Coffee roasting distinguishes coffee raw beans from defective beans

Beans with average shape, thickness, size, color, extension of the central line, etc., are the best.

Washed Arabica raw coffee beans must be uniform and glossy in appearance, and should not be uneven or dull in color.

The colors of raw beans are cyan, brown and other colors, and the color of beans represents water content. Cyan means more water, brown almost white means less water.

Screening is usually hand-selected.

Types of defective beans:

Moldy beans, dead beans, immature beans, shell beans, worm-eaten beans, black beans, cocoa, shell beans, stones, etc.

Moldy beans: due to incomplete drying, or too wet in the process of transportation and storage, cyan and white emblem bacteria grow, which will make coffee mildew.

Fermented beans:

A: the soaking time in the washing fermentation tank is too long, which is formed by the pollution of the washing water.

B: it is stacked in the warehouse, so it is attached by bacteria, and the surface of the beans becomes mottled.

It will make the coffee rotten.

Dead beans: beans with abnormal results, the color is not easy to change due to baking, easy to distinguish. If the flavor is thin, it will become the source of peculiar smell.

Immature beans: beans that are picked when they are immature and have a fishy, disgusting taste.

Shell beans: produced by poor dryness or abnormal mating, the beans break from the central line and the inside is turned out like a shell. It is easy to make beans baked unevenly.

Moth-eaten beans: moths invade and lay eggs when the coffee fruit is ripe and turn red, and the larvae eat the coffee fruit, leaving traces of moth on the bean surface. Worm-eaten beans will cause the coffee liquid to be cloudy and produce a strange smell.

Black beans: beans that ripen early and fall to the ground and ferment and blacken due to long-term contact with the ground will produce a rotten smell and turbidity.

Cocoa: it is caused by natural drying that the pulp remains and is not fully shelled. With the taste of iodine, soil, etc.

Shell beans: endocarp covers the inside of the pulp of coffee beans, and mostly remains on washed coffee beans. It has poor heat permeability during baking and sometimes burns, which is the reason for the astringent taste of coffee.