Analysis of the color change of milk foam in coffee machine during coffee bean roasting process

The color change of coffee beans is an important indicator of the roasting process. As the roasting temperature increases, the color of the coffee beans gradually changes from green to yellow, brown, and may eventually reach dark brown. During the roasting process, the water of the original green coffee beans evaporates and chemical reactions occur, causing the color of the beans to become lighter.

When the roasting temperature is further increased, the coffee beans will undergo the so-called "Maillard reaction" and caramelization process. These chemical reactions not only change the color of the beans, but also affect the flavor of the coffee. Lightly roasted beans are yellowish or light brown in color, while darkly roasted beans are dark brown or almost black.

By observing the color of coffee beans, coffee lovers and professionals can judge the degree of roasting. Light-colored beans usually retain more acidity and fruitiness, while dark-colored beans show more intense bitterness and caramelized flavors. Therefore, color is not only an indicator of the degree of roasting of beans, but also directly affects the taste experience of the final coffee.

Color comparison and flavor impact of light roasted and dark roasted coffee beans

Lightly roasted coffee beans are usually lighter brown or yellow-brown. This color change is mainly due to the reaction of sugar and amino acids inside the beans at low temperatures. Light roasting retains more of the original flavor of cafes, including fruity and sour flavors, and is suitable for coffee lovers who like a refreshing taste.

In contrast, dark roasted coffee beans are darker in color, often dark brown or even nearly black. This color change is due to a chemical reaction at high temperatures, which caramelizes the sugars in the beans and produces a burnt aroma. Dark roasted coffee beans have a richer flavor, with a distinct bitter and caramel flavor.

The color difference between light roasted and dark roasted coffee not only affects the visual experience of the beans, but also directly determines the taste level of the coffee. Choosing the appropriate roasting degree can be adjusted according to personal taste preferences to meet different drinking needs.