Is there something like perfect coffee? All we do as baristas or roasters is aim for this perfect cup. What can be considered as perfect? Is the perfection always the best? Let’s find out.
I personally strongly believe that imperfections are far more interesting. You can see this, for example, in art or fashion. In coffee, this diversity of bean size or color or even defects is what gets me excited. I’ve cupped thousands (if not more) of coffees, both as samples or simple QC. To be honest, the most exciting times are when I cup something unexpected. It can be super floral Guatemalan coffee that is a decent caturra variety or even a phenolic cup in one of ten roasts of the same coffee. It’s not always tasty, but it just happens. I always see it as an opportunity to train my palate or discuss my excitement with coworkers or friends.
How does it happen that coffee is not always perfect? The answer is super simple – coffee is a fruit. As an agronomy product, it can have differences because of many reasons. As 88 Graines, we are asked mostly about differences in sizes between beans, differences in color of raw and roasted coffee, as well as coffee defects.
The size of the beans is a complex topic. It is affected in different stages of the coffee journey. First, coffee fruits, aka cherries, are grown on a plant, and they can have different sizes. Simple. Like any other fruit, their bean can have different sizes as well. The overall or average size of the bean depends on the variety (Java will have small beans while Maragogype will be massive), but it can be affected by weather conditions before harvest and during one. For example, droughts can decrease the size of beans.
Then we have picking. It is mostly done by people. Currently, many Central American countries struggle to find workers for their harvest. This is reflected in less selective picking and fewer passes through coffee trees to find only ripe cherries.
When picked, coffee goes to a processing plant or wet mill. It’s then sorted for floating, removes most of the defects, fermented, and sometimes sorted by density while washing the mucilage. After that, coffee parchment or dry cherries are transferred to a dry mill, where it’s sorted by machines. They usually sort them for density, size, and color.
This process is expensive, especially for European preparation (EP), which is the highest standard of sorting. To mark it as EP coffee, it must be screen 15 and above and can have only eight defects in a 300-gram sample. For comparison, American Preparation (AP) allows screens 13 and above with 23 defects in a 300-gram sample.
Differences in the color of beans are something you often ask about.
Washed coffee is uniform in color due to fermenting as a batch underwater that unifies microbiological activity throughout all beans. Natural and experimental processing is a completely different story. Drying whole cherries is a big challenge. It takes longer, which means that yeasts that are naturally there have more time to ferment mucilage, and every bean is fermented on its own. This phenomenon can result in differently colored raw beans.
Some of you also ask us about quakers and differently colored beans after roasting.
For naturals, it’s usually the same reason as differently colored raw beans. Quakers are slightly different. They are mostly undetectable in green material. Most are sorted while processing as floaters, but some still make it through. Quakers, in simple words, are nothing more than seeds that don’t have enough sugars to go through Maillard reactions (which require reducing sugars and amino acids). It can be caused by not having enough sugars developed during the maturation of fruit or a different stage of fermentation (that also requires sugars). Quakers are less of an issue when you roast your coffee very dark than caramelization, and „burning” will even out the color.
The last part is the defects. Here, we need to consider what is a defect.
I strongly believe, as a Q grader, that if there is no definition of your weirdly looking bean in the „Green coffee defect handbook,” it is not a defect. Period. CQI and SCA have their own definition of how many defects of the different categories you can get in the 350-gram sample, but remember that they always refer to a random 350-gram sample, not a 2 kg batch or a full sack of coffee.
I’ve mentioned that imperfections are far more interesting. Let’s take advantage of them. Small differences in bean size can build more complex cups. Small beans will roast slightly faster, which will result in sweeter tones in a cup, and bigger beans will be lighter in color inside, which will result in a more fruity character in the cup. I think it is fascinating! If your beans are very different in color, it can be a challenge for you. To even out the color, it’s good to stretch roast and development time. Meaning lower end temperature and longer development time. This will give beans more time to process sugars and will even out the color. Defects? Can you taste them? Try it and look for them, let it be an exercise for your tongue and nose or an amazing opportunity to show off to your customers, coworkers, or friends. They will see you as an amazing expert who can detect and name particular defects.
If you’re still curious about this topic, feel free to email us with your questions. Have fun roasting!
Our step-by-step roasting guide & roasting tips has been design for you by Aleksander Smet, 2022 Polish Roasting and Cup Tasters Champion.
Roast Breakdown - Development
