Alkalies

Bases soluble in water — including the strongly basic hydroxides of sodium, potassium and ammonium — that neutralise acids and are neutralised by them, with solutions showing pH above 7. The food industry uses alkalies in processing, from lye peeling of potatoes, peaches and olives to nixtamalisation of maize with lime, which unlocks niacin and transforms flavour; alkaline noodles owe their springy bite to kansui. They also serve heavily in cleaning, where caustic solutions strip fats and proteins from equipment. Concentrated alkalies burn skin on contact, so food-grade handling demands respect for chemistry’s oldest reagents.