Continuing my awesome ability to find super deals on the Internet, I stumbled across a posting on Craigslist for an unused Gaggenau combi oven for under a grand. That’s a chunk of change no matter how you slice it, but considering these things go for $3000, it was quite a find. There had to be something wrong with it. I went to take a look and heard the story: the guy bought the oven at an auction from an appliance store that went out of business, collecting a wide variety of gadgetry for he and his girlfriend’s dream kitchen. Then, she left him, and headed back to China. He was trying to get rid of all of it. No scratches and everything seemed to look good – so I went for it. A few days later with the help of my neighbor, and I had it installed and, thankfully, working up above my fridge.
Now I have a convection and steam oven to control the dry bulb and wet bulb temperatures separately. This is something Nathan Myhrvold calls “the most important concept in cooking that you never heard of.” Dry bulb temperature is measured by a temperature sensor placed inside the oven. Wet bulb temperature is measured by a temperature sensor wrapped in a wet cloth. The relative humidity can be measured by the two temperatures: the higher the wet bulb temperature in relation to the dry bulb, the higher the relative humidity.
Why is this important? Because food, being comprised of mostly water, feels only wet bulb temperatures. Dr. Myhrvold gave this example in an interview to Food Arts magazine:
In Chicago in the winter, your oven is baking about 20 degrees lower than it would at the same temperature setting in New orleans in the summer. Also, how full is your oven? the variations all have to do with wet bulb temperatures. With a combi oven or a Cvap, we control this phenomenon.
If you’re in an area of low humidity, such as a high-elevation area, being able to control the evaporation rate through the use of dry and wet bulb temperatures allows you greater precision in your cooking. Which results in a better meal. And who doesn’t want that?
So, what should be the first thing I should cook in my new combi oven? Something from the Modernist Cuisine cookbook, naturally.
Steaming A Steak
In the book in the section on combi ovens, they give a few example recipes. I settled on the rib eye steak. It requires convection, steaming, different temperatures, and use of both the temperature probe and timer. A nice workout for the Gaggenau to see if it’s up to snuff. I went up to my local butcher shop to grab a steak. In Seattle, we have the pleasure of having lots of butcher shops to choose from. Many are new and have the farms the meat is from listed next to the cuts, and have a contemporary layout, with a self-conscious feel. I go to Bob’s Quality Meats, which is an old school place. No fancy display, just good cuts of meat and home made sausages. He’ll tell you where it’s from if you ask, but he’s not trying to prove a point, probably because he never thought buying from local farmers was some big epiphany in the first place.
With my steak in hand, I followed the recipe. I preheated the oven to 130F at 100% humidity, then placed the steak inside the oven and inserted the thermometer. From there it cooked until the internal temperature was 130F, for about an hour.
The steak then went through a 25 minute drying process, where the temperature is slowly increased, but the humidity is set to zero, so the moisture slowly evaporates from the surface of the steak so it can be seared. That way the wet bulb temperature does not exceed the internal temperature of the steak. It reminded me of what my fingertips look like when I’m in the water for too long. Not the most appetizing thing. I wondered if this was going to work.
After the drying process, you pull out the steak and heat up the oven to 575F to sear it. The Gaggenau, however, only goes to 450F. They give an option in the cookbook to sear it with a torch, but I decided I wanted to see if the oven could get to its highest temperature so I set it to the max. The remaining steam in the oven quickly evaporated. The pan to catch the drippings began to warp. The temperature readout displayed 465F. Whoa. Better sear that thing. I put the steak back in and seared it for 2 minutes on each side, using the timer.
Everything worked perfectly.
From what I could tell, I was basically doing sous vide using steam instead of a water bath. The other difference was the fat dripped away from the meat, where it would stay in the vacuum sealed pouch if it was done sous vide. Was it better than sous vide? Better than throwing it on the grill? Can’t say as I didn’t do a side by side (by side) comparison, but it was a great steak. And more importantly, the oven I bought off Craigslist was working just fine. A success all around.
Hi there. Great post! I have the same combi oven as you and i’m wanting to actually cook Sous Vide with it. Have you tried this at all? I’m thinking of putting the vacuumed bag directly in the perforated tray and then continuing as you have here. Thanks
Yes I have. My immersion circulator once broke down and I saved the food by throwing it in the combi oven. Give it a shot and let me know how it turns out!
Hi there. Ok I tried the Sous Vide method in the Gaggenau. I did some lamb burgers at 60 degrees, however I notice that the display registered 62 for most of the cooking time. I will continue experimenting, maybe the way to do it would be to use a vessel filled with water in the Gaggenau oven. Thanks again.