Coffee Bean Varieties, Roast Levels, and How Coffee Grows

Coffee lovers often wonder: where does the coffee in their cup actually come from? The journey begins not at the café, but on a tree—years before roasting or brewing ever happen. To understand your daily brew, you have to start at the source: the coffee plant.

To go from coffee tree to espresso shot involves flowering, fruit development, harvesting, processing, roasting, and brewing. Every decision at each stage—from how cherries are picked to how beans are roasted—affects the final flavor in your cup. This guide walks through each step with specific numbers and techniques used in specialty coffee production.

What Is a Coffee Tree?

Coffee comes from the Coffea plant, a woody perennial shrub or small tree in the Rubiaceae (madder) family. It’s grown as a high-value, fast-growing crop with strong global demand. In the wild, coffee trees can grow 5 to 10 meters tall, but on commercial farms they’re pruned to under 2 meters to boost yield and make harvesting easier.

How Coffee Cherries Develop

A coffee tree typically flowers for the first time around year three. The blooms are small, white, five-petaled, tubular flowers with a light jasmine scent, clustered tightly along branches. These flowers last just two or three days before falling off. Several months later, the plant produces coffee cherries—its fruit.

The coffee fruit, known as the coffee cherry, is a drupe about 1.5 cm in diameter. It starts green, then turns yellow, and ripens to a bright red—much like a cherry—hence the name. Each cherry usually contains two coffee beans, though occasionally just one. The beans sit facing each other inside the fruit, each with a flat side touching.

Each bean is encased in a thin, papery layer called the silverskin, which lies beneath a yellowish inner skin called the parchment. The beans sit in a sweet, sticky, mucilage-covered pulp. The entire fruit has an outer skin as well. All of these layers must be removed to get to the green coffee bean inside.

Harvesting Coffee Cherries

There are two main ways to harvest coffee cherries: mechanical and manual. Mechanical harvesting, widely used in Brazil, works best on large, flat farms. It’s fast and low-cost, but results in uneven ripeness and lower overall quality. Specialty coffee producers almost always handpick cherries instead, selecting only fully ripe ones. This ensures uniform size, ripeness, and purity—key factors for quality processing.

From Cherry to Green Bean: Processing Methods

Once picked, the coffee fruit must be processed to extract the beans. There are two primary methods: dry (natural) and wet (washed).

Dry Processing (Natural)

In dry processing, cherries are spread out in the sun and left to dry naturally with ventilation. Once fully dried, the outer fruit layers, including pulp and parchment, are removed mechanically. It’s the oldest, simplest, and most economical method, often used in Africa and parts of Asia. While it preserves certain aromatic compounds, it may also retain environmental odors. Some regions now use mechanical dryers to improve consistency.

Wet Processing (Washed)

Wet processing, or the washed method, starts by sorting and soaking cherries. The fruit is then fermented and pulped to remove the skin, pulp, and mucilage. What remains is the bean surrounded by a protective parchment layer. At this stage, the beans are called “parchment coffee” and are stored this way until just before export. Right before shipping, a hulling machine removes the dried parchment. This method yields cleaner, brighter flavors but requires significant water and more complex equipment—common for high-end beans.

Green Coffee to Roasted Coffee: The Roasting Process

Roasting transforms raw green coffee beans into the aromatic, flavorful beans we brew. During roasting, starches convert to sugars, acids develop, moisture and CO₂ escape, proteins break down, and fats migrate to the surface forming a coffee’s oily layer. The beans expand, develop internal pores, and take on their final color and flavor profile. It’s a technically demanding process that requires precision equipment and skill—best left to professional roasters.

The roast level directly shapes the taste: lighter roasts emphasize acidity and origin character, while darker roasts enhance bitterness, body, and Maillard reaction-driven flavors. The longer and hotter the roast, the darker the bean becomes.

