Cooking ranges

The cooking range lies at the heart of any professional kitchen. It can be used to cook anything, since it is no more complicated than a heating system. But the range houses complex technology, just like any other item of prime cooking equipment.

Six months into their apprenticeship, many chefs believe that they have learnt all about cooking ranges and that awesome pieces of prime cooking equipment, such the combi-oven, need long hours of study. Yet while there can be lots of dials and buttons on a combi-oven, all models are built to the same design theory, whereas cooking ranges are not.

A wide choice of ranges is available, from the classic design of island suites to the basic four-burner gas range with oven beneath. They will all do the same prime cooking job, but since they last longer than many other pieces of equipment, making the wrong buying choice will take a long time to correct. The options are as follows:

Open-top four-burner and six-burner ranges

These, the most common type of cooking range, have open gas burners or electric radiants with an oven underneath. Four or six burners or radiants are the most common configuration but, for very busy kitchens, a greater number of burners or radiants is available.

Their main advantage is fuel efficiency. Almost all the heat is directed at the cooking pan, which can be heated very quickly. Having one extremely powerful burner or radiant among the rest - a feature worth looking for when buying a new cooking range - aids the heating up of large pans and allows flash-frying using a wok.

When making a purchasing decision, it is important to study the burner efficiency percentages in order to assess the whole-life cost of the range and the running costs of the equipment. Any supplier should be able to give exact answers to questions about burner efficiency.

So technical is gas burner design that many cooking range manufacturers buy in the gas burner as a separate specialist component, so it is advisable to check for the availability of spare parts.

Solid-top ranges

These consist of a solid cast-iron top heated underneath by either strategically placed gas jets or electric elements. As with an open-burner cooking range, there is an oven underneath. The biggest advantage of solid-tops is that, size for size, they can accommodate more than a six-burner open-top range, due to broader heat distribution across the whole of the top.

Heat levels can also be adjusted in different parts of the top, with rapid boil in the middle and a gentle simmer on the edges. Many are now able to heat just one half of the top, helping energy efficiency.

Solid-tops are usually cast-iron, but carbon steel is now beginning to appear, which means the top can be thinner and can transfer the heat more quickly.

The downside in having the larger cooking area with a solid-top is that it takes longer to heat up and cool down than an open-top burner range and, since the top acts like a horizontal radiator, there is energy inefficiency if just a couple of pans are being used. Also, it is more difficult to fine-tune the heat control on a solid-top, as it is invisible, unlike that on an open burner.

While the solid-top will take a lot of energy to heat up, once it has reached a working temperature the heat-retention capacity of a huge slab of cast iron means the heat source can be turned down and there will still be enough retained heat for low-to-medium cooking temperatures. Some solid-tops have just one centrally positioned burner, radiating the heat out to the edges of the hob. The area directly over the single burner is very hot, but there is gentle heat at the edges.

Boiling tables

Boiling tables have a top exactly the same as a standard cooking range, but there is no oven below. This is useful for reducing purchase cost when there is already sufficient oven capacity but insufficient range capacity in the kitchen. The space below is also a convenient storage area for pans. Boiling tables can be open-top or solid-top, using gas or electricity. Where a kitchen uses a combi-oven by preference, a boiling table could be the only type of range needed.

Island suites

These combine a cooking range with other prime cooking units, forming a joined-up work station around which several chefs can operate at once. Island suites have a reputation for withstanding the most punishing cooking demands in busy kitchens. Many of the prime cooking functions are housed in this single unit, which saves on space and allows chefs to control several cooking functions close to hand.

Island suites come as modular units or in one-piece formats. Modular units are usually bespoke in construction - a type of pick ‘n' mix from a wide range of cooking units, including the cooking range and a choice of fryers, pasta cookers, ovens, griddles, grills, chargrills, induction hobs or any type of prime cooking equipment. The individual cooking units are bonded together on site to form one seamless unit.

One-piece island suites are arguably the most hard-wearing and powerful cooking ranges available. If not built to last a lifetime, it's not unusual for one to have at least a 20-year lifespan. Traditionally used in the grand kitchens of Italy and France, their classic design lines and retro chunky controls offer additional prestige for a chef, similar to the grand style of a Rolls-Royce coupled with the workmanlike qualities of a tractor. One-piece island suites are usually built in the factory and transported to the kitchen ready to be connected up to power.

As well as off-the-shelf configurations, bespoke one-piece suites can be built to order. However, as with a Rolls-Royce, luxury comes at a price, with typical entry-level equipment costing £40,000 and top-of-the-range one-piece island suites priced at double that amount. For this reason, they have tended to be used only in large top-end restaurants and five-star hotels. However, with their ruggedness and longevity outweighing the high initial purchase cost, an increasing number are now being fitted into food service operations, such as universities and large staff restaurants.

Light-, medium- and heavy-duty

What's the difference between these cooking range descriptions?

One of the most vexing aspects of cooking range specification is that different manufacturers apply different meanings to the terms light-, medium- and heavy-duty. Compounding the problem is the fact that, in order to meet a price point for a medium-duty range, a manufacturer can reduce the specification on some of the more expensive parts so that it technically becomes a light-to-medium-duty cooking range. Yet for marketing purposes the range will probably retain its medium-duty rating. Caterers who wonder how an obscure manufacturer can offer a heavy-duty range at a medium-duty price would do well to remember this point.

So how do I know which level I am buying?

Given the lack of an industry standard for these descriptions, buyers should take a close look at the construction of the range, including the thickness of metal and the robustness of castings and controls. Does the door sound tinny when slammed shut or does it close with a solid thud? Door hinges are notorious for breaking under constant use, so their robustness gives a good indication of build quality. Another simple quality test is to feel the weight of the pan supports.

Burner size and output are also indicators of the real duty level of the cooking range. Light-duty ranges will have a burner heat output of not much more than 4kW, medium-duty will have burners around 5.5kW and heavy-duty burners a heat output of 8kW or higher.

In the fiercely competitive world of oven manufacturing, purchase price is also a crude quality indicator. Light-duty ranges should be priced at £1,000 or less, medium-duty at £2,000 or less and heavy-duty at £4,000 upwards.

Energy control

Gas or electric: which is more energy-efficient?

There is no one-word answer to whether gas or electric ranges are more energy-efficient, as there are so many variables. It can even come down to something as simple as using the wrong size of pan on the gas burner or electric radiant so the heat isn't concentrated on the underside of the pan, leading to heat escape and wasted energy cost.