 Gastric acid is one of the main secretions of the stomach.It consists mainly of hydrochloric acid and acidifies the stomach content to a pH of 1 to 2.Chloride (Cl−) and hydrogen (H+) ions are secreted separately in the stomach fundus region at the top of the stomach by parietal cells of the gastric mucosa into a secretory network called canaliculi before it enters the stomach lumen.