Coffee: Balancing the Complexity of Production and Providing Caffeine
A cup of coffee is a revered part of many people’s morning rituals. Whether it’s a cup with friends or work day savior, over 2 billion cups of coffee are consumed daily and the global coffee market was valued at a staggering USD 465.9 billion in the year 2020!
Since October 1 marks International Coffee Day, we wanted to share some background on the process of coffee production, where coffee is produced in the world and the unexpected but important role of agronomics in coffee quality and production.
Understanding the Coffee Production Process
While a delicious cup of joe might magically appear out of a coffee pot each morning, there’s an interesting backstory on the beans and how they make it into our cups. There’s a ten-step process from plant to bean to brew.
- Planting: Coffea trees are shrub-like plants that were domesticated in Ethiopia. They grow from a coffee bean – an unroasted one, of course! Coffee plant cultivation involves planting in beds, protecting seedlings from direct sunlight, and watering frequently.
- Harvesting: Coffee trees can take three to four years to bear fruit. Called coffee cherries, the fruit of coffee trees are bright red when ripe and often require hand-picking due to ripening time variability. In some places, particularly where the plantations are flat and large, harvesting has been mechanized. Cherries can either be picked by stripping all the fruit off an entire branch at once, or individually based on their ripeness. Typically, there is one main harvest of coffee cherries per year.
- Processing: Cherries are processed quickly after harvesting to avoid spoilage. Processing can be done using a dry method or a wet method, depending on local resources. The dry method involves spreading freshly picked cherries on large surfaces to dry in the sun and raking them throughout the day.
The wet method removes the coffee cherry pulp to dry the cherries with only the parchment skin. The cherries travel through a pulping machine to separate the skin from the pulp, and then the beans are separated by weight as they sink or float in water channels. Heavy, flavorful fruits will sink. After being separated by rotating drums, the beans are fermented in water.
- Drying: After 12 to 48 hours, wet method processed beans must be rinsed and dried. Beans are sun-dried or machine-dried in large tumblers until they reach 11% moisture.
- Milling: The milling of coffee cherries is a multi-step, pre-export process. Wet or dry processed coffee is hulled to remove the parchment layer or the entire dried husk from the cherries. Polishing may be done to remove any remaining silver skin. Then, beans are sorted and graded by size, weight, color flaws, and imperfections. Beans can be sorted using air jets to separate beans by weight. Defective beans are removed.
- Exporting: The beans are ready for international travel. They’re loaded onto ships in shipping or plastic-lined containers.
- Tasting: Coffee tasting, or “cupping”, is done by professionals looking for bean visual quality, aroma, and taste. Beans are roasted in a small roaster, then ground and infused for the copper to smell and taste. Coffees are evaluated for the purpose of blending different beans or building the right roast.
- Roasting: Beans are roasted to convert them from green coffee into aromatic beans that are ground and used to make that cup of joe. Beans are roasted at about 550 degrees Fahrenheit. Once the beans reach 400 degrees, the oil inside the beans begins to emerge and creates the well-known coffee flavor and aroma. Beans are cooled by air or water. Once roasted, beans are on the clock for reaching the consumer. Once roasted, beans are on the clock for reaching the consumer.
- Grinding: Beans are then ground to the appropriate coarseness for the intended brewing method. The finer the grind, the more quickly coffee should be prepared.
- Brewing: The last step in the coffee process is extracting the coffee through brewing. Coffee can be brewed in many different ways, depending on the grind and drinker’s preference. For example, espresso machines use fine coffee and high pressure to extract coffee and make the perfect latte or macchiato!
Coffee Around the World
Coffee has as diverse growing locations as it does drinking locations. Over 50 countries around the world produce coffee, though the ideal location for coffee cultivation is along the Equatorial zone, between latitudes 25 degrees North and 30 degrees South. This area is referred to as “The Bean Belt”. Different varieties of coffee thrive at different altitudes, in different soils, and at different temperatures.
Guatemala, Costa Rica, Columbia, Brazil, Ethiopia, Kenya, the Ivory Coast, Yemen, Indonesia, Hawaii, Mexico, Puerto Rice, and Vietnam all have notable coffee production. Coffee from different areas produces different flavors and aromas.
