Buying Pergamino Coffee
The coffee bean goes through many processes before it can be brewed and enjoyed in your cup! After the cherries have been processed and dried, the coffee is then ready to be taken to be milled, but before this, coffee buyers and farmers alike need to know more about the quality of their green pergamino coffee beans.
Unless the coffee comes from a specialty coffee lot, size and uniformity determine a coffee’s market price. Though in reality, the size of the bean has very little to do with the end flavor of the coffee.
This coffee buyer’s guide will explain how Colombian coffee is assessed and rated before it is taken to be roasted.
What Is Pergamino Coffee?
Coffee graders in Colombia start with a sample of pergamino or parchment coffee. This is coffee that has been dried but not milled in a threshing machine. The term pergamino refers to the outer paper-like layer that covers the coffee bean. The pergamino coffee sample should have a humidity percentage that ranges between 10 % – 12 %. Coffee with higher humidity needs to be dried further before being stored and graded.
Coffee Humidity Test
250 grams of pergamino coffee is taken to sample and test the humidity of the beans. The sample is weighed, and then the humidity of the sample is measured. This step is done through a humidity determiner.
The coffee is sampled two to three times and then averaged. This guarantees that it is well within the correct range. High humidity puts the coffee at risk for common defects, including rest or alcoholic processes in storage, which can cause more serious defects like phenols.
If the humidity level indicates that the coffee is too dry, the shelf life of the bean will be shortened since it needs some humidity to survive! This is because green coffee is a living seed until it is roasted.
Observing Pergamino Coffee
The next step is to observe the physical appearance and uniformity of the parchment coffee. By looking at the uniformity of the beans with the naked eye, we have a good idea of the number of defects present in the sample.
Three characteristics related to pergamino coffee and its uniformity
- The coffee that is uniform does not have a defect at first glance.
- Slightly uneven coffee has very few defects.
- And the uneven coffee is full of defects.
After this step, the coffee is taken to be threshed or milled to remove the pergamino from the bean. This process is done with a laboratory-grade machine. The threshing machine facilitates the analysis starting from the time we enter 250 grams of dry parchment coffee. We obtain the green coffee without the shell and remove the cisco without losing any grain for the analysis.
Coffee Grain Size and Sorting
The grain size is important for producers. For Colombian coffee to be recognized and exported under the FNC, the coffee must be a certain size. Different-sized sieves are used to identify the size of the coffee beans. Excelso coffee refers to coffee that falls between the 14-16 inch aperture. Supremo refers to coffee with mesh sizes 17 and up. Different-sized sieves are used to identify the size of the coffee beans.
The Coffee Yield Factor
The yield factor is an assessment that takes into consideration the percentage of coffee lost due to defects. Removing the defective beans and leaving the sample as an excellent coffee or export type coffee that complies with the regulations of the National Federation of Coffee Growers of Colombia so the coffee can be exported as a certified Colombian Coffee.
Here is the formula we use to find a coffee’s yield factor = initial weight (0.250 kilos) * the constant (70 kilos) / amount of excelso of the sample (0.2014 kilos) = Performance factor of 86.89 (paid by arroba today, Monday 21, June at COP 158,270, $42.42 or $1.6972 per pound).
Currently, in Colombia, the yield factor is 94, which means we need 94 kg of dry pergamino coffee to produce one 70 kg bag of green coffee without defects. Grave (excellent export type coffee or Colombian Coffee).
The yield factor is used when negotiating a coffee or knowing its quality. For example, today, Monday, June 21, the price paid for 1 arroba (12.5kg) of dry parchment coffee with a yield factor of 94 comes out to COP 149,550 or $39.59 per arroba or $1.5638 per pound of dry pergamino coffee.
Price Per Arroba (12.5 kg pergamino coffee)
Coffee with yield factors below 94 is considered very profitable and is rewarded on the base price.
On the other hand, if the coffee has a yield factor above 94, it is penalized and would be worth a little less. We can see this by comparing the price paid per pound of dry pergamino with a factor of 94 and a pound with a factor of 86.89.
The physical defects that may be affecting the sample are divided into 14 groups; some of them affect the cup more; those of the first group are those defects that affect the cup, and those of the second group affect the cup but to a lesser degree.
Once the group and the yield factor determine the defects, the green coffee beans that have passed as Excelso graded coffee are taken to be roasted.