Buttermilk (Best Option)
1 cup per 1 cup whole milkButtermilk contains lactic acid which helps break down proteins in meat, making it more tender and flavorful. Its consistency closely matches whole milk, ensuring the marinade remains balanced in moisture and texture.
For best results, use fresh buttermilk and ensure it is well mixed into the marinade. The acidity also helps the marinade penetrate deeper into the meat fibers.
Compared to whole milk, buttermilk imparts a mild tanginess and improves tenderness, making it an ideal substitute in savory marinades.