The quality of the coffee in the final cup depends largely on the state of the green bean. If green coffee is of low quality from the start, there is little a roaster can do to provide the best experience to consumers.
Defects in green coffee not only compromise the coffee's sensory attributes but can also cause roasters to lose contracts. This can have a domino effect, leading to financial problems and disruptions in business operations.
Normally, Green coffee goes through a grading process at source, and any defective beans are removed before export. However, some defects cannot be detected before roasting, while others may develop during transport or storage.
A physical inspection can help roasters detect defects in green coffee and inform them about the coffee's value and potential. It can also provide insight into how the beans will behave during and after roasting.
In this article, learn more about how to spot defects in green coffee just by looking at them.
Common coffee defects
Mold:
Coffee beans exposed to excessive moisture during the drying, roasting, or storage process can create conditions for mold growth, leading to unpleasant flavors such as musty and musty flavors in the coffee. These types of mold can develop and spread to other grains.
Insect damage:
These are coffee beans that have bites or holes caused by insect infestation. If there are many of these beans in your coffee batch, They will leave a sour or bitter taste, with an acrid and unpleasant flavor.
Full Black/Full Acid:
These defects occur when coffee cherries are picked either unripe or overripe. These grains are the result of excessive fermentation within the fruit before harvesting and processing. , resulting in a strong alcoholic fermentation flavor and a heavy sour vinegar flavor in the coffee.
Broken/Chipped/Cut:
It's a defect that occurs during processing, specifically during the hulling process. This makes the cut area more susceptible to oxidation, which can result in a decrease in quality. Additionally, having too many beans with this defect can cause uneven roasting , as broken beans are more likely to burn.
Quakers:
These are immature, unevenly ripe, or undernourished seeds from coffee berries during their development. During roasting, these seeds will lack sufficient chemical compounds to participate in the Maillard process, resulting in a lighter color compared to other beans from the same batch. Your coffee will lack sweetness and flavor if it contains too many quakers.
Shell:
This is the outer part of a strange object shaped like an elephant ear or seashell. This is the result of a mutation in the coffee bean. This type of bean doesn't directly impact the flavor; however, it has a thin, flat structure, which makes them the first beans to burn when roasting coffee.
Stones, dry pods and branches:
These are foreign objects that can appear in your coffee if the previous processing steps didn't meet standards. Stones can cause damage to machinery during the roasting and grinding process; broken coffee husks can easily ignite and cause smoke and a burnt smell in the roasting chamber; and finally, twigs and branches can add an unpleasant taste or flavor to your cup of coffee.
Preventing defects in green beans certainly involves following good production practices, careful soil management, and harvesting at the right time. Therefore, it 's important to research suppliers in advance.
Whether you're just browsing or roasting coffee at home for pleasure, be sure to watch out for these defects. Keep your storage systems clean and dry to maintain bean quality.