Steam is water vapor that is created when drinking water molecules are suspended in the air due to the heat supplied to them. Vapor molecules carry large amounts of heat and return to their original shape (condense) when they come into contact with a cooler surface. When we talk about steam and its use in catering, the terms “heat” and “temperature” (sometimes used interchangeably) take on completely different meanings.
Amount of energy
Heat is the total amount of energy contained in steam or potable water at a given temperature. Temperature is used to describe how hot a given object is. It takes 180 Btus to heat 1 pound of water from freezing (32 degrees Fahrenheit) to boiling (212 degrees Fahrenheit). However, turning that same pound of water into steam requires an additional 790 Btus . This means that steam contains about six times the power of boiling drinking water.
The vapor temperature is generally related to its voltage. In short, the hotter the vapor, the greater its load. The higher its load, the more vapor molecules it contains. When these molecules condense, most of the Btus they contain are quickly transferred to the food being cooked, and the condensation makes room in the airspace for even more vapor molecules to replace those just condensed, in a cycle that continues until the heat supply goes down or is switched off.
Simple, clean and fast, steam has been around longer than electricity or gas as a heat source. In the hospitality industry, steam is used extensively in the dishwashing area to heat drinking water and to disinfect and dry dishes. When it comes to Dampfanlage cooking, steaming really is a healthy alternative to stovetop cooking that is nutritious and quick to do.
Most meals could be cooked in a steamer with three key benefits: greater control over food quality; less energy consumption than other types of cooking appliances; and minimal handling, as food could often be prepared, cooked, and served in the same pan. Steam is also a a much more efficient way to thaw frozen meals rather than submerging them in boiling drinking water. Steam is really an important part of these popular kitchen appliances:
The steam jacketed kettle is actually a large “bowl within a bowl” used to make sauces, soups and broths. The kettle has a robust outer layer. Between the two bowls is an area about two inches wide into which steam is pumped, providing high but even cooking temperatures. The drinking water used to generate steam can be heated either with gas or electricity.
A steamer is actually a rectangular oven-like appliance with an insulated door that can be used to steam vegetables, stew meat, boil rice, thaw frozen foods — anything that would benefit from the addition of moisture to the warm one , moist air circulates for faster and much more even cooking.
Often seen in cafeterias or on serving lines, steam tables hold food above a reservoir of warm drinking water to keep it warm. also a bain marie is a hot water bath in which an urn with sauce or a fine sauce is dipped, also to keep it warm. Steam systems and devices work in one of 3 ways:
- Steam generators use electricity to heat drinking water and generate their own steam. Small generators called boilers could be placed right in the kitchen under or near the steamer.
2. Heat exchangers take steam already generated from one source, circulate it through a series of coils to clean it, and use it to heat another source. For example, the steam from a building’s heating system could be captured by a heat exchanger and “recycled” and then used to heat the hot water tanks of that very same building.
- Steam injectors shoot pressurized steam directly into a device to generate heat. This is the least effective way to use steam as it is a one-time use. Condensed water is drained, not reheated and reused. The drive for water and energy savings has led to the development of boilerless steamers, also known as no-hookup steamers.
These are not supplied with drinking water; Water is added to them as needed, and they use it very efficiently—only 10 percent of the potable water that a traditional plumbed-in steamer uses. This means the difference between 8 or 10 gallons per day versus 30 gallons per hour. They won’t cook as quickly as traditional steamers, but unless you’re preparing large batches of product in a short amount of time, a plug-in steamer will more than meet your steaming needs, and perhaps save enough on water and electricity bills that the unit can fit into one annual amortization.
Today’s boilerless models can also be put on standby to save energy when not in use. Steam devices can be further classified into pressurized and non-pressurized devices.
Pressure steamers cook food quickly simply because the steam can become superheated and come into direct contact with the food. Pressureless steamers are not as efficient.