Interest in healthier eating has boosted the use of steamers, but memories of water-related problems and dependability issues still dog the category. In response, manufacturers have come up with clever variations for generating steam and regulating temperature and pressure.
Connected or connectionless? All steamers started out tethered to a water supply line and wastewater drain. Eventually, hard water and scale buildup problems spurred the invention of the connectionless steamer—a device that’s able to generate steam inside the compartment bottom, not in a separate boiler or generator. Now manufacturers are marketing boilerless models that offer the best of both worlds: they retain in-compartment steam generation but feature water lines that eliminate the hassle of manually adding and draining water. New technology reduces water-related maintenance costs.
Pressure points Based on the model of your steamer, the steam in the cooking compartment can be under pressure (5-15 PSI), at atmospheric (or zero pressure) or even at reduced pressure (or under vacuum). The difference is the resulting temperature of that steam. By applying pressure at 5 lb. per square inch, steam reaches 230°F. Without applying any pressure, the steam registers 212°F, just like boiling water. But if the steamer uses a vacuum pump to remove air from the cooking compartment, water can boil and generate steam at less than atmospheric pressure and the temperature of the steam can go as low as 150°F. (The latest vacuum steamers have instant-open, vacuum-breaking doors.) While 230°F steam may cook faster, sub-212°F steam can baby heat-sensitive foods and hold foods without overcooking.
Water quality & treatment Water quality and effective water treatment remain important operator issues for all but the connectionless and boilerless steamer models. Virtually all U.S. water supplies are “hard” or contain significant levels of scale. This results in dissolved solids, not to mention potential suspended solids such as silt and bacteria. Effective water treatment is important for the proper operation, on-going cost and extended life of steamers—not to mention your operation’s icemakers, coffee makers and beverage dispensers. Water science and treatment options are complex. Seek help from local professionals in water analysis who can recommend treatment options. If a steamer does require regular deliming or descaling, be sure the process is safe and easy to do.