The gastric juice contains HCl and proenzymes. The proenzyme pepsinogen, on exposure to HCl gets converted into the active enzyme pepsin which converts proteins into proteoses and peptones (peptides). The HCl provides an acidic medium (pH – 1.8) which is optimum for pepsin, kills bacteria and other harmful organisms and avoids putrifaction. So, if HCl is not secreted in stomatch, digestion of protein and destruction of harmful micro organisms will be affected.
