ThermoBlog by Martin Earl
How to Grill Shrimp: 120°F Temperature and Thermal Principles
Grilled shrimp is one of the delights of summer. They dress well in fresh, light flavors and don’t weigh you down quite as much as, say, pulled pork, meaning you can garden, hike, or whatever it is you do in the summer, without feeling sluggish.
Of course, shrimp do have problems on the grill. You want that charry Maillard-reaction flavor, but you also don’t want the little guys to overcook and turn rubbery. Shrimp that have that *snap* to them, that are juicy and tender are hard to get right unless you use some thermal thinking and a little bit of science. The key: using large shrimp and cooking them to the right temperature! We recommend shrimp be cooked to 120°F (49°C) for optimal juiciness, and with a fast and accurate Thermapen® Mk4, you can hit that temperature better than by simply eyeballing it. Read on for more details on how to perfect grilled shrimp.
Use Large shrimp for Grilling
Using the biggest shrimp you can get hold of is the first defense against rubbery, overcooked crustaceans. For grilling, try to never use anything smaller than 15-20 size shrimp (meaning there are between 15 and 20 shrimp per pound). The larger mass and size will act as a bit of a buffer against overcooking, giving you time to get those tasty grill lines on the outside. Also, use peeled shrimp. There’s not much use getting beautiful grill lines on your shrimp and then peeling off and discarding those lines.
Use Sugar When Grilling ShrimpIf you want that grilled, charred flavor on your shrimp, it’s going to need a little help. With a final temperature of only 120°F (49°C), you don’t have a lot of time on the grill to char things up before you hit your pull temp (a fact compounded by the small size of shrimp). A cheat to get around the slowness of the Maillard reaction is to introduce a little bit of sugar to the equation. No, we’re not sweetening the shrimp, just giving them a little help with browning/ caramelization. (If you’re thinking that Maillard-browning and caramelization are two different processes, you are correct. However, the complex flavors that arise from both of them are similar, they just have a different chemical mechanism for getting there.) Tossing your shrimp with a little bit of sugar will help them to brown without making a noticeable flavor difference.
Baking Soda for Better BrowningAnother way to cheat the browning process is to raise the pH of your food. Protein browning happens more readily, as does caramelization, at a higher pH, meaning that the same temperature can do more browning work with higher alkalinity. Adding a very small dose of baking soda raises the pH to help the added sugar, as well as the natural proteins, brown up faster without having to get as hot. (Incidentally, this is a great trick for caramelizing onions, too. A little sprinkle of baking soda brings about a much faster browning process.)
Pack Shrimp Tightly on Skewers Before GrillingAn individual shrimp sitting on a grill grate faces two serious dangers: it will probably fall through the grate, and if it doesn’t it has a very high probability of overcooking. After all, it’s just one tiny shrimp sitting there, surrounded by flame. (Have I mentioned yet that shrimp are easy to overcook on the grill?) To overcome both these hurdles, we need to think about how we situate our shrimp, and it turns out we should do it like sardines.
To get the best thermal situation for grilling shrimp, use two skewers and pack the shrimp tightly against one another with no gaps between them. Stagger the direction the shrimp face so that they stack well. By stacking them close together, we eliminate surface area that would be exposed to heat, we transform individual shrimp into a broad flat block of shrimp that will allow the heat to penetrate it more slowly. And because of the two skewers, that swath of shrimp easily be maneuvered and flipped without than flopping around, spinning on a single-skewer axle and falling through the grates.
Drier Shrimp Grills BetterHere’s a thermodynamic fact: water takes a lot of energy to convert to steam. And here’s a chemical fact: Maillard browning doesn’t happen well in the presence of excess moisture. So what happens if you put dripping wet shrimp on the grill and hope to get nice browning? You have to wait while the water boils off before browning begins, and you overcook the shrimp—heat is still going into the shrimp while you’re boiling the water off the surface, after all.
To ensure a faster sear, pat your shrimp dry with paper towels (preferably before mixing in the sugar and baking soda), then let them air-dry in the refrigerator for an hour before grilling. Suspending the skewers above a baking dish will provide all-around air circulation, drying the shrimp faster and better. After an hour of drying in the fridge, your shrimp are much more likely to sear well without overcooking.
Oil basteBut what if you want to add flavor to your shrimp before cooking? Our desire for drier-skinned shrimp precludes a wet marinade. The answer is oil. Some minced garlic mixed in with some oil and brushed onto the shrimp before grilling can bring loads of flavor to the dish and, as a bonus, the oil actually helps the shrimp to sear on the grill grates. A plain, neutral flavored oil will do fine, but olive oil or a flavored oil like a chili or lemon oil can add another dimension to the final dish.
Cook Shrimp on a Hot Grill to an Internal Temp of 120°F (49°C)
To get a fast, hard sear on your shrimp, you’ll need a hot, hot grill. If you’re using a charcoal grill, pile up a full chimney of hot coals under one half of the grill and cook over those coals. If you’re cooking with gas, turn your burners to full and let the grill heat up for at least 15 minutes before you cook (while your shrimp are drying in the fridge).
Brush your shrimp with oil and garlic, and toss the double skewers onto the direct heat. Let them stay on that first side for a solid 2–2 ½ minutes, then flip. Start checking the temperature with your Thermapen Mk4 immediately, looking for a pull temperature of 120°F (49°C). Total cooking time will be about 5 minutes. As each skewer reaches temp, pull it from heat and set it aside on a clean platter.
More:
https://blog.thermoworks.com/fish-seafood/how-to-grill-shrimp-temperatures-and-thermal-principles/
