โญ Plant-Based Milk + Lemon Juice or Vinegar (Best Dairy-Free Option)
1 cup unsweetened soy or oat milk + 1 tablespoon lemon juice or white vinegar (let sit 5-10 minutes)The acid in lemon juice or vinegar curdles plant-based milk, creating a buttermilk-like acidic environment necessary for baking soda activation. Soy and oat milk have protein content closer to dairy milk, aiding texture.
Allow the mixture to sit for 5-10 minutes before use. Avoid nut-based milks if nut-free is required.
This substitute maintains moisture and rise but imparts a subtle difference in flavor and crumb compared to dairy buttermilk.