Hawaiian coffee takes advantage of good rains, black volcanic soils, and tropical clouds to provide a rich, aromatic, medium-bodied coffee. In Puerto Rico, two major growing regions produce coffee with a balanced body and acidity and a fruity aroma. Indonesia is known for fine-aged coffees with a deeper body and less acidity. Vietnamese coffee plant cultivation happens on small plantations but the country is quickly becoming a major coffee production powerhouse. Much Vietnamese coffee is used for blending due to its mild body and light acidity.
The quality and flavor of coffee are dependent on many variables. Plant variety and genetics, soil, climate, rainfall, sunlight or shade, altitude, and nutrient inputs all change the characteristics of coffee. For example, Guatemalan coffee grown at altitudes of 4500 feet is described as “strictly hard beans” and has a unique spicy or chocolatey complexity. Yemeni coffee cultivation happens in areas where water is sparse and the beans tend to be small and irregularly shaped, with a deep, rich, distinctive flavor.
The Agronomics Behind the “Cup of Joe”
Coffee plant cultivation requires agronomic expertise. Soil, rainfall, shade, and wind all answer the question of what affects coffee production.
Soil requirements for growing coffee include deep, well-drained soils. Oftentimes, volcanic-origin soils are good for growing coffee. Leached topsoil, poor drainage, or solid rock near the surface of the soil will not meet the coffee trees’ requirements for growing.
Coffee will perform well in soils that handle high rainfall by distributing the moisture in the soil. However, fertilizer leaching is a risk in these areas, requiring intentional management for coffee plant cultivation sustainability.
Rainfall distribution is important for coffee production. Too much moisture can increase vegetative growth and reduce fruiting, while a short dry period can help synchronize the cropping cycle. Plantations can irrigate to manage the moisture needs of the coffee plant.
Shade can be used intentionally by coffee growers to address climates that are too warm for coffee. Restricting light can also prevent trees from overbearing in areas where fertilizer supplies are limited.
Coffee trees are susceptible to wind and require a windbreak to prevent tearing, cupping, and removal of leaves or even ripe cherries.
What affects coffee production?
Outside of Mother Nature, coffee characteristics can be heavily influenced by cultivation practices. Coffee plantations will take fertilizer and irrigation requirements into consideration as well as pesticide application needs.
The first five years of a coffee plant’s life are the most critical. During this time, coffee plant nutrition needs must be met to encourage vigorous root and leaf growth. Young trees have high phosphorus requirements to promote root production.
Once trees are bearing fruit, the coffee plant nutrition needs change to sustain leaves, stems, roots, and fruit. In the plantation orchard system, pruned wood and coffee leaf litter return nutrients to the soil. But, nutrients may be lost by leaching, erosion, or volatilization. Farmers may apply fertilizer for coffee nutrient management through an irrigation system or broadcast it by hand.
Second-year and older trees can have leaf tissue analyzed to identify any nutrient imbalances. Tissue tests can identify nutrient deficiencies before they become visible symptoms. Fertilizers for coffee plants can be customized based on the results of the tissue analysis.
Irrigation is an important topic in coffee cultivation. In areas with less than 60 inches of rainfall a year, irrigation is recommended, though water needs are often referred to in terms of “crop coefficient,” or the crop’s water demand in relation to the evaporation occurring in an open pan of water in the orchard. Water needs also differ for young, nonbearing trees and two-year and older trees.
Drip or micro-emitter systems are often used on plantations. Applying water is a balance between cost efficiency and plant health. Overirrigation is a risk for coffee plant cultivation and can cause poor root development and even death. Overirrigation is more likely if there is a solid rock pan below the topsoil that catches water and allows it to stand.
Weeds, diseases, and insects can be other challenges to growing coffee. Coffee plantations can control what major weeds they experience through manual or mechanized means. The major vines of concern are morning glory, ivy gourd, and bitter melon. Weed control can cost up to 10% of annual growing costs. Groundcovers can be used preventatively for weed control.
