Green Coffee: Grading and Processing

Green Coffee Grading and Processing  

Coffee beans are a commodity.  Just like grading of fruit (Fancy, extra Fancy, Canada Fancy, Canada Commercial and others) coffee has a grading scale as well.   

Generally, the higher the elevation the bean is grown, the higher the quality and grading.  Equally, the larger the coffee bean, the higher the grading.    

Coffee traders use a graduated sifter scales to determine bean size. The screens all have different sized holes measured in increments of 1/64th of an inch. So a 15 grade coffee means that the hole sin the screen are 15/64ths around. Most green coffee is between grade 12 and 19.  This system can be done manually or with professional graders that use air pressure to sort the beans.   

Green coffee is also sorted based on colour and density.  These three elements make up most of the grading techniques for green coffee.  There are no universally accepted standards though and each country does things their won way with their own nuances. The main reason for this is language.   

Now that we have that out of the way, what are the actual grades?  There are tow grades that apply to green coffee: bean size and number of defects with the coffee.   

Bean Size Grading (remember the bigger the bean the bigger the grading):  

Africa: AA (the biggest beans), AB then A  

Columbia/Central America: Premium (largest), Supremo, Excelso, Peaberry 


Bean Height Grading (remember the higher the elevation the better the bean): 

Strictly Hard Bean (SHB) grown above 4500 feet above sea level and very dense 

Hard Bean (HB) grown between 4000 and 4500 feet above sea level 

Strictly Soft Bean (SS) grown under 4000 feet above sea level. 


Defect Grading: 

Grade 1: Specialty Coffee Beans.  This is the highest grade allotted and given to beans that have no inherent defects but are permitted up to three defect. There are no quakers (ie. unripe beans) in this grade. 

Grade 2: Premium Coffee Beans. This is a premium coffee bean and can have up to six defective qualities.   

Grade 3: Exchange Coffee Beans.   These are beans that are 50% above the screening level and should not have more than 5 Quakers. The large majority of supermarket coffee use this grade of beans and they can have between 9 to 23 defects. 

Grade 4: Standard Coffee Beans.  These are not good beans!  They won’t roast well or taste good.  They can have between 24 to 86 defects. 

Grade 5: Off-Grade Coffee Beans. The name says it all.  Good for fertilizer or maybe instant coffee (they’re the same thing, right?) 

So, what is the best you can buy?  The answer to that is the freshly roasted, local and high quality coffee of Chin Chin where we only use specialty grade, high elevation green coffee.