Why do milk spoils easily?

Milk spoils easily due to its nutrient-rich composition, which provides an ideal environment for bacteria and microorganisms to thrive. The presence of lactose, proteins, and fats in milk can be broken down by these microorganisms, leading to off-flavors and spoilage. Additionally, exposure to heat, light, and air can accelerate the process by promoting bacterial growth and enzymatic reactions. Proper refrigeration and pasteurization can help extend the shelf life of milk by inhibiting this spoilage.