How does milk temperature affect microfoam quality?

Steaming milk to around 150°F is critical for achieving high-quality microfoam. At this temperature, the milk proteins begin to denature and stabilize the air introduced during steaming, creating a fine, velvety texture. This temperature is optimal because it allows the milk to maintain its sweet flavor while also providing the necessary conditions for microfoam creation. When milk is heated to this level, it becomes capable of incorporating air effectively without scalding the milk or compromising its natural sweetness.

While other temperatures may also create foam, varying significantly from this ideal can lead to less desirable results. For instance, higher temperatures can lead to larger bubbles and a grainy texture, while lower temperatures may not be sufficient to create the desired microfoam consistency. The process of steaming milk is essential for this transformation; without proper steaming, one cannot achieve the microfoam quality sought after in specialty coffee drinks.