灰汁

1. Origins, structure, and basic meaning

• Structure: 灰汁 (あく) can mean scum rising during cooking or the harsh, astringent quality of wild vegetables.
• Basic usage: 灰汁をすくった removes visible scum from a simmering surface; 灰汁を抜いて removes harshness by soaking the ingredient.

2. Common pitfalls and similar expressions

• Scum skimmed from a surface and harshness removed from food
  • Both examples mark it as an object, but すくう targets visible matter and 抜く targets a component or taste within food. The reading is あく, not a regular Sino-Japanese reading.