Vitamin C

Ascorbic acid — a water-soluble vitamin essential for collagen synthesis, wound healing, immune function, and iron absorption, and a powerful antioxidant. Vitamin C deficiency causes scurvy: bleeding gums, poor wound healing, and fatigue. Citrus fruits, berries, peppers, and potatoes are rich sources. It is notoriously fragile — destroyed by heat, oxygen, light, and alkaline conditions — so processing and storage losses are major; food scientists use vitamin C retention as a marker of overall nutrient preservation. Beyond nutrition, ascorbic acid serves as a food additive (E300): an antioxidant in cured meats (curing accelerator) and a dough conditioner in baking.