How is fat freezing performed and does it burn the skin?

Thank you for your question. Fat freezing should not burn your skin. The device used for fat freezing cools the skin to a level which causes fat cells to freeze, but does not harm any surrounding tissue. These frozen fat cells disintegrate and then safely leave the body through natural processes. The most common side effects are soreness and bruising. Burning, should not occur. 

CoolSculpting by Zeltiq is calibrated to deliver a temperature that is low enough to send fat cells into a slow death cycle, but not low enough to affect or “freeze” skin, organs, or other tissues. In fact, referring to CoolSculpting as a “fat freezing” method is erroneous. That fat isn’t “frozen”; it’s cooled to the point where the fat cells can no longer function. Once the fat cells are sent into this slow-death cycle, they begin to destruct. Their components are then swept away and filtered through the lymphatic system. The exact temperature is a company secret.
While you may feel a cooling or numbing sensation on your skin, it will neither be “burned” nor “frozen” during your CoolSculpting session. However, your question underlines the importance of choosing to work with a board-certified dermatologist who has been certified by Zeltiq as a CoolSculpting practitioner. “Bargain” fat-freezing methods could result in injury, as they may not deliver the right temperature to the fat. Be sure you only work with a board-certified dermatologist to get your fat removed and your body sculpted. 

HI angdouglas.  The temperature at which skin freezes is colder than the temperature that Coolsculpting from Zeltiq/Allergan uses (programmed into the machine) to freeze fat, so no chance of a "burn".  In addition to temperature, the length of time that the fat is cooled is also relevant to getting a good result.  Talk to your Coolsculpting provider about which applicators they suggest because the older ones use suction (more discomfort) and take longer treatment times; the new ones use a colder temperature without suction and shorter treatment time.  Best wishes,