Physicochemical, Hygienic & Others Indexes of Silk Peptide exterior light yellow powder dissolvability dissolved in water and< 40% ethanol total N %(W/W) ≥13.0 drying shrinkage %(W/W) ≤5.0 pH value 4.0-7.0 Hg mg/kg ≤1 Asmg/kg ≤5 Pbmg/kg ≤20 aerobic bacterial count, num/g ≤100 fecal coliforms, num/g nondetactable pseudomonas aeruginosa nondetactable staphylococcus aureus nondetactable Advantages Silk Peptide Silk peptide is a kind of silk proteinic product with smaller molecular weight consisted by a few or ten odd amino acids. Its molecular weight is generally between 300 to 2000 with better water soluble property but not dissolved in the high density ethanol or ether. Table 3. Physicochemical, Hygienic & Others Indexes of Silk Peptide Item Silk Peptide Powder exterior light yellow powder dissolvability dissolved in water and< 40% ethanol total N %(W/W) ≥13.0 drying shrinkage %(W/W) ≤5.0 pH value 4.0-7.0 Hg mg/kg ≤1 Asmg/kg ≤5 Pbmg/kg ≤20 aerobic bacterial count, num/g ≤100 fecal coliforms, num/g nondetactable pseudomonas aeruginosa nondetactable staphylococcus aureus nondetactable