THE FIELD OF COMBAT
While our title may suggest we’re about to engage in a battle of appliances, we’re not aiming for a fight to the finish – any ‘winners’ or ‘losers’ will depend on your priorities, circumstances, and choices – and individual judgments may vary. Our role is more ‘expert witness’ than ‘umpire’ – we’re only here to outline the lay of the land.
For those who simply want a bullet point bonanza filled with pros, cons, and fun facts, scroll to the bottom of this article – for everyone else, stick around for a ride on the rollercoaster of history, relevance, the pursuit of excellence, and the consequence of industrial, professional, and other cultural influence and mediation.
INTRODUCING THE PLAYERS
1. The Microwave Oven
Since its entry into the UK domestic market in 1974, the microwave oven has become a feature of most UK kitchens. By 1994 67% of UK homes were known to house a microwave, and since 2005 the stats show an excess of 90% saturation, with incremental rises year on year. There is a consequent, and often unquestioned, assumption that most kitchens require one, whether in the form of a built-in appliance, a countertop model, or an in-the-closet secret.
2. The Steam Oven
Much newer to the market – arriving around the late 1990’s – steam ovens hold a minority position in relation to the microwave in levels of recognition and adoption, and are still often ‘misunderestimated’ by, or yet to be introduced to, a majority of people.
FIRST OUTINGS
Both of our protagonists made their culinary debuts in professional spaces – adopted by those who believed in their promise and were willing to invest in both the heft of their early-stage physical presence, and the price of their early adoption. Adaptation for a domestic market has followed proven track records in these heavy-duty kitchens, and the further development that has enabled them to shrink to fit – size-wise and price-wise – into domestic space.
THE STARTING BELL
Our conversations with customers often begin with an expectation on their part that a microwave is a non-negotiable for heating and/or defrosting things in a hurry – ready meals, leftovers, baby milk, etc – no shame or shade there (although for anyone who thinks it’s acceptable to use a microwave to reheat a cold mug of tea, please see us after class!).
Many assume that they have no use for a steam oven because a) they haven’t used one to date, and b) they will be expensive. Most people also expect their microwave to be separate from their primary oven.
So we’ll maybe start by pointing out that re-heating and defrosting can also be performed in a steam oven (along with a whole lot more besides), that it’s possible for an oven that enables steam to function as the only oven in your kitchen – like a friend you already know, but with additional benefits – and that price differentials between microwave and steam-enabled ovens are often marginal when comparing the kind of ‘built-in’ models that we are normally in the business of specifying.
HISTORY & SCIENCE
Microwaves
The ability of microwaves to heat up food was an accidental discovery, made at the end of the second world war by an engineer with a melting chocolate bar in his pocket (a potentially semi-apocryphal story for another time). The working effect of the microwave is not overly complex: microwaves make molecules vibrate – notably water molecules – thus creating energy that in turn generates heat. If you subject something – anything – that contains water molecules to microwaves, it will start to ‘cook’ – ‘Simples’!
Inside an oven cavity, micro–waves pass through, are absorbed by, or bounce off surfaces exposed to them, according to the material composition of those surfaces. For example: a potato will absorb the waves (turning it into a ‘hot potato’), the glass dish you heat it in will let the microwaves pass through it, remaining unaffected by them, and the metal oven walls will ‘bounce’ them, deflecting them back towards the potato. Add a turntable – to give a best chance of evenly distributed wave penetration where it’s most wanted – and the random distribution of microwaves inside a well-sealed oven will ‘cook’ food placed inside it in reasonably predictable fashion.
Steam
Steam has been used as cooking method for as long as humankind has cooked, for very good reason – because steam carries heat efficiently, evenly, and without drying things out. Ovens that create only steam predate combination-steam versions (ie where steam and dry heat can both be used, either separately or in combination with each other). The addition of hot dry air adds the colour and the crispness that is associated with additional flavour and enhanced texture – it’s the chemistry of how food ‘browns’ and becomes increasingly appetising while cooking. This latter effect (scientifically referred to as ‘The ‘Maillard Reaction’) is something humankind has also long known to be delicious even if we couldn’t previously name it.
Who might claim credit for introducing steam-assisted ovens is sometimes disputed and not easily verifiable, but what we do know is that that their origins are linked with those who require or desire exceptional levels of control, precision, and predictability as part of their daily cooking practice (ie chefs).
