather meal with B. subtilis to improve the quality of fish feed ingredients. The treatments were: no-fermented; fermentation of chicken feather meals: 6, 8, 10, 12 and 14 ml inoculum fermentation using B. subtilis, respectively for chicken feather meal as much as 2 g. The results showed that the processing fermentation with 10 ml inoculum B. subtilis gives the best results in the highest keratinase activity (273.33 U/ml), increased the protein content of chicken feather meals (74.16 to 85.20%), but decreated of lipid content (2.44 to 1.42%) and carbohydrate content (7.86 to 2.05%) with a change in the physical properties of white -yellow (color), soft (texture), and less typical sting (smell).