The El Manzano Project: Second Edition

    The El Manzano Project is an experimentation project that has identified approximately 11 variables of production within coffee processing; seeking to measure the effects of each variable on the final cup quality. 

    The First Edition, 2010-2011 Harvest, isolated and observed three of those variables, while maintaining the consistency of all other variables of production. The first part was in determining a method of categorizing and grading coffee cherries received at the mill, which we titled the Categorization Process. This is a foundation for all future experiments and measurements, identifying the initial quality of coffees submitted by producers, and helping us to determine its effects on the final cup. Secondly, we looked into the effects of different varietals of coffee, planted during the same year, and harvested five years later, each on the same day. The varietals consisted of Pacamara, Yellow Bourbon, and Red Bourbon, all planted side by side within distinct plots, at an elevation of 1,300 meters. A third experiment measured the effects of wet mill processing methods on the final cup quality, harvesting red bourbon from the same plot and day, and processing it four different ways, the Fully Washed, Mechanically Washed, Pulp Natural, and Full Natural processing methods. Each of these processing methods. 

    These experiments within the First Edition, were performed on a scale that provided us with the volume and consistency to reach conclusions, which we have begun to both publish and present to a distinct audience, which included independent roasters, national entities such as the Roaster’s Guild, and International Conventions, such as Let’s Talk Coffee, El Salvador. These showcases provided us with further reviews, feedback, and conclusions toward our initial goals in experimentation. 

    The Second Edition, 2011-2012 Harvest, is an expansion to the experimentation that has already begun, further measuring the variables of production, and how they influence cup quality. This edition will begin with examining the influence that drying methods play in the final cup quality.

Background for Experimentation

    In El Salvador, as well as much of Central and South American, patios are used for drying coffee. Coffees, after being washed of their pulp and mucilage, are spread out onto clay or cement tile patios, and stirred with wooden rakes once every hour, typically from sunrise to sunset, allowing the sun to dry the coffees to a moisture content of approximately 11.5 percent, at which point they are bagged, to rest for 30 days, before being hulled and exported. 

    In much of Africa, the prominent method of drying is with beds, or tables. These are typically wire screens built onto wooden or metal beams, or supports, and raised off of the ground to enable coffees to dry in the sun, while allowing air to pass on both sides, and circulate both above and below the coffee. 

    An additional method, contributing to the traditional methods around the world, is the mechanical drying method, where coffees are deposited into either a horizontal or vertical mechanical dryer, and dried with the heat generated by furnaces. These dryers circulate coffees throughout the internal cylinders and, retaining a consistent temperature, are much more time effective, as they enable coffees to be dried 24 hours a day. Mechanical dryers are also protected and not affected by rains and cloudy skies, which can prevent a coffee remaining on the traditional patios and beds, from drying quickly enough. 

Basis for Experimentation

    Considering the various methods for drying coffees, and the many opinions and discussions regarding which is the most efficient, and which produces higher quality coffees, Cuatro M, sets out to analyze and document the effects that different drying methods have on the same coffees. 

Underlying Question

Does one drying method produce a superior cup quality?


-To measure, analyze, and document the extent to which drying method determines the final cup quality of a batch of coffee, for both HG and SHG Coffees.

-To document and publish findings in an understandable and objective manner. 

-To present our findings within an environment that allows for feedback, discussion, and interactive cupping of the experimental coffees. 

-To promote research as a means of increasing understanding, appreciation, and respect for the processing level of the coffee industry. 

Timeline for Experimentation

November 2011 - March 2012: Processing, Drying, Hulling and Roasting

March - July 2012: Exporting the Coffees

May - August 2012: Roasters and Baristas experiment with the coffees

September 2012: Analyzing and Documenting

October 2012: Publishing Results

Operations within Experimentation

1. All coffees used in the experiment will be El Salvadoran coffees. 

2. The experiment will analyze two different classifications, or qualities of coffees. 

HG Coffees will be harvested and processed from November to December. They will be picked on the same day, and selected from the same area of the plantation. 

SHG Coffees will be harvested and processed from December to February. They will be picked on the same day, and selected from the same area of the plantation. 

3. Following harvesting, coffees will be divided and processed as four distinct batches. 

4. All coffees will be processed by the Mechanically Washed processing method, using the Pinhalense Mill Machinery at Beneficio El Manzano, in Santa Ana, El Salvador. 

5. Following processing at the wet mill, coffees will be marked and tagged for each specific drying method. 

A. Traditional Patio Drying 

B. Traditional Bed/Table Drying 

C. Vertical Mechanical Dryer 

D. Horizontal Mechanical Dryer

6. All coffees will be put through a resting period of one month, in warehouses at Beneficio El Manzano. 

7. All coffees will be hulled, sorted and cleaned using Pinhalense machinery at Beneficio El Manzano.

8. Coffees prepared for experimentation and analyzation and will be medium roasted, using the Diedrich IR-1 at Beneficio El Manzano’s Lab. 

9. The final step of experimentation will be a side by side cupping of all four individual coffees, first within the Mill Laboratory, followed by the specialty coffee community.

10. Experimentation will be concluded with the documentation and publication of all findings.