1. Legends and the Earliest Reliable Records of Coffee
A famous story about the beginning of coffee involves Kaldi, a shepherd boy in Ethiopia. According to the story, Kaldi saw his goats eating red berries and jumping with excitement, so he told a monk about it. In Japan, industry chronologies list this as an "origin legend" with an unknown date [1]. The first book to mention this tale appeared in 1671 [2].
Reliable records point to 15th-century Yemen. Within the range of verifiable books, drinking coffee became a habit among Sufi Muslim practitioners in the 15th century. By the end of that century, it seemed well-established [3]. Around 1454, a jurist in Aden is said to have been the first to drink it [3]. Japanese Wikipedia notes that a 9th-century medical text describes beans and a boiled liquid, but this may not be the same drink we know today [2]. We do not know exactly who started it, but the drink that began in 15th-century Yemen spread worldwide. How did it travel?
2. How Coffee Spread from Yemen to the World and to Japan
Coffee was not always welcomed. In 1511, it was banned in Mecca because it was considered too stimulating. In 1532, Cairo also banned it, and warehouses were damaged. However, in 1524, the highest-ranking jurist serving the Ottoman Sultan ruled that it was permissible to drink [3]. Whether coffee fit Islamic teachings was a subject of debate.
In 1517, the Ottoman Empire conquered Egypt, and coffee reached Istanbul. In 1554, the world’s first coffeehouse reportedly opened in Istanbul. It reached Venice in 1615 [1]. The first coffeehouse on mainland Europe reportedly opened in Venice in 1645 [3]. The Netherlands obtained seedlings in 1616 and began cultivation in Java in 1658. In 1720, a French person reportedly carried seedlings to Martinique, and seeds arrived in Brazil in 1727 [3].
In Japan, coffee is said to have arrived during the Edo period through Dejima in Nagasaki. Sources disagree on the timing: some say after 1641 [1], while others say the 18th century [2]. The first full-scale coffee shop in Japan opened in Ueno, Tokyo, in 1888 [2]. Records of "iced coffee" cooled with ice exist in Tokyo in 1891 [4]. Coffee became popular among ordinary people around the end of the Meiji era and the beginning of the Taisho era [2].
Coffee is naturally bitter. Yet it has been consumed globally. Children often dislike bitter things. Why do adults learn to like it?
3. Why People Learn to Like Coffee's Bitter Taste
Children tend to dislike bitter tastes more than adults do [5]. The bitterness in coffee comes not just from caffeine, but from other bitter compounds as well. Caffeine accounts for only part of the bitterness [5].
One possible explanation for why people come to like coffee is "learning." The idea is that by drinking it repeatedly, the brain connects the bitter taste with the effects of caffeine, eventually finding it pleasant [5].
Genetics also play a role. A 2018 study of data from about 440,000 people in the UK reported that those genetically predisposed to perceive caffeine’s bitterness more strongly tended to drink more coffee. However, the difference was small, about 0.02 to 0.15 cups per day. The study was limited to people of European descent in the UK [6].
In summary, we do not fully understand why people like coffee. We know children tend to dislike bitterness, there are individual differences in sensitivity, and preferences can change through repetition. You can also change the bitterness and strength by how you brew it, such as adding hot water, milk, or cooling it. Let us look at common ways to drink it.
4. Common Ways to Drink Coffee: Hot, Iced, Espresso, and More
Hot: This is warm coffee made by pouring hot water through ground beans. Differences in extraction are discussed in Section 7.
Iced: In Japan, drinking cooled coffee began in the Meiji era. It became common in coffee shops in the mid-1950s and spread widely after the 1970s [4].
Espresso: This is a concentrated coffee made by forcing hot water through grounds at about 9 to 10 atmospheres of pressure. One cup uses about 7g of beans and extracts about 30cc. It uses deeply roasted, finely ground beans. It originated in Italy; a machine was built in 1901, and it was shown at the Milan World’s Fair in 1906 [7].
Americano: This is espresso diluted with hot water [8].
Cafe Latte: This mixes espresso and milk. In Italian, it means "coffee-milk" [9].
In Japan, "American" refers to coffee brewed with lightly roasted beans or coffee with low concentration, which is different from an Americano. The origin of the name has several theories and is unclear [8].
All these drinks start with the seeds of the coffee cherry. The type of bean and its origin also change the taste.
