/ The secret of tasty breast and ribs lies in food chemistry and phase transitions. TagFos / Getty Images Share this story
Imagine this nightmare scenario of the Labor Day. You have invited a large group of friends for pulled BBQ pork or a delicious beef breastpiece. That morning you confidently put your meat in the smoker, a handy digital thermometer in place so that you know when the internal temperature reaches the perfect point. Everything seems fine for the first two hours, but suddenly the temperature stops. And it remains constant for hours and hours, while your friends become hungry and hungry and you are forced to order pizza in desperation.
You have just come across the curse of aspiring pit masters: the Stall (also known as the Zone or Plateau), a common phenomenon when cooking at low temperatures. What exactly makes the stall a multi-year topic of debate among BBQ enthusiasts. Is it a protein called collagen in the meat that mixes with water to convert it to gelatin at 160 ° F? Or is it due to fat burning, causing lipids to change into fluid?
A few years ago a professor at the Boston College did the experiments and came up with a definitive answer: evaporative cooling. The meat sweats during cooking, so that the moisture comes in, and that moisture evaporates and the meat cools, effectively removing the heat from the BBQ. Nowadays, Blonder is the resident science advisor and myth breaker on the popular BBQ and grill site "I spend a lot of time organizing bar fights, actually," he joked.
A slow-cooked passion for cue
Blonder has always been an enthusiastic, inventive cook, when the only tools he worked with were a single hob and a large pot. When a friend came from Hawaii, they baked a whole pig on hot rocks in the backyard. Once the scientist, Blonder put a couple of thermocouples in the carcass to monitor the changing temperature during cooking. So when he heard about the stable, he decided that too.
First he mapped the actual state. For his experiments he used breast and pork tenderloin, because this is the most popular meat for slow roasting and smoking. He used a thermostatically controlled smoker for cooking and maintained a careful 150 ° F. As expected, the booth went on after the first two to three hours, and it took about six hours for the internal temperature to rise again. It is a useful example of a simple phase transition, with an initial rise and then a long leveling, before it rises again to rise to the critical tipping point.
The backyard experiments of Greg Blonder produced this chart that clearly stole the & # 39; showed. Greg Blonder
Blonder discovered that collagen is probably not the culprit, because it accounts for only about a quarter of the total protein in, for example, a pig shoulder (18 percent, with 65 percent water and 15 percent fat). The basic hypothesis is that the collagen absorbs as much energy as it chemically converts into gelatin, there is not enough more to let the meat rise in temperature and you get the barn. Certainly, the collagen begins to melt at about the same point as where the box starts, but according to Blonder's calculations that is just a coincidence. There is simply not enough collagen in the meat. He proved it by wrapping a six-pound pork steak in aluminum foil before boiling and only using a friction on the other six-pound butt. There was no stall in the pig-wrapped end of the pig, and it should have been there if collagen was the cause.
As far as the melting fat hypothesis is concerned, Blonder also tested it. He placed a piece of pure beef fat in a smoker together with a sponge dipped in water, put thermocouples in both and boiled at 225 ° F. Again, there was no stall with the beef fat. But the sponge showed a clear stable after the first hour and the temperature did not begin to rise until all the moisture had evaporated. Voila! The culprit is evaporative cooling.
That is why nowadays a growing number of competitive pit masters wrap their meat in aluminum foil after the first few hours (usually when the internal temperature is 170 ° F), along with a splash of apple juice, beer or even Mountain Dew. Blonder does not do that, because the consideration is that you have the crunchy, tasty & # 39; bark & # 39; on the meat surface does not get – a product of evaporative cooling that removes so much moisture from the surface – and he likes the added crunch and "Taste bomb" when he cuts it into pieces with the rest of the meat before serving. But he recommends the aluminum foil if you are not an experienced pitmaster, especially if you use a large offset grill with a lot of airflow (compared to an egg or Kamado). The truffle of the tinfoil can shorten the cooking time by half if you cook on the standard 225 ° F. "It is absolutely infallible," he said. Increasing the cooking temperature to 250 ° F can shave for another hour or two. Or you can just do it the old-fashioned way and keep it going for the full 14 hours.
A lump of beef fat does not show a stall; a soaked sponge. Greg Blonder If 14-15 hours just seems to be too much of a day-long commitment for your Holidays, Blonder suggests trying something he calls pork-us interruptus: start the process the day before and when the pork tenderloin or breast hits the stall, take it from the smoker, wrap it in foil, put the foil wrapped meat in a plastic bag and immerse it in ice water to cool. Then store the meat in the refrigerator overnight and finish cooking the next day. He insists that you can even finish it in your oven, because you already have the smoky taste in the meat. "It takes the stress off the chef," Blonder said. "Because the worst thing you can do is panic when you hit the barn and your guests show up and you do not have meat."
Another useful (scientific) tip: you have to pre-bake your meat a couple of days in advance, because it takes so long before the salt in the meat is diffused. Salt is essential for the cooking process, because it adds flavor and reduces moisture loss, preventing excessive shrinkage. But be warned that some parts of meat are pre-injected with phosphates, and if you add salt, it will be too much. That is also the reason why Blonder does not add salt to the mix of herbs he uses in his go-to rubs. (He says you can add the fudge or marinade a few hours before cooking, it will not penetrate deep regardless.)
Blonder is adamant that these are colored by their personal preferences, and that there is enough room for adjustment if your taste is different. "I'm never going to tell you that there is only one way to do it," he said. "But if you want to achieve a certain goal, there are better ways to achieve that goal through science."