Gastric acid network (called canaliculi) from which the hydrochloric acid is secreted into the lumen of the stomach. The pH of gastric acid is 1.5 to 3.5 in the human stomach lumen, the acidity being maintained by the proton pump H/K ATPase. The parietal cell releases bicarbonate into the bloodstream in the process, which causes a temporary rise of pH in the blood, known as an alkaline tide. The highly acidic environment in the stomach lumen causes proteins from food to lose their characteristic folded structure (or denature). This exposes the protein's peptide bonds. The gastric chief cells of the stomach secrete
Erythorbic acid uptake or clearance from the body was found. A later study found that erythorbic acid is a potent enhancer of nonheme-iron absorption. Since the U.S. Food and Drug Administration banned the use of sulfites as a preservative in foods intended to be eaten fresh (such as salad bar ingredients), the use of erythorbic acid as a food preservative has increased. It is also used as a preservative in cured meats and frozen vegetables. It was first synthesized in 1933 by the German chemists Kurt Maurer and Bruno Schiedt. Erythorbic acid Erythorbic acid (isoascorbic acid, -araboascorbic acid) is a stereoisomer of