Temperature matters. Whether you’re grilling a steak or cooking rice, ask
the chemical reactions in food occur in well-defined temperature ranges. One protein in steak, stomatology
myosin, begins to denature around 122°F, while another, actin, doesn’t do so until around 150°F. The starches in rice begin to gelatinize—absorb water and swell up—around 160-175°F.
Why is this important? Because it’s these reactions that we care about when cooking. The reason medium-rare steak is so, well, yummy, is because a large percentage of the myosin proteins are denatured (which changes its texture) while most of the actin proteins remain native. (There’s no general rule about denature protein having better texture; it just happens that we find the texture of meats with myosin denatured and actin native to be more pleasing.) With rice, the temperature has to get even hotter. This is why we don’t generally simmer lean meats in pots of rice: the meat would overcook before the rice has a chance to gelatinize.
Next time you step into the kitchen, take a minute to think about what effects you want to achieve. And keep in mind whether you’re roasting meat or grilling it, the proteins in the meat are going to undergo changes at the same temperature points, albeit a bit faster (and with a steeper doneness gradient) in the hotter environment of a grill. Instead of thinking about the temperature of the environment, think about the temperature of the food itself, and go from there.
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