Gelatin containing smaller ratio of large molecule portion like b-chains exhibited lower viscosity value. Gelatin prepared at a high citric acid (0.05 M) or HCl (0.07 M) concentration, or with weak acetic acid (0.01, 0.03 M) or HCl (0.01 M), had smaller ratio of b-chains and also lower viscosity; while gelatins made with acetic acid ranging from 0.05 M to 0.20 M had similar MW distributions and similar viscosity as well.