regular or low-fat milk

Milk is a nutrient-dense liquid secreted by the mammary glands of lactating mammals, most commonly from cattle (Bos taurus) in commercial contexts. Regular whole milk contains approximately 3.5–4% fat by volume, while low-fat milk (also called 2% milk) contains 2% fat, with fat-soluble vitamins adjusted accordingly. Milk is composed primarily of water, lactose (a natural disaccharide), casein and whey proteins, and butterfat, along with essential minerals including calcium, phosphorus, and potassium. The flavor is mild, slightly sweet, and creamy in whole milk, becoming increasingly thin and less rich as fat content decreases. Pasteurization (heat treatment) is standard in most commercial supplies to eliminate pathogens while preserving nutritional content and shelf stability.

Milk may originate from various dairy animals—goat, sheep, buffalo—but cow's milk dominates global commerce due to yield and established infrastructure. Regional variations exist in fat content, breed-specific milk characteristics, and processing methods (such as A1 versus A2 protein variants).

Milk functions as both a primary ingredient and a fundamental baking and cooking medium across virtually all culinary traditions. In baking, it provides moisture, richness, and structure in breads, cakes, custards, and pastries; it also activates baking soda when acidic components are present. In sauce-making, milk forms the base of béchamel and other mother sauces in French cuisine. It is essential in puddings, ice cream, yogurt, and cheese production. Low-fat milk performs similarly but yields lighter textures and reduced richness in cream-based dishes; whole milk is preferred when maximum body and richness are desired. Milk pairs naturally with grains, eggs, chocolate, fruits, and vanilla.