I have a Combi-Oven, what are the effects of moisture to food at 250 celsius and 100% moisture?

[Robert]

In a commercial kitchen, Combi-Ovens are becoming popular; these ovens are a combination of steamer and convection oven combines into one. We are able to reach temperatures of 250 degrees celsuis and 100 % moisture into the cooking chamber at the same instance. My question, what happens to water when it is superheated to this temperature (482 degrees F) and how might the mositure effect the food? I know that at lower temperatures proteins are more moist and cook faster, i.e. chicken cooked at 375 degrees at 30% moisture cooks rapidly and will be very moist. I am trying to determine if a protein is cooked at 480 degrees F will it actually absorb any moisture that might be infused into the cooking chamber or is the temperature so high that it cannot abosorb moisture?

[Andrew M]

Hi there! Excellent questions! Many people who use combi ovens are unsure of what will happen to their food when they place it into a hot oven cavity which is filled with humidity!

First things first. Higher means drier. By this I mean that as the temperature rises, the oven cavity can hold less and less moisture. I know this is not the impression that many combi oven controls give you, but it's due to the physics involved. For example, when your oven is running at 400F, the maximum humidity that you can ACTUALLY achieve is about 17%, regardless of how high your oven parameters are set.

Second. Dry air is thirsty. This means that when you put food into a dry cavity, the dry air will immediately start to drink the moisture from your food. This results in drier food (of course), lower yield, compromised flavor and "mouthfeel", compromised nutritional value, and food that is more difficult to hold hot. Taking into account my first point, it stands to reason that it takes less moisture to saturate the cavity the higher the temperature is. However the key word is "saturated", which means it can not absorb any more. This means that regardless of temp, if you saturate the cavity with steam, your product will stay more moist than if you used dry air only. The only reason to reduce the humidity level from "fully saturated" is to ALLOW some drying of the product, which is crucial for some things like baking a cake, roasting a chicken with crispy skin, etc. Very few products will absorb humidity from the cavity during cooking. Baked goods are one exception.

Third. Humid air (steam) is MUCH more energetic than dry air. Even though the temperatures are the same, who would debate that a regular steamer is "hotter" than a dry oven at 212F? Put your hand over a boiling teakettle and you get the idea of exactly how much energy it takes to heat all that moisture. When it touches you (or food) it releases all that energy. Now imagine that same phenomenon at 350F, 400F, or 482F. Powerful stuff. It is for this reason that we typically don't really need to use temperatures as high as those in a dry oven... we already have more energy at lower temps.

Bonus note: Always be sure that you use proper water filtration on your combi oven. When you superheat steam, the things that people put into steam to make it safe to drink (chlorides etc) can change chemically into things like hydrochloric acid. Not good for your food. Not good for your oven. You will cause corrosion to your equipment and even the pans that you cook on. Combi ovens are not cheap, so be sure to take the extra step to protect your investment with proper water filtration.

Full disclosure: I am one of the Corporate Executive Chefs at Alto-Shaam, inc. We are the leader in North American combi oven sales. The things I outlined in the above paragraphs will apply to all combi ovens, however. You may hear it explained in different ways, but the increased speed and higher moisture content of your food are the two main advantages of combi cooking.

Please feel free to contact us via our Facebook page if you have any more detailed questions regarding combi ovens! http://www.facebook.com/pages/Alto-Shaam/85111386903 Thanks for asking a great question!