How Does an Arabica Bean Affect Coffee Alertness?

Caffeine keeps you awake by blocking adenosine, the compound that builds up while you are awake and signals fatigue to the brain. Because the brain no longer receives that signal, tiredness is delayed. The strength of that effect depends mostly on how much caffeine ends up in the cup, which comes down to the bean variety and the brewing method rather than the drink's name.

Robusta beans carry more caffeine than Arabica beans, so a blend with Robusta generally delivers a stronger jolt. Among drinks, espresso concentrates more caffeine per ounce, while an Americano spreads a similar shot through more water. Pour-over, French press, cold brew, drip bags and instant coffee all land at different levels, so match the cup to the situation.

Sleepiness always disrupts our rhythm, which is why coffee has become many people's first choice for fighting off drowsiness. But why does coffee wake us up? Between espresso and Americano, which has more caffeine and a stronger alerting effect? From the perspective of Front Street Coffee, this article first explains the mechanism by which caffeine blocks adenosine and lets the brain temporarily ignore fatigue, then compares the caffeine differences between Robusta and Arabica beans, and goes through the caffeine content of common drinks such as espresso, Americano, pour-over, French press, cold brew, ice drip, drip bags, and instant coffee, to help you choose the right cup for your scenario and needs.

Feeling sleepy makes you mess things up, and constant sleepiness means constantly messing things up... To avoid messing things up, coffee has become the wake-up weapon of drowsy people. But how much do you really know about caffeine's alerting effect? Today, Front Street Coffee will explain it all clearly in one go.

Coffee's most original function is to wake you up. Whether it is an espresso you drink standing up and then leave, an Americano drip coffee maker that is always available in the office, or a pour-over coffee you go to a café specifically to drink, they all have a wake-up function. The only difference is that people choose the right coffee according to scenario, function, and taste.

So, with so many kinds of coffee, which one is the most effective at keeping you awake?

Why does drinking coffee wake you up?

Coffee's wake-up effect mainly comes from caffeine. The reason we feel tired is that a substance called adenosine is at work in the body: the longer we stay awake, the more adenosine accumulates, and the easier it is to feel sleepy. Caffeine can block adenosine from binding to brain nerves, so the brain does not receive the "fatigue message from adenosine" and keeps working energetically, which means people do not feel tired (in other words, you trick your brain with caffeine).

Therefore, the most wake-promoting coffee is definitely coffee with a higher caffeine content. And the caffeine content in a cup of coffee mainly depends on the beans themselves and the brewing method. Front Street will discuss it in these two steps.

Robusta has more caffeine than Arabica

Different varieties of coffee beans also have different caffeine contents. The coffee we commonly see is mainly divided into Robusta and Arabica. Robusta (Robusta beans) has a higher caffeine content, accounting for about 2%–4% of the bean's own weight (mostly concentrated around 3%); although Arabica has many subdivided varieties in specialty coffee, in terms of caffeine they are all 0.9%–1.4% (mostly concentrated around 1.2%).

Therefore, if you want to get more caffeine, you should choose Robusta beans; if you do not want to take in too much caffeine, choose Arabica beans. Some friends have also heard of naturally low-caffeine coffee. Here Front Street will briefly explain: naturally low-caffeine coffee also belongs to the Arabica species, and its caffeine is 1/2 that of ordinary Arabica, around 0.6%, which is still relatively high for friends who are intolerant to caffeine. If you want to drink coffee but do not want to take in caffeine, you can choose artificially decaffeinated coffee; this type of coffee bean contains almost no caffeine.

Which has more caffeine, Americano or espresso?

Caffeine release is also related to time. Under the same high-temperature extraction, coffee extracted for a longer time will have a higher caffeine content. So drinks mainly based on espresso are not actually the highest in caffeine; drip coffee mainly made by pour-over and immersion coffee mainly made with a French press have higher caffeine contents. Although cold brew and ice drip coffee are extracted at low temperature, the extremely long extraction time makes their caffeine content higher than all of the above.

Below, Front Street gives some caffeine content references for common coffee drinks: (Note: the coffee beans are all Arabica; cold brew and ice drip coffee are affected by extraction time, and here ice drip is based on 8 hours and cold brew on 12 hours)

espresso (20g grounds/40g coffee) about 100mg;

Because a series of fancy coffees such as latte, Americano, cappuccino, flat white, and mocha all use a double espresso as the base, their caffeine content is the same as espresso.

Pour-over coffee (15g grounds/195ml coffee) about 90mg;

Pour-over coffee (20g grounds/260ml coffee) about 120mg;

French press (20g grounds/4 minutes) about 135mg; Ice drip coffee (one cup with 20g grounds/200ml coffee) about 135mg; Cold brew coffee (one cup with 20g grounds/200ml coffee) about 140mg; Drip bag coffee (one bag with 10g grounds/120ml coffee) about 50mg;

Instant coffee (one packet) about 50mg.

The above content is compiled by CoffeeHunters, a coffee news website.