Steaming is a method of cooking

Cooking

Cooking is the process of preparing food by use of heat. Cooking techniques and ingredients vary widely across the world, reflecting unique environmental, economic, and cultural traditions. Cooks themselves also vary widely in skill and training...

 using steam

Steam

Steam is the technical term for water vapor, the gaseous phase of water, which is formed when water boils. In common language it is often used to refer to the visible mist of water droplets formed as this water vapor condenses in the presence of cooler air...

. Steaming is considered a healthy cooking technique and capable of cooking almost all kinds of food.

Method

Steaming works by boiling water continuously, causing it to vaporize into steam; the steam then carries heat to the nearby food, thus cooking the food. The food is kept separate from the boiling water but has direct contact with the steam, resulting in a moist texture to the food. This differs from double boiling, in which contact with steam is undesired.

Such cooking is most often done by placing the food into a steamer, which is typically a circular container made of metal or bamboo. The steamer usually has a lid that is placed on the top of the container during cooking to allow the steam to cook the food. When a steamer is unavailable, a wok

Wok

A wok is a versatile round-bottomed cooking vessel originating in China. It is used especially in East and Southeast Asia.Woks are most often used for stir frying, but can also be used in other Chinese cooking techniques, such as in steaming, deep frying, braising, stewing, smoking, or making soup...

 filled less than half with water is a replacement by placing a metal frame made of stainless steel

Stainless steel

In metallurgy, stainless steel, also known as inox steel or inox from French "inoxydable", is defined as a steel alloy with a minimum of 10.5 or 11% chromium content by mass....

 in the middle of the wok. Some modern home microwave ovens include the structure to cook food by steam vapor produced in a separate water container, providing a similar result to being cooked by fire.

Benefits

Overcooking or burning food is easily avoided when steaming it. Health conscious individuals may prefer steaming to other methods which require cooking oil, resulting in lower fat content. Steaming also results in a more nutritious food than boiling because fewer nutrients are leached away into the water, which is usually discarded. A 2007 USDA comparison between steaming and boiling vegetables shows the most affected nutrients are folic acid

Folic acid

Folic acid and folate , as well as pteroyl-L-glutamic acid, pteroyl-L-glutamate, and pteroylmonoglutamic acid are forms of the water-soluble vitamin B9...

 and vitamin C

Vitamin C

Vitamin C or L-ascorbic acid or L-ascorbate is an essential nutrient for humans and certain other animal species. In living organisms ascorbate acts as an antioxidant by protecting the body against oxidative stress...

. When compared to raw consumption, steaming reduces folic acid by 15%, and boiling reduces it by 35%. Steaming reduces vitamin C by 15%, and boiling reduces it by 25%. Phenolic

Polyphenol

Polyphenols are a structural class of natural, synthetic, and semisynthetic organic chemicals characterized by the presence of large multiples of phenol structural units...

 compounds with antioxidant properties have been found to retain significantly better through steaming than through boiling or microwaving. Most other nutrients are reduced by a similar amount by both methods of cooking.

Food by steaming

In Western cooking, steaming is most often used to cook vegetables - it is rarely used to cook meats. In Chinese cuisine

Chinese cuisine

Chinese cuisine is any of several styles originating in the regions of China, some of which have become highly popular in other parts of the world – from Asia to the Americas, Australia, Western Europe and Southern Africa...

, vegetables are mostly stir fried

Stir frying

Stir frying is an umbrella term used to describe two Chinese cooking techniques for preparing food in a wok: chǎo and bào . The term stir-fry was introduced into the English language by Buwei Yang Chao, in her book How to Cook and Eat in Chinese, to describe the chǎo technique...

 or blanched and seldom steamed. Seafood and meat dishes are steamed. For example: steamed whole fish

Fish

Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...

, steamed crab

Crab

True crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" , or where the reduced abdomen is entirely hidden under the thorax...

, steamed pork spare ribs, steamed ground

Ground meat

Ground meat is meat finely chopped by a meat grinder or a chopping knife. It is called minced meat or more usually mince outside North America....

 pork

Pork

Pork is the culinary name for meat from the domestic pig , which is eaten in many countries. It is one of the most commonly consumed meats worldwide, with evidence of pig husbandry dating back to 5000 BC....

 or beef

Beef

Beef is the culinary name for meat from bovines, especially domestic cattle. Beef can be harvested from cows, bulls, heifers or steers. It is one of the principal meats used in the cuisine of the Middle East , Australia, Argentina, Brazil, Europe and the United States, and is also important in...

, steamed chicken

Chicken

The chicken is a domesticated fowl, a subspecies of the Red Junglefowl. As one of the most common and widespread domestic animals, and with a population of more than 24 billion in 2003, there are more chickens in the world than any other species of bird...

, steamed goose

Goose

The word goose is the English name for a group of waterfowl, belonging to the family Anatidae. This family also includes swans, most of which are larger than true geese, and ducks, which are smaller....

, etc. Other than meat dishes, rice

Rice

Rice is the seed of the monocot plants Oryza sativa or Oryza glaberrima . As a cereal grain, it is the most important staple food for a large part of the world's human population, especially in East Asia, Southeast Asia, South Asia, the Middle East, and the West Indies...

 can be steamed too, although in Chinese this is rarely referred to as "steaming" but rather simply as "cooking." Wheat

Wheat

Wheat is a cereal grain, originally from the Levant region of the Near East, but now cultivated worldwide. In 2007 world production of wheat was 607 million tons, making it the third most-produced cereal after maize and rice...

 foods are steamed as well. Examples include buns

Mantou

Mantou, often referred to as Chinese steamed bun/bread, is a kind of steamed bun originating in China. They are typically eaten as a staple in northern parts of China where wheat, rather than rice, is grown. They are made with milled wheat flour, water and leavening agents...

, Chinese steamed cakes etc. Steamed meat dishes (except fish and some dim sum

Dim sum

Dim sum refers to a style of Chinese food prepared as small bite-sized or individual portions of food traditionally served in small steamer baskets or on small plates...

) are less common in Chinese restaurants than in traditional home cooking because meats usually require longer cooking times to steam than to stir fry. Commercially sold frozen food

Frozen food

Freezing food preserves it from the time it is prepared to the time it is eaten. Since early times, farmers, fishermen, and trappers have preserved their game and produce in unheated buildings during the winter season. Freezing food slows down decomposition by turning water to ice, making it...

s (such as dim sum) used to have instructions to reheat by steaming, until the rise in popularity of home microwave ovens which have considerably shorter cooking times.