Steam-jacketed kettles can produce greater volumes with increased consistency, while reducing labor for both preparation and cleaning. Here is a quick overview of this type of foodservice equipment.
Steam-jacketed kettles utilize steam energy to transfer heat via conduction to the food product inside.
The energy source — electric, gas and direct steam — that operates the unit helps define the categories of kettles available to operators. Direct steam kettles offer greater efficiency, cooking the fastest with the highest capacity as compared with electric and gas models. Kettle sizes range from 5 to 200 gallons, although 40 gallons represent the most common size commercial foodservice operators tend to use.
Stationary floor models typically start with a 20-gallon capacity and go up from there. In contrast, the capacity for tilting floor-type kettles ranges from 20 to 200 gallons. Tabletop kettles accommodate between 1 quart and 12 gallons of product.
While some tilting kettles have a handle, larger models utilize a crank. Stationary kettles include a tangent draw off valve that opens to drain product from the vessel.
The operating pressures of these kettles range from 45 PSI to 50 PSI, which produces an even temperature from the entire jacketed surface of 267 degrees to 338 degrees F.
These units feature either 304 or 316 stainless steel construction. While 304 is designed for general purpose use, such as boiling pasta, the more durable 316 can be a better option if the foodservice operator will prepare highly acidic foods, like pasta sauce, in the kettle.
The majority of kettles are two-thirds jacketed, which means that the unit transfers heat energy not only from the bottom of the kettle, like in a stock pot on a range, but also from the sides. This dramatically increases the surface area for energy absorption into the product. Operators can also purchase fully-jacketed kettles.
Most kettles come with optional accessories as well as features that enhance the operation for specific applications, such as mixers, draw off valves, pan carriers and mixing faucets.
New steam-jacketed kettle features include solid state temperature control with self-diagnostic capabilities. A heat deflector shield can help protect staff from burns.
One manufacturer introduced a new line of two-third jacketed kettles with an improved bottom, which allows for a shallower design.
Energy Efficiency and Steam-Jacketed Kettles
Newer kettle technologies are more energy efficient and can save operators money over the long term.
Kettles are more energy efficient than alternate cooking methods, due to the transfer of steam energy via conduction and the increased surface area gained by the lined jacketed construction.
Additional options are available per individual manufacturers specifications for digital temperature read outs as well as food cooling in some instances.
Kettles also are available with better ergonomic designs for easier use.