What is the purpose of blanching bones (pre-boiling and discarding the water) before making certain stocks, and in what cases is this done?

Question

Learn the purpose of blanching bones for stock. Find out why this pre-boiling step is used in certain recipes to achieve a cleaner, clearer result.

Answer 1

Blanching bones removes impurities like blood and marrow, resulting in a clearer, cleaner-tasting stock. This is commonly done when making light-colored stocks like chicken or veal stock.

Detailed Explanation:

Blanching bones is a crucial step in stock-making, particularly for lighter stocks, as it significantly impacts the final product's clarity, flavor, and aroma. Here's a breakdown of the process and its benefits:

1. Purpose: The primary goal of blanching is to remove impurities from the bones. These impurities include:
   • Blood: Blood contains proteins that can coagulate during the stock-making process, leading to a cloudy appearance and potentially off-flavors.
   • Marrow: While marrow can add richness, it can also contribute to a greasy or muddy flavor if not properly handled. Blanching helps to remove excess marrow.
   • Other Proteins and Debris: Blanching helps remove any other surface impurities that might be present on the bones.
2. The Blanching Process:
   1. Place the bones in a large pot and cover them with cold water.
   2. Bring the water to a boil. As the water heats, impurities will be released from the bones and rise to the surface as scum.
   3. Once boiling, let the bones simmer for a short period, typically 5-10 minutes.
   4. Drain the bones and discard the blanching water. Rinse the bones thoroughly under cold water to remove any remaining impurities.
3. When to Blanch: Blanching is most commonly used when making:
   • Chicken Stock: Blanching chicken bones results in a cleaner, brighter-tasting stock, ideal for delicate sauces and soups.
   • Veal Stock: Similar to chicken stock, blanching veal bones produces a lighter, more refined stock.
   • Light-Colored Stocks: Generally, if you're aiming for a clear, light-colored stock, blanching is recommended.
4. When Not to Blanch: For darker stocks like beef stock or brown stock, blanching is often skipped. In these cases, the bones are typically roasted before being simmered, which develops a deeper, richer flavor. The impurities are often considered part of the desired flavor profile in these stocks.

Pro Tip:

After blanching and rinsing the bones, consider roasting them briefly before adding them to the stockpot. This adds a layer of depth and complexity to the flavor of your stock, even if you're aiming for a light-colored result.