Provides not only meat and eggs but feathers as well. Chickens fall into several classifications. The broiler-fryer can weigh up to 3 1/2 pounds and is usually around 2 1/2 months old. These chickens, as the name implies, are best when broiled or fried. The more flavorful roasters have a higher fat content and therefore are perfect for roasting and rotisserie cooking. They usually range between 2 1/2 and 5 pounds and can be up to 8 months old. Stewing chickens (also called hens, boiling fowl and just plain fowl) usually range in age from 10 to 18 months and can weigh from 3 to 6 pounds. Their age makes them more flavorful but also less tender. Chicken is an excellent source of protein, and a good to fair source of niacin and iron. White meat and chicken without skin have fewer calories. Hydrolysis is a chemical reaction during which one or more water molecules are split into hydrogen and hydroxide ions, which may go on to participate in further reactions. It is the type of reaction that is used to break down certain polymers, especially those made by step-growth polymerization. Such polymer degradation is usually catalysed by either acid e.g. concentrated sulfuric acid (H2SO4) or alkali e.g. sodium hydroxide (NaOH) attack, often increasing with their strength or pH. Hydrolysis is distinct from hydration, where the hydrated molecule does not "lyse" (break into two new compounds). It should not be confused with hydrogenolysis, a reaction of hydrogen.