Common Roast Levels (from Lightest to Darkest):

• Light Roast: Slightly yellowish-brown; mild aroma and flavor.
• Cinnamon Roast: Light brown (cinnamon color); slightly improved aroma, common in basic American-style coffee.
• Medium Roast: Medium brown (chestnut); balanced, mellow acidity—classic for standard American coffee.
• High Roast: Slightly stronger than medium; balanced acidity and bitterness, good flavor complexity.
• City Roast: Named after New York City; standard roast level, ideal for Colombian and classic New York-style coffee.
• Full City Roast: No acidity, stronger bitterness; great for iced coffee.
• French Roast: Dark, oily surface; intense bitterness and distinct smoky aroma.
• Italian Roast: Very dark, nearly black; burnt tone, minimal aroma, used for espresso.

Different beans and brewing methods may call for different roast levels. For instance, light roasts highlight unique origin traits, while dark roasts are common in espresso blends.

Types of Coffee Drinks

Beyond the roast, the way coffee is brewed and flavored leads to a wide variety of drinks. Common styles include:

• Black Coffee: Coffee brewed without milk or sugar; does not include instant coffee.
• White Coffee: A Malaysian drink made with butter-roasted beans and sweetened condensed milk—functionally a sweetened latte. In the U.S., it can also refer to lightly roasted beans brewed strong and acidic via espresso.
• Flavored Coffee: Coffee with added flavorings such as chocolate, syrups, fruit, spices like cinnamon or nutmeg, or orange blossom.
• Espresso: Concentrated coffee brewed by forcing hot water through finely-ground coffee under high pressure.
• Cappuccino: Equal parts espresso, steamed milk, and foam. Can include spices or chocolate. A double shot version is also common.
• Latte: One espresso with two or more parts steamed milk; optionally made with two shots.
• Macchiato: Espresso “stained” with a small amount of foamed milk.
• Mocha: Espresso with chocolate, milk, and cream—sometimes served over ice.
• Americano: Espresso diluted with hot water for a smoother, milder drink.
• Irish Coffee: Coffee with whiskey and topped with whipped cream.
• Viennese Coffee: Coffee with chocolate syrup, whipped cream, and colored sprinkles.
• Vietnamese Coffee: Drip-brewed through a metal filter, often sweetened with condensed milk. Served hot or cold.

Frequently Asked Questions

What is the difference between a coffee tree and a coffee plant?

A coffee tree refers to a mature, larger specimen that can reach up to 10 meters in the wild, though cultivated coffee is pruned to under 2 meters for easier harvest and higher yields. Both terms refer to the same species in the Rubiaceae family, but “tree” implies a less-managed, larger growth form.

How are coffee cherries turned into green coffee beans?

Coffee cherries are processed either by the dry method (sun-drying then hulling) or the wet method (fermentation and washing to remove pulp and mucilage). Both result in green coffee beans, which are then roasted. Dry processing is traditional and low-cost, while wet processing yields cleaner flavors but requires more water and equipment.

What are the main coffee roast levels?

Roast levels range from Light (pale brown, high acidity) to Italian (very dark, bitter, minimal aroma). Key roast types include Cinnamon, Medium, City, French, and Italian. The roast determines the balance of acidity, bitterness, and aroma in the final cup.

How does coffee harvesting affect quality?

Handpicked coffee generally results in better quality due to selective harvesting of ripe cherries. Mechanical harvesting is faster but gathers underripe and overripe fruit together, lowering cup consistency. Most specialty coffee is handpicked.

What’s the difference between wet and dry coffee processing?

Wet processing (washed) removes the coffee bean’s pulp and mucilage through fermentation and washing, yielding cleaner, brighter flavors. Dry processing (natural) dries the whole cherry in the sun and removes the dried husk later, often resulting in fruitier, earthier profiles. Wet processing uses more water and equipment, while dry processing is simpler and more traditional.

FrontStreet Coffee Beans for Roast & Variety Exploration

Explore coffee origins and roast profiles with FrontStreet’s Ethiopia Humbera, a bright Ethiopian single origin with floral and citrus notes; the washed Yirgacheffe offering juicy acidity; and the Brazil Queen Manor, a nutty, chocolatey medium roast perfect for comparing light and dark profiles. These beans showcase the impact of origin and roast degree. Freshly roasted within 5 days · Orders placed before 17:00 ship the same day · Next-day delivery across most of Guangdong Province.