卵黄

1. Origins, structure, and basic meaning

• Structure: 卵黄 (らんおう) is the yellow yolk of an egg. It appears as mixing ingredient and separated part.
• Basic usage: Yolk is mixed with sugar for batter; it is separated intact from white.

2. Common pitfalls and similar expressions

• Ingredient mixed into batter and part separated from egg white
  • 卵黄と砂糖 coordinates ingredients; 白身から卵黄を marks source and object. It is not the whole egg.