What is the difference between roux and corn starch for gravy?

Roux and cornstarch are two common thickeners used in gravy, but they have some key differences.

Roux is a mixture of flour and fat that is cooked together to create a thick, smooth paste. This paste is then added to the gravy liquid, which is usually a combination of stock and water. The flour in the roux helps to absorb liquid and swell, creating a viscous sauce. The fat in the roux provides flavour and helps to prevent the sauce from becoming lumpy.

Cornstarch is a starch that is derived from corn. It is a fine, white powder that is typically used in small quantities to thicken liquids. Cornstarch creates a clear, glossy sauce and can be used to thicken both hot and cold liquids. It is important to dissolve cornstarch in a small amount of liquid before adding it to the gravy, as it can easily form lumps if added directly to the hot liquid.

Here is a table summarising the key differences between roux and cornstarch:

| Feature | Roux | Cornstarch |

|---|---|---|

| Appearance | Thick, smooth paste | Fine, white powder |

| Texture | Creamy | Clear, glossy |

| Colour | Brown | Clear |

| Flavour | Rich, savoury flavour from the fat | Neutral flavour |

| Use | Used to thicken sauces and stews | Used to thicken soups, sauces, and desserts |

| How to add | Mix with fat to create a paste, then add to the liquid | Dissolve in a small amount of liquid before adding to the hot liquid |

Ultimately, the best choice of thickener for gravy depends on the desired texture and flavour. For a rich, savoury gravy, roux is a good option. For a clear, glossy gravy, cornstarch is a better choice.