If you intend to make a very concentrated stock (a demi-glace or glace), how do you modify the stock-making process?

Question

Want to make a super-concentrated stock or glace? Learn how to modify the standard process to create an intensely flavorful reduction.

Answer 1

To make a concentrated stock like demi-glace, use a higher ratio of bones to water, simmer for an extended period, and repeatedly strain and reduce the liquid to intensify the flavor and collagen content.

Detailed Explanation:

Creating a concentrated stock requires a few key modifications to the standard stock-making process. The goal is to extract as much flavor and gelatin as possible from the bones and then concentrate that flavor through reduction. Here's a step-by-step breakdown:

1. Increase Bone-to-Water Ratio: Use significantly more bones relative to the amount of water. A good starting point is doubling the amount of bones you would typically use for a standard stock. This ensures a richer, more flavorful base.

2. Roast the Bones (Optional but Recommended): Roasting the bones before simmering adds depth and complexity to the flavor profile. Roast them at a high temperature (around 400°F or 200°C) until they are deeply browned. This caramelization contributes to a richer, more intense flavor in the final product.

3. Use Mirepoix Judiciously: While mirepoix (onions, carrots, and celery) adds flavor, use it sparingly. Too much mirepoix can overpower the pure bone flavor you're aiming for in a concentrated stock. A ratio of 2 parts onion, 1 part carrot, and 1 part celery is a good starting point, and consider using only half the amount you would for a regular stock.

4. Simmer for an Extended Period: A longer simmering time allows for maximum extraction of collagen and flavor from the bones. Simmer the stock for at least 8-12 hours, or even longer for larger batches. The longer the simmer, the richer and more gelatinous the stock will become.

5. Skim Frequently: During the simmering process, impurities will rise to the surface. Skim these off regularly to ensure a clean, clear stock. This step is crucial for achieving a high-quality demi-glace.

6. Strain Thoroughly: After simmering, strain the stock through a fine-mesh sieve lined with cheesecloth. This removes any remaining solids and ensures a smooth, clear liquid.

7. Reduce Repeatedly: The key to demi-glace is reduction. After straining, return the stock to a clean pot and simmer it gently until it has reduced to a fraction of its original volume. This process concentrates the flavors and gelatin, resulting in a rich, glossy sauce. You may need to repeat this process multiple times, skimming any impurities that rise to the surface.

Pro Tip:

Avoid adding salt during the stock-making process. The reduction will concentrate the salt as well, and you want to be able to control the final seasoning when using the demi-glace in a sauce or dish. It's always better to add salt at the end.