Commercial oven types and how to match one to your menu

Ovens are usually the biggest single line in a kitchen equipment budget, and the decision gets made on price more often than on menu. That is backwards. The oven determines what you can produce, how many staff you need to produce it, and how consistent it is on a Tuesday versus a Saturday.

Start with what you are cooking.

Convection ovens

A fan circulates hot air around the cavity. Faster and more even than a static oven, works at a lower set temperature for the same result, and handles multiple trays at once.

This is the general purpose choice. Good for baking, roasting, reheating and holding. Not great for anything that needs moisture, because the moving air dries the surface.

Sizes run from a 4 tray benchtop up to a 20 tray floor standing unit. For a cafe doing pastries, quiches and tray bakes, a 6 tray convection oven covers most of the day.

The main limitation is protein. A convection oven will roast, but the yield on a large joint is noticeably worse than in a combi because there is no moisture to slow the surface drying.

Combi ovens

A combi runs three modes: dry convection, steam, and a combination of both with controlled humidity. That third mode is why they cost what they cost.

Being able to roast at 160 degrees with 30 percent humidity changes the result substantially. Yields on protein improve by around 10 to 15 percent against a dry convection oven, because the moist environment slows moisture loss from the surface. On a kitchen roasting 40kg of protein a week, that is a real number.

Combis also do things no other single oven does: steam vegetables, hold at precise low temperature, regenerate plated meals, proof dough, and cook sous vide style without a bath.

The catch is installation. A combi needs:

• A treated water supply, because scale destroys steam generators. Budget for a proper water treatment system, not a filter jug.
• A drain rated for near boiling discharge, with a tundish.
• Extraction above it, usually a condensing hood.
• Three phase power on most sizes.

Operators regularly get a quote for the oven and discover the install adds a substantial amount on top. Ask for the full installed cost up front.

There are boilerless combis that inject water directly onto a hot surface rather than running a steam generator. They cost less, descale more easily, and produce slightly less consistent steam. For most mid sized kitchens they are a sensible compromise.

Deck ovens

Stone or steel decks with heat from above and below, no fan. The thermal mass of the deck is the point: it puts a burst of heat into the base of the product, which is what gives bread its oven spring and pizza its base char.

If you are making bread or pizza seriously, nothing else does this. A convection oven makes acceptable pizza. A deck oven makes good pizza.

Decks are slow to heat and expensive to run if you are only using them intermittently, because you cannot turn them off between services without losing an hour to bring them back. For a venue baking all day, that thermal mass is an advantage. For a venue doing twelve pizzas on a Friday, it is not.

Check whether the decks are independently controlled. A two deck oven where both decks share a thermostat is far less useful than one where you can run bread on top and pizza below.

Rack ovens

A whole trolley of trays rolls in and rotates during the bake. Output is measured in trolleys per hour and these are bakery equipment, not restaurant equipment.

If you are producing more than about 300 units a day of a single baked product, a rack oven is the step up from stacked convection ovens. Below that, the floor space and the install cost do not justify it.

Gas or electric

Gas is usually cheaper to run per kilowatt hour of delivered heat, heats fast, and is what most chefs are used to. It needs a gas connection, a certified install, and greater extraction because combustion products go into the room.

Electric is simpler to install, more precise to control, and increasingly the default in shopping centre tenancies where gas is unavailable or prohibitively expensive to run in. Electric also plays better with induction on the rest of the line and with any future electrification commitment.

If you are comparing gas range ovens against electric on running cost, get your actual tariffs rather than using general figures. In Queensland the gap has narrowed considerably and in some tenancies with demand charges, gas still wins clearly.

Sizing and the tray standard

Commercial ovens are specified by tray capacity, usually in GN 1/1 (530 by 325mm) or bakery standard (600 by 400mm).

Decide which standard your kitchen runs on before you buy anything, because mixing them means you cannot move trays between your oven, your blast chiller and your shelving. Most Australian restaurant kitchens run GN. Most bakeries run 600 by 400.

Allow more capacity than your current peak. Ovens are the constraint that limits menu growth, and adding a second oven later means finding floor space and services that may not exist.

Before you order

Confirm the door swing and whether it can be reversed. Confirm the unit fits through the doorway with the door removed. Check the stacking kit if you are putting two ovens on top of each other, because not all models can be stacked.

Ask who services the brand in your city and what the typical response time is. An oven out of action closes a kitchen, and a brand with no local technician is a risk no price discount covers.