The first crack refers to the first popping sound which coffee beans make when in the process of roasting.
The reason why it cracks if that moisture trapped inside the beans expand and burst out after being heated.
After being roasted for a while, it cracks open with a snap and it’s size appears to grow.
Evenness when used of beverages, especially coffee, describes the uniformity of everything from dose, to grounds, to the actual espresso, etc.
For example, a low quality grinder can result in grinds that are inconsistent in size and texture in a single dose. In this case, it has undesirable evenness.
A coffee that was not agitated might have residue products in the drink itself. This can be deemed as an uneven cup of coffee.
The dose is a term used to refer to the amount of coffee ground used to prepare a serving of coffee.
As different cafes or baristas would have their own recipes, it is no surprise to find that there is no standard dose used by the majority of cafes.
Even different espresso machines might require different doses for brewing due to the manner in which they are built to operate.
A density table is a piece of equipment used to sort higher quality coffee beans from regular beans.
Sometimes also referred to as the Oliver table, density tables are slightly tiled and use vibration that causes beans to move about.
The logic is that denser beans would move to the top side of the table while the less dense ones move to the bottom.