The phenomenon you're referring to is commonly known as the "stall" or "barbecue stall" in meat smoking. During this phase, the internal temperature of the pork (or other meats) can plateau or even decrease for a significant period of time before continuing to rise. The stall is primarily caused by evaporative cooling and collagen breakdown. Here's a breakdown of the reasons behind the stall:
Evaporative Cooling: As the meat is exposed to heat during smoking, moisture on the surface evaporates. Evaporation is a cooling process that absorbs heat energy, which can offset or slow down the rise in internal temperature. This cooling effect can be quite significant and can lead to an extended stall period.
Collagen Breakdown: Pork and many other meats contain connective tissues, primarily collagen. During the stall, the collagen undergoes a process called collagen denaturation, which involves breaking down the collagen fibers into gelatin. This process requires energy and heat, which can cause a temporary plateau in the internal temperature as the collagen is being converted.
Heat Transfer: During the stall, the heat energy from the smoker is mainly absorbed by the moisture on the meat's surface and the collagen within the meat. As the collagen slowly breaks down, the absorbed heat energy is utilized for collagen denaturation rather than increasing the internal temperature.
Plateau Duration: The duration of the stall can vary depending on various factors, including the meat's size, thickness, fat content, and moisture content. Larger cuts of meat or those with more connective tissue tend to experience longer stalls. The evaporative cooling and collagen breakdown processes continue until the moisture evaporates and the collagen is fully converted into gelatin.
To overcome the stall and resume the temperature rise, there are a few techniques you can try:
Wrap the Meat: Wrapping the pork in foil or butcher paper can help retain moisture and reduce evaporative cooling, allowing the internal temperature to rise more steadily.
Increase Heat: You can slightly increase the heat in your smoker to help counteract the evaporative cooling effect and promote a more consistent temperature rise.
Patience: The stall is a natural part of the smoking process, and patience is often required. Eventually, the internal temperature will start to rise again as the evaporative cooling decreases, and collagen breakdown completes.
By understanding the factors contributing to the stall and employing appropriate techniques, you can manage the smoking process more effectively and achieve the desired outcome for your pork.