Pan-Seared Duroc Pork Chop, Demi-Glace and Mustard Sauce

Salt pulls water to the surface. In about 40 min the meat takes the brine back in. Chloride ions partly dissolve myosin. The fibres then hold more water when heat contracts them. The uncovered surface also dries. A dry surface browns fast. A wet surface steams.

Pork holds inosinate (IMP). MSG adds glutamate. The umami receptor responds to the two together much more than to either one alone. So 0.85 % salt tastes fuller than it is. This keeps the sodium low.

The time for heat to reach the centre increases with the square of the thickness. A 2.5 cm chop heats through in about 40 % of the time of a 4 cm chop. The centre reaches temperature during the sear, so a reverse sear is not necessary. A chop that comes from a low oven goes past the target during the sear.

Each turn moves the hot face away from the pan. That face cools a little while its heat moves inward. The other face then sears. The centre heats as if from two sides. The cook is faster and more even. The grey band under the crust stays thin.

Myosin sets at about 50 °C to 55 °C. This gives the texture. Actin contracts from about 66 °C. This pushes juice out of the meat. So start the baste at 55 °C, remove the chops at 60 °C, and let the rest finish at 62 °C to 63 °C. Duroc has high intramuscular fat. This fat melts in this range and keeps the meat moist.

Pork fat sits in cells inside a collagen network. Direct contact with the hot pan shrinks the collagen. The fat then runs out, and the remaining tissue becomes crisp. The rendered fat is the cooking fat for the sear.

The cider dissolves the browned residue from the pan. Its malic acid cuts the fat. The seed coat of mustard holds a mucilage that acts as an emulsifier. Cold butter whisked in off the heat stays as small droplets, and the sauce becomes glossy. Hot butter melts and separates.

Demi-glace is brown stock reduced until it sets when cold. Gelatin gives that set. In the pan the gelatin dissolves and the sauce coats a spoon after a short simmer. Gelatin also helps hold the butter in small droplets, so the emulsion is more stable than in a thin pan sauce. Further reduction makes the gelatin too concentrated and the sauce becomes sticky. Stop when it coats the back of a spoon.