A Southlake Inventor Builds a Better Barbecue Smoker

I recently spent some time with a $650, six-volume, 60-pound text book called Modernist Cuisine. You may have heard of it. What you may not have heard of is the Karubecue. If you’re a ‘cue nut, you need to. Here’s why.

( from my story in the the June issue of 360 West Magazine, digital version here)

At 2,400 pages, Modernist Cuisine: The Art and Science of Cooking isn’t everybody’s idea of a leisurely read. But for the food-obsessed—and I count myself among them–the six-volume, $650 cookbook by former Microsoft executive Nathan Myhrvold is a trove of treasures. Myhrvold and his team of chefs and laboratory shamans have broken down nearly every aspect of cookery into its scientific parts, studying then explaining (and demystifying) why things work or don’t work in the kitchen. When Myhrold says a charcoal grill produces more radiant heat than a gas grill—then throws down the equation to prove it—who can argue? How do you cook a pot of dried beans so they always come out tender? Myhrvold says to cook them in bottled water. So when he tackles the lore of smoking meats, deep in Volume 3, I’m wide awake for the sermon. Myhrvold says there’s more to producing great barbecue than just keeping the temperature of your pit below 250 degrees for a long time.

“The role of fire in smoking is to burn at approximately 750F and produce gases from pyrolysis that flavor the meat,” he writes. “Higher and lower temperatures can be used but do not produce the same taste.” The smoke produced at lower temperatures, near the 225F sweet spot of the low-and-slow school of ‘cue, tends to be loaded with heavy molecules that impart a bitter, acrid taste to meats. At high temperatures, the smoke is light and sweet, and those big molecules have been burned off. But how to do you get the very hot smoke to the party without also bringing the heat? Myhrvold offers a solution called Karubecue smoker. I didn’t have to look far for its inventor, Bill Karau. He lives in Southlake. And, like Myhrvold and me, he’s a barbecue nut.

Bill Karua (foto Ralph Lauer)

The Karubecue (foto Ralph Lauer)

“It’s almost impossible for a home cook to make great barbecue with an offset smoker — the one with the firebox on one end and the cooking chamber on the other,” says Karau, an engineer who has extensively studied the science of smoke and fire in an effort to produce better ‘cue. Karau’s patented Karubecue is a nearly foolproof smoker that can turn a novice pitmaster into an expert. It’s a project he’s worked on since 2004, when he realized, after sampling a lot of commercial barbecue, that there has to be a better way.
“The problem with the typical offset smoker is that you have to build a hot enough fire to produce good quality smoke, but that usually generates way too much heat. Most cooks throttle down the heat by closing off the intake vents. That reduces the fire by restricting the oxygen flow, but that’s the opposite of what you should be doing.
“You need a very hot fire to produce good-quality smoke,” explains Karau, echoing Myhrvold’s text. “If you open your grill and see dark, billowing smoke, then that’s bad-quality smoke. It’s full of heavy molecules that carry bitter flavors and leave a black crust on the meat.” What you want, says Karau, is the barely visible, blue-tinted smoke that results from a very hot fire.
How, then, does the Karubecue generate good, sweet smoke without also bringing the heat? Karau tweaked a traditional offset smoker, using a fan to draw the smoke from an external firebox back through the hot coals of the fire, then into the sealed smoking chamber. By sucking the smoke back through the hot coals, he burns off all the bitter-tasting smoke molecules, leaving just the light, sweet notes for cooking. He regulates the heat of the cook box by programming a thermostat to control how much of the hot smoke he channels into the box. The principle is essentially the same as smoking a pipe, where hot smoke is drawn down through the hot pipe bowl.
Admittedly, Karau is a thinking man’s cook. His website includes a detailed breakdown and a treatise on the smoke ring.
But the proof is in the meat: The chicken and ribs were not stained with the dark bark of an oxygen-starved smoke. Instead, they were beautifully browned, moist and tender. The ribs, too, were just about perfect, a rich mahagony color but not a trace of sooty taste.

Check out Ralph Lauer’s pictures here, under Obsessions.

Bill Karau builds each of the smokers, called the B-30, in his Southlake garage, one at a time. He also has custom-built a larger unit, the X-400, to test his methods on a large scale for possible commercial use. A custom Karubecue will cost you about $1,300. Karau at some point hopes to outsource the fabrication — and get back his garage — which will lower the cost to below $900. www.karubecue.com