Coffee Bean Types

The two species of coffee beans most widely cultivated commercially are Coffea arabica (Arabica) and Coffea canephora (Robusta).

The coffee that most are accustomed to is made from arabica beans which typically have better flavor. Arabica comprises about 75-80% of world production.

Estimates of caffeine content average about 1% for Arabica beans and 2% for Robusta beans by weight.

Starbucks advertises that it only uses arabica beans, Even though its coffee consistently is rated with higher caffeine than Dunkin Donuts, McDonalds, etc.

There are a number of techniques in brewing coffee: concentrate brewing, Turkish or Greek, vacuum brewing, percolating, the French press (also called press pot or plunger coffee), and drip or filter coffee. Assuming that the brewing method stays the same, the finer you grind coffee, the more caffeine it will release.

Temperature is also an important factor. Proper coffee extraction happens between 195-205 degrees, however most drip brewers only reach about 190 degrees. Espresso machines usually brew at near boiling temps. With French press coffee, you have total control over the temperature with the option of pouring boiling water (212 degrees) over the grounds. Water temperature can vary by brewing method, with the hotter the water, the better the extraction. With better extraction comes better tasting coffee and caffeine extraction.

Brewed coffee requires that the water is in contact with the grinds for a long time, this leads to a higher caffeine concentration. Espresso actually has the lowest caffeine content at 100 mg per 2 ounces. However, if you consider the amount of caffeine per ounce, espresso has more caffeine than drip coffee. Coffee brewed in the French press has 107.5 mg per 7 ounces. Drip brewed coffee is highest, with 145 mg of caffeine per 7 ounce cup. Generally, for brewed coffee, two tablespoons of ground coffee is used per 6 fluid ounces of water.

Light, medium, and dark flavors are an indicator of flavor strength, with the dark roasts having the boldest tastes. The darker the beans, the longer they have been roasted. The loss of caffeine from light to dark is minimal, regardless of what many web sites show.

Factors, in addition to brewing process that affects the amount of caffeine: variety of coffee bean, roast level, temperature of water, amount of coffee, brew time, grind level, and beverage size.

Bottom line - longer brewing time, fine ground, robusta equals more caffeine.
Shorter brewing time, course ground, arabica, (light, medium, or dark roast) equals less caffeine.

Coffee Beans, Light vs. Dark Roast

Caffeine is extremely stable during the roasting process. A change in caffeine depends on how you measure your coffee.
There is an estimated ninety bean difference between a pound of dark and light roast coffee, with the dark roast higher. During the roasting process, a bean loses its mass. The density of the bean changes; beans that are roasted longer are less dense. That is why you have more beans by mass of dark roasts.

If you measure your coffee by scoops, light roasted coffee will have more caffeine, since the beans are denser than a darker roast. However, if you weigh your scoops, darker roasts will have more caffeine, because there is less mass. Depending on how ground coffee is measured, there is only a minimal variance in caffeine content with dark and light roasts. Unlike Marijuana,  people have died from caffeine overdose.

Guarana

This is a climbing plant in the maple family, native to the Amazon basin and especially common in Brazil. Guarana features large leaves and clusters of flowers, and is best known for its fruit, which is about the size of a coffee bean. As a dietary supplement, guarana is an effective stimulant and its seeds contain about twice the concentration of caffeine found in coffee beans (about 2–4.5% caffeine in guarana seeds compared to 1–2% for coffee beans). As with other plants producing caffeine, the high concentration of caffeine is a defensive toxin that repels herbivores from the berry and its seeds.

If you look at the contents of any energy drink, chances are that guarana is listed as one of the main ingredients. European missionaries in 17th-century Brazil recorded the native people’s use of the berry, noting that it not only gave them energy, but allowed them to go for days without feeling hungry. It became a colonial trading commodity that was said to help protect the body from illness, but too much of it was known to cause insomnia.

The caffeine that is found in the guarana berry is thought to be different from the caffeine found in coffee. Guarana contains chemical components called tannins, which are thought to produce a longer-lasting effect than caffeine from other sources. For centuries, guarana berry seeds have been powdered or smoked in a long process that is done by hand. Drinking properly prepared guarana can be central to formal occasions and gatherings, where groups of people pass around a calabash bowl.

Coffee Facts

A coffee bush does not produce usable fruit for five to six years, but then can produce for thirty to forty years after that. Coffee was eaten long before it became a liquid refreshment. African tribes would mix the coffee berries with fat and create energy balls that they would eat once or twice a day, when they needed a boost of energy. Green coffee beans were ground up and mixed with fat, then made into small balls, which were eaten by travelers on long journeys. It was the first plant to be cultivated around the world.
 
The fruit, or cherry, is a reddish two-seeded berry. The two seeds are what we call coffee beans, but are actually seeds. The cherries and leaves also contain caffeine. In some countries, the berries are fermented into wine, but mostly they are used for fertilizer or cattle feed.

Coffee was the very first food to be freeze dried in 1938. Nestle invented the freeze dried coffee. It was a milestone that was unprecedented and set a new standard for how food could be packaged and sold.

Coffee is so popular and in such high demand that it is actually the second most traded commodity on earth, only behind oil.

Mocha is a city in Yemen and the island of Java in Indonesia are two places, which types of coffee are named.

Four Coffee Seed Facts

Coffee bean is not actually a bean, it is a seed.  Beans are always seeds, but seeds are not always beans.  A bean is just one kind of a seed.  Specifically, the bean is a name for seeds of the family Fabaceae, of which the coffee plant is not a member.
A coffee bean is actually the seed of the coffee plant, the pit inside of the coffee fruit.
Only one state produces coffee, Hawaii.
English chemist, George Constant Washington invented instant coffee.
Put used coffee grounds in houseplant soil to help the plants.