If there is any one thing that really makes barbecued meats so delicious and popular, it is the special contribution that smoke plays during the cooking process. Terms such as “slow-smoked meats” or “hickory-smoked ribs” are just two examples of phrases that often make carnivores start salivating in anticipation of eating barbecue.
Cooking meat without smoke simply does not deliver the eating experience of “real” barbecue. Heated debates have ensued over what region has the best barbecue and arguments have been fueled over whether using sauce on barbecue is sacrilegious or required, but when it comes to cooking meats without smoke, most will agree that it is not negotiable. Upon further review, most would also agree that there is nothing simple about smoke – the amazing ingredient produced when wood and fire work their magic.
Nobody really knows when adding smoke to meat really began. It could have started thousands of years ago due to religious practices of offering burnt sacrifices to the gods with the pleasing aromas drifting upwards as part of the atonement of sins. Maybe it started when fires were built in caves and the smoke covered the meat and added flavor.
We know smoke is just the natural by-product of burning wood and regardless of when it started, our ancestors must have determined that smoked meat tasted pretty good. Over time, someone figured out that smoking meats also extended the shelf life of products, which was an important factor in making sure food was available during lean times.
Smoked meats are not confined to barbecue. With any trip down the processed meats aisles of grocery stores shoppers can find cases filled with different smoked hams, bacon, sausages and many other great foods. Even some non-barbecue restaurants have incorporated specialty entrees and even desserts where smoke is a part of the dish and a tempting part of the menu description.
In reviewing many published articles and reading multiple book chapters on the science of smoke, it quickly became apparent that certain people are better suited for specializing in meat science as an area of study versus the academic challenges posed by organic chemistry in college.
Although it sounds simple, smoke is extremely complex. One review article stated that there are over 400 volatiles identified in smoke including various acids, alcohols, carbonyls, esters, furans, lactones, phenols, and other miscellaneous compounds. While phenols probably play the greatest role in smoke aroma and flavor, it is probably like a great symphony and every compound contributes something in its own unique way.
Appearance and wood matters
In addition to aroma, flavor and the preservative nature of smoke, one must not forget its role in product color. Smoked color comes about primarily through the Maillard Reaction and the way that aldehydes and amino acids react when heated to form this important browning reaction that we know from so many foods. Smoke influences how products smell, taste, look and how long they will last.
In the barbecue world, where there’s fire, there’s wood and then smoke. Therefore, understanding a little about wood is important. Smoke comes from the pyrolysis of wood at very high temperatures (600° C). There are three main components to wood: cellulose, which contributes the aldehydes for smoke color; hemicellulose, which contributes furans and other compounds for overall flavor; and lignin, which contribute the phenolic compounds for the smoke flavor.
At the Camp Brisket and Barbecue Summer Camp events hosted each year at Texas A&M University, we have panel discussions focused specifically on wood and smoke. Over the years, we have learned a great deal from pitmasters and other experts on this topic. The investment made by competition teams and barbecue restaurant operators on wood and ensuring a supply of consistent, high-quality wood is high priority. One of the key features emphasized during each panel discussion is the role of seasoned versus green wood. As the name implies, green wood is freshly cut and seasoned wood has been dried over some time, usually measured in months or years. The moisture contents of these two are quite different, and the challenge faced when green wood is used to produce smoke is that the moisture must be eliminated first resulting in lower burning heat. Also, more creosote forms with green wood, which is not a desirable attribute for meat products. Eating barbecue that has been smoked with green wood has been associated with belching and an aftertaste sometimes lingering after the meal.
Hardwoods (deciduous trees) include the fruit and nut woods, which are the preferred woods for smoking, compared to the softwoods (evergreen or coniferous trees). There are a variety of great woods available and widely used, based on their effect when smoking meats.
Hickory – Probably the most commonly used wood for smoking meat. The abundance of hickory through the eastern parts of the United States allows this wood to be available in the areas where much of the traditional barbecue has its roots. One reference stated that hickory gives smoked meats their bacon-like flavor, and yes, most bacon is smoked with hickory. Hickory delivers a great complement to cuts of pork.
Oak – The hallmark of Texas barbecue is oak-smoked meat, especially beef brisket. The type of oak used is principally Post Oak. These trees have been plentiful in the Central Texas area where many of the barbecue founders, as well as the new wave of craft barbecuers make their home. Oak and beef simply go well together with both of them providing complementary bold flavors – not unlike using oak barrels for adding flavor during the aging of wine and whiskey.
Mesquite – An often time maligned wood for smoking meats because of its intensity, mesquite can provide some unique flavors to meats. Mesquite is found throughout the Southwestern United States and is known for burning quite hot. Some restaurants burn mesquite logs into coals and then use the coals to cook. That way, some of the intense flavors are lessened. Mesquite is mostly used for beef.
Pecan – Related to the hickory tree with some of the similar flavor traits. Too much pecan can cause a bitter flavor. Excellent for barbecuing pork and poultry.
Apple – Delicate mild flavor that is fruity and subtly sweet. Apple has gained popularity in recent years, especially for bacon and some other processed meats. It also works well barbecuing pork and poultry.
Peach – Provides light, sweet, and fruity flavors. Peach wood is used for pork and poultry.
Logs, chunks and chips
The pitmaster’s decision about smoke does not end with which type of wood to use. One must also decide what form of wood to use when barbecuing. Commercial barbecue restaurants most often use split logs, and there are a wide variety of “stick burners,” offset or other types of cookers, designed to accommodate these larger pieces of wood. Today, there are a variety of wood chunks and chips that are readily available. Plus, there are different charcoals, lump and briquette, made with the different wood types. There are many forms of wood available for barbecuing, and for grilling, too.
One of the latest barbecue trends is using a pellet smoker. This is a broad category of cookers that use compressed pellets of different wood types to create a particular flavor. These smokers use an auger to meter out sufficient pellets to maintain the desired cooking temperature. Many users of the pellet smokers love the convenience and “set-and-forget” convenience, compared to monitoring and adding logs, chunks, chips and charcoal throughout the cooking process.
There are many options and many venues to obtain wood. Therefore, barbecue enthusiasts, whether backyard or commercial, can experiment with types or forms of wood to create unique flavors of barbecue. As barbecue season arrives, dust off those cookers and try a new type or form of wood. One advantage to experimenting with smoke from different woods is eating the results.