When two café owners ask each other about the grade of beans they use, what lies behind the question is a complex international coffee grading logic. Brazil's defect-point system, Central America's altitude standards, East Africa's screen sizes—each producing country has developed a completely different quality evaluation system based on its own national conditions. This article will systematically sort out three mainstream grading methods: by growing region altitude, by green bean screen size, and by a composite evaluation method combining screen size and defect bean ratio, and will explain in detail Brazil's unique three-part grading system and its strict cupper culture. Whether you are a beginner enthusiast or a seasoned professional, understanding these standards can help you judge coffee quality more accurately and also provide a reference for everyday purchasing.

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Suppose two café operators are chatting. The owner of Shop A says, "We use Brazil Santos NO.2, what about you?" The owner of Shop B replies, "We chose Brazil NO.1, the same grade as Blue Mountain NO.1."

Brazil uses a "defect-point" evaluation method. Specifically, it counts how many defective beans are mixed into every 300 grams of primary beans to determine the grade. Grades range from NO.2 all the way to NO.8, seven levels in total. If the defect points are less than 4, it is classified as NO.2 (while NO.8 corresponds to as many as 360 defect points). In theory, a lot completely free of defective beans could be called NO.1, but such cases are extremely rare and stable supply simply cannot be guaranteed, so Brazil sets NO.2 as the highest grade rather than NO.1. From this we can see that the owner of Shop B was merely putting on airs.

In order to grade the coffee they harvest, each coffee-producing country has established its own grading scheme and quality evaluation standards (though there are also countries like Yemen that produce the famous Mocha Mattari coffee but have no unified export specifications). If all bean-producing countries in the world could share a single evaluation system, it would undoubtedly save buyers a lot of trouble. Unfortunately, current grading standards are still based on each country's specific national conditions.

Even so, we can still make a rough distinction according to the following three directions.

(1) Grading by the altitude of the growing region

(2) Grading by screen size (green bean size)

(3) Grading by screen size and defect bean ratio

1. Evaluating quality by the altitude of the growing region

As mentioned earlier, coffee produced in high-altitude regions is superior in quality to coffee produced in low-altitude regions, so growing region altitude has also been included as one of the indicators of quality evaluation. The higher the altitude, the relatively lower the temperature, and the coffee fruit matures slowly; beans that develop fully in this way expand well and are easier to roast. For this reason, the coffee-producing countries of Central America almost all judge coffee bean quality solely by the altitude of the growing region.

Take Guatemala as an example. The country's highest-quality coffee is named SHB, the abbreviation of Strictly Hard Bean, grown in areas above 1,350 meters in altitude. Mexico is the same: its highest quality grade, SHG (Strictly Hard Grown), requires cultivation in highlands above 1,700 meters. El Salvador and Honduras also require SHG to be grown in highlands above 1,200 meters.

If the coffee growing area is a flat plateau like Brazil's, mechanized operations can be carried out on a large scale. But the main coffee-producing regions of Central American countries are mostly located on mountain slopes, where mechanized farming is extremely difficult to implement. It is said that the Jamaican Blue Mountain region even has steep slopes with gradients exceeding 40 degrees.

Farming on such terrain can only rely on manual picking, carefully plucking each ripe red fruit one by one. Although labor costs are relatively high, it can produce high-quality coffee with very few impurities and defective beans.

The quality and grading of Guatemalan coffee beans

2. Evaluating quality by screen size

Countries that use screens to judge quality include Kenya, Tanzania, Colombia, and other producing countries of Colombian mild coffee (one of the coffee types traded on the New York futures exchange by place of origin). Judging quality by screen means evaluating quality according to the size of the green beans. Various green beans are sized by passing them through iron disc screens with holes.

The unit for screen hole size is 1/64 inch, so screen No.17 means 17/64 inch, that is, green beans that can pass through a screen with holes 6.75 mm in diameter. Beans larger than this size cannot pass through the screen, while smaller ones can. Therefore, the larger the screen number, the larger the bean size.

Tanzania's highest-grade coffee beans are large beans called AA, which require a screen of No.18 (7.14 mm) or above; Kenya's AA likewise requires large beans that pass through screens with holes of 7.2 mm or more. Colombia has two grades, Supremo and Excelso. Supremo requires a screen of No.17 or above, while Excelso uses screen 14/16 (meaning among beans of screen No.16, 11% are screen No.14 beans).

Large beans are richer and more varied in flavor than small beans. Beans screened at different sizes do indeed differ in taste.

3. Evaluating quality by screen size and defect bean ratio

Next, look at Brazil, a major coffee country. It combines three grading methods—defect bean ratio (defect-point method), screen size, and taste testing—and from this developed the third evaluation method. For example, when buying Brazilian coffee beans, you often see a label like "Brazil Santos NO.2, Screen 19, Strictly Soft." Its meaning is as follows:

· Brazil—name of the producing country

· Santos—port of export

· NO.2—a grading method indicating the quantity of mixed-in defective beans. NO.2 is the highest grade, while NO.8 is the lowest limit for export sales specifications.

· Screen 19—indicates bean size. Brazil uses 12-20, and the larger the number, the larger the bean. 19 indicates beans that pass through a screen with holes of 7.54 mm. However, this grading method applies only to flat beans; round beans must be graded using special oval-hole screens (8-13).

· Strictly Soft—indicates the cup testing grade. Strictly Soft represents the highest level.

Brazilian-style cup testing grading method:

Grade 1: Strictly Soft

Grade 2: Soft

Grade 3: Softish

Grade 4: Hard

Grade 5: Rio (light iodine flavor)

Grade 6: Rioy (strong iodine flavor)

Grades 1-3 here are collectively called "Soft": sweet, bitter, and sour flavors are balanced, making it a quite mellow, good-quality coffee. In contrast, Grades 5 and 6 are inferior products with an iodine odor. The soil around Rio de Janeiro in Brazil has a strong iodine flavor; when coffee fruits fall onto this soil during harvesting, they pick up this distinctive taste.

This three-part grading method used by Brazil has never been adopted in other countries, because there is no need. In other words, even without "cup testing," one can know that these coffees have a certain quality. The reason Brazil uses this "cup testing grading method" is that its producing regions are too large and it produces too many beans. In order to blend coffee flavors exclusively for export, these coffee beans are often mixed together, resulting in inconsistent quality, which requires "cup testing" for grading.

For this reason, Brazilian coffee cuppers must observe strict requirements: in order for taste and smell to function fully when evaluating coffee, these cuppers must not only be free of cavities, but also must not eat foods that numb the tongue, such as chives, onions, and garlic; tobacco, alcohol, strongly scented perfume, and the like are of course also forbidden. In front of Zen temples there are often stone pillars inscribed with "No meat or alcohol beyond this mountain gate." Here, "meat and alcohol" refers to strongly flavored green vegetables such as chives and scallions, as well as alcohol. Brazilian coffee cuppers are like Zen monks, mainly eating vegetarian food every day.

In addition to the three grading methods mentioned above, some regions, like Jamaica, use classification by cultivation area.

The grading methods of various producing countries are diverse, and remembering them all takes a bit of skill, but once you are familiar with them, there is nothing much to it. In short: "Highland-grown, large-bean coffee without defective beans is good coffee."

The quality and grading of Brazilian coffee beans (points are deducted according to the amount of defective beans and impurities mixed into every 300 g of coffee beans, and the beans are then divided into NO.1 to NO.8 based on the deductions)

The above content is compiled by CoffeeHunters, a coffee news website.