Moist-heat cooking unlocks flavor and freshness

Up to Steam
Moist-heat cooking unlocks flavor and freshness

By Margaret Sheridan, Senior Editor

The principle behind steaming is simple: When water reaches its boiling point of 212F, steam—the gaseous state of water—is produced. Because of its form, steam has more heat energy than boiling water, making it a powerful and efficient way to cook.

There are many reasons to master the fine points of steaming. It is quick, cost- and labor-efficient and works for small-batch and high-volume cooking. Steam’s energy shortens cooking times, retains vitamins and enhances appearance of food. Colors remain bright. Because moisture in food is preserved, shapes stay intact. In the call for more healthful food choices, steaming is becoming more popular because no fat is needed, according to Peter King, chef-instructor in culinary arts at Johnson & Wales University, Providence, R.I.

“Steaming maintains the integrity of flavor in foods,’’ says King. Since it showcases flavors, good or bad, using the freshest ingredients is critical.

The cooking method also is an adjunct in food preparation, such as steaming raw vegetables for salads or garnishes, and can be used to reheat and refresh cooked foods. Steaming is the foundation of many dishes, such as New England clambake, fish en papillote, Asian-style dumplings, sweet and savory breads and puddings, tamales and Asian hotpots. Foods best suited include fish, vegetables, grains, poultry, rice, lean fish; shellfish and some fruits.

In high-volume cooking, steaming is used to pre-cook vegetables, rice and grains and frozen foods. At Sheraton Chicago Hotel & Towers, Chicago, a variety of steaming equipment is used to produce up to 2,700 meals per day, according to Executive Chef Bernhard Gotz. Steamer kettles hold rice, pasta, soups, chili and sauces. Cooked pasta is refreshed. Steaming, unlike immersion in boiling water, does not break down starches or make pasta soggy or sticky. Delicate foods such as cream-based sauces, soups and dairy-rich mashed potatoes are held easily in steamers without fear of scorching or burning. It minimizes cleanup and becomes a versatile workhorse in labor-tight kitchens, adds Gotz.

But not every operation or menu requires heavy-duty equipment. At the 100-seat Coco Pazzo Cafe, Chicago, Executive Chef Tony Priolo steams vegetables and whole fish in baskets and pots.

TECHNIQUE TIPS

1. Steam cooks by enveloping the food in a tightly sealed cooking vessel. Bringing water to a boil (212F) then trapping steam under a lid or cover is the critical first step. Food, arranged in a basket, a perforated pan or on a rack, is lowered over (although not into) boiling water. Steam’s heat energy is transferred when it comes in contact with a cooler surface, such as food. This can take place directly (in a steamer) or indirectly (through the wall of a steam-jacketed kettle, for example). Unlike other moist-heat methods such as boiling, poaching, simmering and braising, water never touches the food.
2. Steam needs to circulate freely so food must be arranged spaciously. Keep foods uniform in size to facilitate even cooking. Do not layer foods; steam in batches. In a set of stacked pots, the upper pot has a perforated bottom and is fitted over a larger pot of boiling or simmering water. Perforations allow steam to rise and penetrate. Temperature needs to be constant. When using steamer baskets instead of high-tech ovens, the level of boiling water must be watched and replenished as necessary.
3. When using steamer equipment, consult a manufacturer’s guide for cooking times, but adhere to basic cooking principles for each food. Check for doneness by looking for appropriate texture, color, consistency, shape and aroma. Steamed foods should be plump, moist and tender. Flesh of fish and shellfish will lose translucency and become opaque. Mollusks, such as clams and mussels, open when properly cooked. Vegetables will have good color and no graying. Grains will be fluffy and tender. Practice kitchen safety: Remember that steam is extremely hot. Protect hands and face when opening a door or raising a lid or cover.

Smart moves
To get the most from steaming, think smart.

Almost any liquid can be used for steaming, including stock, wine or bouillon. Herbs and spices may be added, but use caution. Some, such as mace, overpower flavors.
Each time more liquid is added to the pot, cooking temperature is lowered. Adjust cooking time accordingly.
Modify heat according to the nature of food being steamed. An intense or rolling boil can cook too fast, causing some delicate proteins such as fish fillets to contract.
If steaming is used as a preliminary cooking technique, heat only until food reaches a par-cooked state. Remove immediately and plunge into cold water to stop cooking.

Equipment
There is a steamer for every budget, menu and kitchen size. They range from simple tiered-bamboo or metal baskets (from $12 per set) to state-of-the-art ovens (from $7,000) that deliver multiple functions. Three of the most commonly used steamers are combi-ovens, convection steamers and steam-jacketed kettles. In each style, steam comes in direct contact with food. The door or lid can safely be opened during cooking to check and rotate food.

Combi-ovens offer multiple functions, a variety of temperature ranges and preset controls. They’re on the wish lists of many chefs though not always within their budgets. In addition to steaming and convection cooking, combi-ovens roast, bake, proof, reheat and brown.

In the dual-function steam/convection ovens, steam is generated in a boiler then piped to the cooking chamber where it is vented over food. They are common in high-volume food production and at those operations that rely heavily on frozen food. Circulating hot air flows during the convection cycle; steam is injected during steaming mode. Steam/ convection ovens come in a variety of models and styles, from single unit to double-stacked oven.

Steam-jacketed kettles offer versatility in floor or countertop models. Available in graduated capacities from 10 to 100 gallons, often with a tilt feature and manual crank, electronic ignition, hinged cover and pouring lip. Steam is circulated between walls of the kettle, providing even heat distribution. Some styles can be mounted into a cabinet or hot line.