Demi-Glace
The same record, read as a method. This page holds the reasoning; that one holds what to do.
NN-SC · demi-glace
Study
Science · StudyScience · Study
Demi-Glace
Classical demi-glace with a dual-bone foundation, triple clarification and a staged reduction. A preparation other recipes pull in rather than a dish.
Mechanisms
oneM1
Why each layer exists
The dual bone foundation is doing three separate jobs: marrow for fat and mouthfeel, veal knuckle for gelatin, oxtail for concentrated meatiness. Dropping any one of them is a real loss rather than a simplification. The triple clarification is likewise three different mechanisms — mechanical, protein raft, adsorption — not the same step done three times.
The method
One recipeApplied in
five recipesBeef Wellington: Moisture Control as the Whole Problem
Research on why Wellingtons fail and what the techniques that fix them are actually doing — octagonal searing, duxelles dehydration, layered moisture barriers and two-stage baking.
First revisionMixed-Bone Brown Stock
A brown stock made for the braise of the South African pepper steak pie. Beef bones and marrow bones roast first. A freezer mix of chicken carcass and lamb saddle bones goes in for the last 20 min. Tomato paste, onion and celery brown on the trays for the last 10 min. The bones then go into cold water. The stock comes up slowly so the foam can be removed. It holds at a light simmer of 88 to 90 degrees C overnight, with the lid off. The stock has no salt. The braise reduces it, so the salt goes in there. It makes about 3 litres.
First revisionPan-Seared Duroc Pork Chop, Demi-Glace and Mustard Sauce
Bone-in Duroc chops, 2.5 cm thick. Dry-brine with salt and MSG for 45 min. Render the fat cap on its edge. Sear in the pan and turn every 30 s to 55 °C. Baste with butter, garlic and thyme to 60 °C. Rest to 62–63 °C. Make a demi-glace and wholegrain mustard sauce in the same pan while the meat rests.
Second revisionSauce Périgueux Spaghettini with Seared Duck Breast
Sauce Périgueux is the classical French truffle sauce. It is built on demi-glace, not on butter. Here it dresses spaghettini, and a seared duck breast goes beside it. The truffles are jarred pieces in oil. They go into the sauce off the heat, because their aroma compounds are volatile. Pecorino goes on top for acidity. A rocket salad with lemon cuts the richness.
First revisionSouth African Pepper Steak Pie
The South African garage pie, made as individual pies in 120 mm foil tins. Shin cubes and oxtail are dry-brined overnight, browned in the oven and braised for 3 h in a reduced mixed-bone stock, reduced merlot and demi-glace. Shin tendons cook whole in the stock overnight, then go into the filling. The braising liquid chills overnight, loses its fat cap and is reduced until it sets firm. No starch goes in. The filling is portioned into 200 g pucks and frozen. Each pie gets a frozen puck in a puff pastry case, baked on a hot baking steel. The thin foil and the frozen filling keep the base dry with no blind bake. Bake 6 at a time and keep the rest of the pucks frozen. Black pepper goes in twice: on the meat before browning and into the finished filling.
Second revision