What chemical change occurs when you are making a beef stew?

The primary chemical change during beef stew preparation is protein denaturation and gelatinization of starch.

1. Protein Denaturation:

- Beef consists of muscle fibers primarily composed of the protein myosin.

- As you slowly simmer or cook the beef in the stew, the protein undergoes denaturation.

- Denaturation disrupts the bonds and structure holding the myosin protein intact, causing it to unfold and expose more of its surface area.

- This process tenderizes the meat and improves its texture.

- Other proteins present in vegetables and any added dairy (milk or cream) may also undergo denaturation.

2. Gelatinization of Starch:

- If your beef stew has added starch-rich ingredients like flour or potatoes, a significant chemical change involves gelatinization.

- As the stew cooks, starch granules absorb water and begin to swell.

- At a specific temperature (around 140° F / 60° C for most starches), the starch granules burst and the starch molecules further absorb water and release glucose units.

- This transformation forms a viscous, gel-like substance that contributes to the stew's characteristic thickness and consistency.