At entry level for a domestic market, there are now convection (fan) ovens capable of adding simple ‘bursts’ of steam (by injecting water into the cavity for the heat inside the oven to turn into steam), and we can work through the levels from there to the opposite extreme where we find those that can generate steam heat through a boiler that sits outside of the oven cavity before introducing it inside the oven with absolute precision (for both temperature and humidity). The former goes some way to improving oven performance, while the latter introduces incredible levels of accuracy and nuance in how food gets cooked that help to preserve or improve: texture, flavour, nutritional value, cooking time etc.
DOMINANCE OF THE MICROWAVE
Cultural
Microwave ovens have gained an important foothold through their shaping of our food systems, our behaviour, and even, on occasion, our cultural conversation. When Nigella referenced her ‘mee-crow-wah-vay’ on TV in 2020, social media lost its collective mind! What started with Nigella maybe gently mocking her own reverence for this often unsung, relatively low status, and (maybe importantly) socially levelling appliance, gained viral momentum – uniting nations of commentators in their mock outrage and comedic confusion – and earned it a BAFTA nomination as a ‘Must See Moment’.
Behavioural & Persuasive
You only have to type the word ‘microwave’ into the average supermarket on-line shopping app to find swathes of microwaveable, convenience foodstuffs – marked as such as a result of the pre-processing of the food inside them and/or the packaging that contains them: the microwave presented as solution to a problem of ‘time’, ‘skill’, or ‘volition’ when it comes to preparing food.
Product developers, manufacturers, and marketing departments have been deployed to great effect in getting us hooked on the microwave by means of what we do with it rather than by highlighting its features – for, plus or minus a few watts of energy there’s not much to choose functionally between most brands and types of microwave oven.
There’s good reason we may see more ads for microwave popcorn than we will for the appliance itself.
INTERNET INCIDENTALS
To research the practice and the science of the microwave oven is also to find an internet littered with tales of: exploding eggs (inside and outside the oven), with consequent injuries and lawsuits; steaks rendered both partially thawed and partially cooked in ‘worst-of-both-worlds’ scenarios; careless, difficult-to-love, co-workers splattering their lidless, gloopy, sauce re-heats around the insides of office-based machines – alongside handy hints and tips for ‘best ways to clean’ (ironically, by generating steam inside them), and descriptions of the focus groups and developmental science used in the service of clarifying packaging (literally), so that a bowl of long-life Campbell’s soup is rendered visible, and capable of taking 15 fewer seconds to heat than had previously been possible – what profit is to be gained, and by who, from those additional 15 seconds is perhaps something for each of us to sit and contemplate.
INNOVATIONS
Microwaves in the USA
Across the Pond, where convenience food culture first imagined the hot mess of a ‘TV dinner’ (an idea that found easy, early synergy with the microwave) they have been fond of siting microwaves ‘conveniently’ above a range cooker – proudly around or just above the eye-level of many, a ‘fugly’ and unmissable focal point for the kitchen, and an appliance you may need to raise your arms above your head to use.
Realising – eventually – that this might not be for everyone, the latest idea that is exciting the US luxury market involves an under-countertop drawer which, bizarrely, manages to be much less ‘out of sight’ than it sounds.
Further innovation inside this drawer follows the removal of the turntable – until now so essential to evening out wave distribution, but also now incompatible with the necessity of siting the microwave generator in the roof of the machine. In its stead something called ‘inverter flatbed technology’ has been added and, while the drawer is not currently available in a UK market, the inverter tech is filtering through.
What is Inverter Technology?
Traditional microwaves adjust power levels by administering harsh zaps of high power in varying time-lapsed, intermittent bursts – a means of allowing generated heat extra time to move inward from the edges towards the centre. Inverter tech reduces the power level, and keeps it at a constant flow (no on and off audible buzz for this machine) – this takes food longer to heat but is subtler in its effect and better for food that is particularly sensitive to high heat (eg chocolate), or otherwise with high fat or high sugar content – fat and sugar molecules not vibe-ing quite as flexibly with high-power microwaves as those of water.
Steam in the U-of-K
Maybe our difference with the US lies in our different habits and ideas on where we look for ‘progress’, or maybe – with microwave technology already appearing to have found its limits in the cooking space – we just prefer our innovation in finding tech that renders the microwave outclassed. Whichever way you look at it, the steam oven is making greater early impact in the UK and the rest of Europe than it is in the US.