Green scale is one of the most impactful pests for coffee as it sucks sap from the coffee plant and covers the leaves in black sooty mold that reduces photosynthesis. Green scale can be biologically controlled with white halo fungus. Growers can also use soil or foliar applied imidacloprid to control green scale.
Black twig borer is another damaging insect in coffee plant cultivation. It causes wilting and death of leaves and wood, leaving bark black. The best control for these beetles is keeping trees healthy and pruning infested laterals.
Coffee is also susceptible to nematodes and disease. Root-knot nematodes enter and feed on roots, disrupting growth. Cercospora leaf spot is a common fungus in coffee-growing areas but can be controlled by managing growing conditions and coffee plant nutrition needs.
Other funguses to which coffee is susceptible include coffee leaf rust and coffee berry disease. Coffee leaf rust causes yellow-orange lesions on the leaves, and the fungus is spread by wind, rain, or even the clothing and coffee bags around the coffee trees. Copper fungicides and resistant varieties are the main methods of control.
Coffee berry disease causes brown, sunken lesions on green cherries and eventually will destroy the bean. Quarantine is the best control for the fungus. The most aggressive strain of coffee berry disease is found in Africa, though other strains are seen worldwide.
What are the challenges of growing coffee?
In recent years, coffee production has been troubled by a variety of challenges. Around the world, June 2022 production estimates have been lowered from the December 2021 projections. Too much rainfall and cloud cover has cut back Columbian crop production, while Honduras production estimates have dropped 1.4 million bags due to leaf rust slashing yields. Brazil’s drought and cold cultivation season in 2021 caused farmers to cut down coffee trees.
With harvest 2022 in sight, Brazil’s coffee crop is projected to be at its lowest since 2014. This year’s arabica cherries have smaller than usual beans leading to disappointing yields. Smaller beans mean more are required to fill weight-based bags, and overall output is reduced.
Sustainable Production and Improved Quality with Agmatix
Coffee crop cultivation can be a challenge! Between pests, disease, climate sensitivity, and meeting plant nutrition needs, attaining high yields and good quality cherries can feel very difficult. The good news is that crop management software can help collect data and support decision-making for the most productive, most sustainable crop possible.
Agmatix is an agro informatics company dedicated to transforming data into insights. For coffee growers, the Digital Crop Advisor platform can help optimize crop nutrition management, customize fertilization planning, and monitor sustainability KPIs of nutrition plans and agronomic practices.
Our Digital Crop Advisor is a decision support system with scientifically-proven data to inform specific crop protocol management. Insights are based on over 150 crops and crop-essential nutrients, and multi-device support makes it easy to optimize crop nutrition with the planning tool.
The Digital Crop Advisor also simplifies coffee nutrient management with seamless crop nutrition optimization plans through a customized fertilization planning tool. It’s key to meet coffee plant nutrition needs, but those needs may differ based on plant age, growth stage, climate, and more. Because fertilizer for coffee plants has a risk of leaching, especially in certain soil types, precise and well-timed applications are key. Digital Crop Advisor makes balancing meeting coffee plant nutrition needs with protecting the environment easier than ever before.
Agronomic data insights are available through the analysis of aggregated and standardized data. Both legacy and ongoing research data can be visualized and analyzed to support decision-making. Agmatix also makes it easy to harness the expertise of advisors and researchers through a collaboration wizard.
Understanding the environmental impact of decision-making in coffee cultivation can be challenging. The Digital Crop Advisor allows users to monitor sustainability KPIs such as carbon footprint and nitrogen leaching. Integrated support of lab analysis is supported, and the customized fertilization planning tool helps producers understand the environmental impact of nutrient recommendations before they are used on the plantation.
While “sustainability” is a buzzword in many areas of agriculture, coffee production can have a big environmental impact, and coffee trees are particularly sensitive to changes in climate, making changes in climate of particular concern for coffee plant cultivation. Coffee quality can be negatively impacted by changing light exposure, altitude, water stress, temperature, carbon dioxide, and nutrient management. Using tools like Agmatix’s Digital Crop Advisor is a win-win for higher production, better quality, and sustainable production for the future of a good brew.