The cattery must be able to be closed off from the rest of the house. Many different methods of cooking exist across the country, and the structure and the materials used in constructing kitchens have varied depending on the region. Very few manufacturers produce home built-in kitchens from stainless-steel. Some architects have capitalized on this «object» aspect of the kitchen by designing freestanding «kitchen objects». However, like their precursor, Colani’s «kitchen satellite», such futuristic designs are exceptions. The astronauts’ food is generally completely prepared, dehydrated, and sealed in plastic pouches, and the kitchen is reduced to a rehydration and heating module.