Demi-glace, which comes from the French word that loosely translates to glaze or icing, is a foundation for many other sauces. Beef demi-glace is made by reducing beef stock with wine and sherry until it is thickened and flavorful. The traditional process requires beef bones and vegetables and can take all day. Thankfully there are commercial alternatives and a few ways to create a demi-glace substitute in a few minutes with ingredients that are likely already in your pantry.
High-End Demi-Glace Concentrates
Several companies offer demi-glace concentrates that can be reconstituted for sauces and other recipes that call for a demi-glace. These intensely flavored concentrates use real beef and veal stock mixed with carrot, onion and celery stocks, red wine, tomato paste, salt and veal and beef fat. They are available online and in gourmet food stores. Most of these concentrates should be refrigerated after opening. The reconstitution ratios vary some between brands, but usually 1 oz. of the demi-glace concentrate makes 4 to 5 oz. of liquid.
Low-End Demi-Glace Concentrates
Low-end demi-glace sauce concentrates cost less than half the price of higher-end concentrates due on account of the ingredients used. The main ingredient in most of these concentrates is modified food starch, followed by maltodextrin, cooked beef fat, partially hydrogenated soybean and/or cottonseed oils, concentrated beef broth, butter oil, salt, dextrose, hydrolyzed corn protein, whey, dried beef extract, tomato powder, autolyzed yeast extract and minute amounts of other ingredients.
Though beef stock won't have the depth of flavor or texture that beef demi-glace has, it will work as a substitute in some recipes, though not those that rely on the demi-glace for texture, as in sauces. Cooking the beef stock down will thicken the broth and intensify its flavor, more closely mimickng the texture of demi-glace. If you use beef stock instead of demi-glace, do not add any water called for in the recipe.
Demi-Glace Substitute Recipe
To create the equivalent of 1 cup demi-glace simmer 2 cups beef broth and 1 tpsp. of butter in a pan until the broth is reduced by half. Dissolve 1 tsp. of arrowroot or cornstarch in cold water and add to the beef broth, stirring constantly. Continue to simmer until the mixture is thickened. If the mixture is too thick, add sherry or balsamic vinegar 1/8 tsp. at a time, stirring after each addition until the sauce is the desired consistency.