Milk + Lemon Juice (Best Option)
1/4 cup milk + 1 tsp lemon juice per 1/4 cup buttermilkMilk combined with lemon juice mimics the acidity and moisture content of buttermilk, which helps break down egg proteins slightly, leading to a tender and fluffy omelette. The acid also adds a subtle tang that enhances flavor.
To ensure success, mix the lemon juice into the milk and let it sit for 5 minutes before use to allow curdling. Use whole or 2% milk for best texture; skim milk may result in a less rich omelette.
Compared to buttermilk, this substitute maintains the balance of acidity and moisture without adding extra fat, resulting in a similar fluffy texture and mild tang.