5. Coffee Bean Types and Where They Come From
Two main types of beans are sold commercially. Arabica beans originate in the highlands of Ethiopia and prefer cool temperatures of about 18 to 21 degrees Celsius. Canephora beans originate near the equator in Congo and grow in lower altitudes [13].
Robusta is a variety within Canephora. Because most Canephora beans were Robusta, the name became widespread [10][14]. Canephora is described as having less acidity and stronger bitterness, with less rich aroma and flavor compared to Arabica. However, it has nearly twice the caffeine, is resistant to coffee leaf rust, and yields up to about 3 times more beans per area [13].
Brazil is the largest producer, accounting for nearly 40% of world production [15]. Brazil’s forecast for 2026/27 is about 72 million bags. Vietnam is estimated at about 32 million bags for 2025/26, second only to Brazil, followed by Colombia [15]. For Canephora alone, Vietnam is first with 37%, Brazil second with 28%, Indonesia third with 12%, and Uganda fourth with 7% [13].
Vietnam is the largest producer of Canephora. Over 90% of its production is Canephora, and about 80% is grown in the central highlands. Da Lat, at about 1,500m elevation, is a main area for Arabica [11]. The French began cultivating coffee in northern Vietnam around 1850 (some sources say 1857), initially with Arabica. In the 1980s, the government led cultivation efforts [11].
Vietnamese coffee has unique characteristics. The mainstream style is strong coffee brewed with a "phin" filter, mixed with sweetened condensed milk [12]. It is explained that because Canephora is very bitter and hard to drink black, and milk was hard to get, condensed milk was added instead [12]. There is also egg coffee, where whipped egg yolk and condensed milk float on top. This connects to Section 3: it is a way to enjoy bitter beans by making them sweet.
6. How Roasting Changes the Taste of Coffee
Green coffee beans have little taste or aroma. Roasting brings out acidity, bitterness, sweetness, and aroma. Coffee’s unique scent is created during roasting. Freshly roasted beans have the most aroma compounds, which fade over time [16].
Roasters are classified by how they transfer heat: direct fire, semi-hot air, and hot air. Direct fire transfers burner heat directly to beans. Hot air sends heated air from a burner into the drum. Descriptions of semi-hot air vary: some say it uses heat from a heated drum and hot air from behind [17], while others say it heats a drum with no holes directly with a burner [18].
Roast levels are generally divided into 8 stages, from light to dark: Light, Cinnamon, Medium, High, City, Full City, French, and Italian. Broadly, they are light, medium, and dark roasts. Light roast is a yellowish wheat color; Italian roast is nearly black [16].
Lighter roasts tend to be more acidic, while darker roasts taste more bitter [16]. Espresso uses dark-roasted, fine grounds [7].
7. Coffee Brewing Methods: Drip, Siphon, and French Press
Brewing methods are mainly divided into "percolation" (pouring water through grounds, like paper or cloth drip) and "immersion" (soaking grounds in water, like French press). Some paper drips have elements of immersion [19].
Paper Drip: Simple tools and a clean taste, but flavor can vary with pouring technique.
Cloth Drip: Uses a cloth filter. The loose weave lets oils through, resulting in a smooth, rich taste.
Siphon: Heats water in a glass bulb, pushing it up to mix with grounds. High temperature releases aroma.
French Press: Steeps grounds in water for a while. Long contact time brings out the full bean flavor.
AeroPress: Uses pressure. The device itself does not use fire or electricity, but extracts coffee under pressure.
These taste descriptions come from a coffee company’s own guide [19]. Read them as rough guides, as skill and preference vary.
Paper filters were invented in 1908 by Melitta Bentz in Dresden, Germany. She reportedly used blotting paper torn from her son’s homework notebook in a brass cup with holes. Before this, grounds often ended up in the cup, leaving an unpleasant aftertaste. At the 1909 Leipzig Fair, over 1,200 units were sold [20].
8. How to Check the Coffee Facts Yourself
You can verify the content of this notebook with everyday items and public resources.
What you can do today: Look at coffee bean packaging. It may list origin, roast level, and variety. Try to find where it falls in the 8 roast stages [16]. Compare paper drip tools and French presses. Think about whether they pour water through or soak the grounds [19].
Note-taking tip: Write down one word that interests you, such as "Canephora" or "immersion." It will be a good starting point for further research.