How can you tell if milk has curdled?

- Smell test: Milk that has curdled will have a sour or unpleasant odor. Fresh milk has a naturally sweet and slightly creamy scent, while curdled milk will have a distinctly sour or off smell.

- Texture test: Curdled milk will have a lumpy or grainy texture. Fresh milk has a smooth and consistent consistency, while curdled milk will feel bumpy due to the formation of small curds.

- Visual test: Curdled milk may have a change in appearance. Fresh milk is typically white or off-white in color, while curdled milk may appear yellowish, greenish, or even slightly pinkish. Additionally, curdled milk may separate into two layers, with the curds floating on top of the liquid whey.

- Taste test: While curdled milk is generally safe to consume, it may have a sour or unpleasant taste. Fresh milk has a sweet, creamy, or slightly salty flavor, while curdled milk will taste sour or acidic.

- Acidic reaction: If you place a drop of curdled milk onto a clean, dry surface and it forms a raised bump or mound that spreads as the liquid seeps out, it's a sign of curdling. Fresh milk will absorb into the surface and won't form such a distinct reaction.