Smoke ring (cooking)

A smoke ring is often considered the hallmark of great barbeque. Many notable pitmasters and barbecue restaurants achieve this desirable trait with ease, and it is the goal for many backyard chefs as well. The smoke ring is a region of pink colored meat in the outermost 8-10 millimeters of smoked meats. It can most commonly be observed in smoked chicken, pork, and beef. More specifically, it is the defining factor in whether or not smoke (pork) ribs, or (beef) briskets are cooked well. There is some debate as to whether or not the presence of the smoke ring is actually an indicator of quality of the finished barbecue product, however, it is widely considered to be a desirable characteristic that foreshadows tenderness and juiciness.

The pinkish color in meat is typically due to the presence of a compound called myoglobin. Myoglobin typically darkens and turns brown when heated above a certain temperature. This is why the perimeter of a cooked steak is darker in color than the red inside; as the lower temperature of the middle of the steak was not sufficient to cause the myoglobin to lose its pigment.

When smoking meat, a different process occurs than in other cooking methods. Organic fuels such as wood and charcoal, when burned, produce nitrogen dioxide (NO2) gas. When this gas dissolved into the meat, it reacts with the hydrogen molecules and becomes nitric oxide (NO). The NO combined with the myoglobin form a stable pink molecule that does not denature in the heat. The depth of the smoke ring is determined by how far the smoke can permeate into the meat.

There are several considerations when smoking meat that will determine the extent at which a smoke ring will form. However, the most important factor is the fuel source and that source's production of NO2. The highest concentrations of atmospheric NO2 can be achieved in a smoker through the utilization of charcoal briquets, or wood fires; both of which are capable of producing up to 200ppm (parts per million) NO2 in the cooking chamber. It has been suggested that greener woods produce more NO2, but are less suitable for cooking.

Cooking "low and slow" is said to be key in the development of a smoke ring. This methodology, often cooking at temperatures under 225 degrees F for long periods of time, allows smoke to penetrate the meat and react with the myoglobin before the temperature causes a reaction with it causing it to darken. For this reason, keeping the exterior of the meat moist via basting or spritzing is often recommended.

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Wikipedia