Brands are still testing out their messaging for steam – often including ‘health’ in a steamed vegetable, ‘convenience’ in a trayful of fluffily steamed rice or gently, and safely, ‘boiled’ eggs (with degrees of perfection hitherto unknown), the ‘sous-vide’ capabilities of a chef in a high-end (or high-turnover) restaurant, and the ability to ‘regenerate’ food – which is where we find ourselves back exactly where we started, in a discussion of heating ready-prepared food, where the steam oven will outperform the microwave on result, but may lose points on time.
‘SHALL I COMPARE THEE …?‘
Direct comparison may be futile when the two different appliances have different advantages and ambitions. One is aimed – at its pinnacle – towards achieving the best that scientific discovery and human creativity can offer, the other has developed around shortcuts and time and energy-savings. Each has different supporting structures – and each perhaps plays to its own strengths, even as they overlap.
And in the current era – post pandemic and during an energy crisis – when celebrity chefs and food writers have seemingly been called to remember, embrace and celebrate previously unappreciated microwaves – by using them to cook with not just to re-heat – some of them, perhaps not co-incidentally, also making some dough on the side out of associated book deals and new ranges of cookware – it might be worth noting that some of the best results that they are achieving is where they have done what is necessary to help the microwave generate steam.
CLOSING STATEMENTS
By way of closing statement, and in the interests of full disclosure, the personal choices of the writer of this article and the founders of Day True, is that none of us currently owns a microwave – although, that billboard popcorn ad, with its clever connections and ASMR soundscape, did – for a brief moment – press a personal button, marked ‘wistful desire’!
Read on for some ‘quick and dirty’ pros and cons, and a few fun facts:
PROS & CONS
Microwave
Pros:
- Microwave ovens are a fast and easy method of heating and/or de-frosting food with reasonably predictable results.
- Supermarket ready meals and other industrially manufactured snack foods are often created with the microwave in mind: presented in microwaveable packaging, with easy-to-follow instructions included.
- Microwave ovens are low on energy use because they are only normally used for short periods of time – they are not otherwise inherently energy efficient.
- Microwaves heat the food directly, not the air around it – they heat through direct penetration of the food – the penetration is relatively shallow, and food heats from the edges inward. As a result, food heats up faster in a microwave than food heated in ovens that heat the air around the food first.
- OTOH, for the same reason, food cooked in a microwave will also cool down faster than food cooked in an oven.
- Microwave ovens don’t require de-scaling, although they do require regular internal cleaning – particularly when lids or other coverings are not used.
- Cleaning a microwave after each use is, however, generally just a quick wipe down.
- Combi-microwave ovens can be used to speed up cooking time by combining regular heat with microwave speed.
Cons:
- Only certain materials are safe for microwave use – beware of metals and plastics if not marked as safe for microwaves.
- Microwave cooking can cause splattering inside the oven – because water molecules vibrate more readily than other ingredients and will create pockets of steam that need to escape.
- Microwave ovens used to cook uncovered ingredients will need frequent cleaning to ensure that their surfaces are neither contaminated nor disgusting and that food splattered inside does not get ‘cooked’ onto the oven surfaces.
- Microwaves rarely improve the texture of food.
- All microwaves cook unevenly, leading to cold and hot spots in food – results are dependent on a variety of factors, not least of which is the ‘density’ of the food being microwaved and how evenly that density is distributed
- Uneven cooking is why most microwave ovens contain a turntable and why you often need to pause and stir food frequently (frequent stirring also helps prevent splattering).
- Traditional microwave ovens control power by turning full power on and off intermittently. Taking more time at lower power settings tends to give better/more even results – less overcooking at edges, less splattering
- Foods with a membrane (eg: eggs, potatoes, etc) can explode inside or outside the microwave – because steam generated inside the membrane creates a build up of pressure that eventually requires a release.
Fun Facts:
- Microwaves are so called because of their short length. They are generated by a magnetron (involving magnets and a vacuum tube).
- Ice cubes have trouble melting in a microwave – because the water molecules in the ice are tightly bonded and so can’t vibrate as readily as non-frozen water molecules. It’s one of the reasons that contributes to food defrosting unevenly.
- However, if putting an ice cube onto, eg cooked rice while microwaving it to re-heat the rice, heat generated by the rice will slowly melt the ice, the melted water will start to generate steam, and the rice will cook in the steam and re-heat better than it will by microwave alone.
- Grapes, or anything grape like in size and composition (gooseberries, blackberries, quail eggs, …) are inclined to create a fireball at points where the skin of two of them touch while subjected to microwaves – this is due to the creation of plasma (the same thing that creates lightning and is found in the sun). For some reason, demonstrating this has been considered a fun party-trick – if also one that risks damaging the inside of the microwave.
- The dedicated popcorn button in most microwaves is contraindicated by all those who know anything about popping popcorn – it’s a button with a timer, and cannot tell if/when popcorn is overcooking/burning.
- The tech and innovation contained in a microwave popcorn bag, while massively sophisticated, is still not able to solve the problem of how to get all the kernels to pop.
- while a microwave makes good popcorn, it cannot reheat bread successfully.
- Microwave cooking took on a new gloss during the pandemic (when people got bored of having to cook three meals a day). This new tendency toward microwave use became more exaggerated when the pandemic was followed by an energy crisis, and as it became relatively more expensive to turn on a conventional oven.
- The new evangelicals for microwave cooking tend also to have skin in the game of selling products that support microwave cooking – we may find it hard to tell the chicken from the egg of this, but for those shilling product, rest assured, we see you!
- if you turn the microwave oven on with nothing in it you may end the life of your oven – microwaves need to be absorbed by ‘something’ – they can be self destructive when bouncing into themselves.
Combi-Steam
Pros:
- Steam carries heat well and carries it evenly – it’s a tried and true cooking medium that has been used for centuries.
- Dry air helps things to brown and introduces new flavour compounds via a ‘Maillard’ reaction that makes things taste good and gives them an appealing colour.
- With a combination of steam and dry heat, you can heat food up and cook it with a high degree of control, and make it look, feel, and taste better than food that has been microwaved or cooked in a conventional (hot air only) oven.
- Combi-steam ovens will improve the texture of most roast meat and will reduce cooking time from a conventional oven (because the steam is a more efficient conductor of heat than dry air)
- Combi-Steam ovens come in compact (45cm high) and regular size (60cm high) options. You could substitute a full size combi-steam oven for a regular oven, and use it for many of the same things as a microwave.
- Steaming in an oven is an efficient substitute for steaming on a stove top, especially if you are cooking anything at scale (eg rice, eggs, vegetables …) and value predictability in your results.
- Vegetables retain more colour, nutrients and flavour when steamed than they do when they are boiled.
- many foodstuffs can be cooked with a degree of absolute/scientific precision in a Combi-steam oven – especially when sous-vide techniques are applied (ie cooking at lower temperatures in controlled conditions, to create exact results). Sous vide techniques don’t always require that foodstuffs are cooked in vacuum sealed packaging or circumstances.
- a steam oven can be used to make delicate items where heat is necessarily precise (eg egg custard – the base for an ice-cream), lemon curd etc. It can even melt chocolate, so long as the chocolate is kept away from direct contact with the steam.
- using precision techniques need not interfere with the creativity of the cook – combinations of ingredients, new ideas, and finishing touches are still important features, but certain forms of cooking are always based in scientific fact. The oven is simply a tool that can help you build an understanding of how to cook things successfully.
Cons:
- There is a learning curve to using a steam oven if you have never used one before – not all elements are intuitive, and guides are useful at early stages.
- The steam oven will need ‘cleaning’ (/drying) after each use.
- unlike for a conventional oven, pyrolytic cleaning is not normally an option.
- Depending on the hardness of the water used, steam ovens will require regular de-scaling (every few months might prove an average, but much depends on how often they are used and how hard the water settings).
- Reheating is not as fast as in a microwave – although you can re-heat a plate of food in about 12 minutes in a Combi-steam oven.
- The oven can be used to re-heat food on the plate on which you will serve it, but the plate will also be heated in the process and will not be able to be handled without a heat-proof cloth or glove.
- steam ovens without ‘supression’ and/or end of programme features enabled, may open with a face full of steam – glasses wearers beware!
- A steam oven typically uses more energy than a microwave, because of the time it takes to heat up and then heat or cook food.
- Sadly, a steam oven cannot pop corn, although it will be able to re-fresh bread that has started to dry out and stale (NB: not bread that has started to mould!), and a Combi-steam oven can also toast it. You can still pop corn on a stove top, although, admittedly, not to our knowledge in specially made packaging.
For our help, visit our ‘Contact’ page – our showroom kitchen has working examples of the appliances we like best, and we have lots more to show and tell when helping you design your new kitchen.
