Coffee Science for Sleep - Caffeine Edition | Decaf: Caffeine-Free Coffee | Does Roast Level Matter? | Low-Caffeine Varieties

When it comes to the relationship between "sleep and coffee," the first concern is probably "caffeine."

Even among professionals, there are many differences in views and perceptions, making it seem like a difficult topic. Whether you are sensitive to caffeine or not, drinking coffee will always affect your body.

To achieve both quality sleep and enjoyable coffee time, let's gain proper knowledge about "coffee and caffeine"!

 

1. Decaf Coffee: Caffeine-Free

―How to Identify Delicious Decaf

There is "decaf" as a coffee bean that contains no (or little) caffeine, but do you have negative impressions such as "tastes weak" or "inferior taste"?

This is because in the process of manufacturing decaf, it is necessary to extract not only caffeine but also all other coffee components from the beans.

However, in modern coffee shops, more and more places are offering flavorful decaf that tastes just like regular coffee, even after the decaf process.

 

 

 

So, what kind of "high-quality decaf" is there?

In Japan, the following two types generally apply.

 

(A) Swiss Water Process

(B) Supercritical Carbon Dioxide Extraction

 

(A) Swiss Water Process

Decaf produced by Swiss Water Process, headquartered in Vancouver, Canada, removes caffeine using only "water" as the raw material.

This process removes 99.9% of the caffeine while preserving rich flavor and acidity.

For more details, click here.

 

 

(B) Supercritical Carbon Dioxide Extraction

This method is also used in Japan.

Coffee processed in Japan is easier to source in a fresher state.

This method creates a chemical supercritical state to remove caffeine, so no chemicals are used here either.

For more details, click here.

For a body-friendly and delicious decaf coffee, it's a good idea to choose one that uses the methods described above.

It's also great to ask a barista at a coffee shop!

 

 

2. Coffee Roast Level and Caffeine Content

―"Lighter roasts help you sleep better" is a lie!?

 

 

 

Keywords indicating roast levels include "light roast," "medium roast," and "dark roast."

This is similar to the image of steak doneness: "rare," "medium," and "well-done."

Even with the same coffee, the flavor changes depending on the roast level: a lighter roast emphasizes acidity, while a darker roast enhances richness and bitterness.

 

 

●The bitterness of coffee is not the taste of caffeine!

A common misconception is the idea that "coffee bitterness = caffeine taste."

While caffeine affects texture (mouthfeel) and body, the cause of coffee's bitterness is the scorching of the beans during roasting.

Therefore, light-roasted, refreshing coffee contains caffeine just like bitter coffee.

Since caffeine content does not change with roast level, the idea that "light roasts help you sleep better when drunk at night" is incorrect.

 

 

 

3. Coffee Varietals and Caffeine Content

―Arabica and Robusta

 

 

Just as wine has varietals like "Chardonnay" and "Pinot Noir," coffee also has various varietals.

The caffeine content naturally varies depending on the varietal, and varietals can be broadly divided into two types: "Arabica" and "Robusta."

 

 

●Arabica Variety

Often sold as high-quality "specialty coffee" beans, these generally have a better flavor than Robusta.

 

 

●Robusta Variety

Generally inexpensive and full-bodied. Due to its strong flavor, it is often favored by Italian bar-style establishments.

Compared to Arabica, it has about twice the caffeine content.

 

 

【Attention!】Laurina variety with low caffeine

A recently noticed lineage of Arabica is the Laurina (Laureena) variety. This variety naturally has about half the caffeine content of regular Arabica.

In fact, the Laurina variety was used by the Hand Drip World Champion in 2018, and it has an exceptionally good taste despite its low caffeine content. It is occasionally sold in Japan, so please give it a try.

 

 

 

Summary - Enjoy coffee time even before bed!

Taught by Barista Naoki Yasuda

How to Brew Delicious Coffee (Beginner's Edition)

 

 

Q. Recommended water temperature?

 

Light to Medium Roast → 90℃ or higher

Dark Roast → 80℃

 

The higher the water temperature, the stronger the extraction power, so for dark roasts with stronger bitterness, extracting at a relatively lower temperature will result in a milder flavor.

 

 

Q. What grind size should I use?

Drip coffee → Start with a medium grind!

The finer the grind, the easier it is to extract flavor. If it's "too strong," try a "coarse grind"; if it's "too weak," try a "fine grind" to get it just right.

 

Q. How much coffee and water should I use?

If you're making one cup, try 15g of beans to 250g of water!

If you need two cups, simply use double the amount.

 

 

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This time's recommended music

Coffee Music -Relax Chill Jazz-

 

"Coffee Music -Relax Chill Jazz-" is a JAZZ BGM work by "JAZZ PARADISE," a representative artist who leads Japan's cafe music scene with stylish cafe and bossa nova.

Please relax your mind with pleasant music and enjoy a peaceful moment of healing.

 

 

 

 

Naoki Yasuda

Barista, Roaster

Video Director

【Career】
Born in Taito Ward, Tokyo. Studied filmmaking at RMIT University in Australia, where the director of the movie "SAW" graduated. Became engrossed in barista work, which he started as a part-time job during his studies, and pursued a career in coffee after graduation. After returning to Japan, he joined the company that organizes the Tokyo Coffee Festival, engaging in barista work, event organization, and new store launches. He then moved to La Cabra Coffee in Denmark, becoming the first Asian barista to work at their main store, and was involved in launching their Dubai store.

Became independent in 2020.

Planned and designed rebon kaisaiyu, a renovated 150-year-old abandoned public bathhouse in Taito Ward, Tokyo, into a roasting facility and coffee shop. Supervised all menu items, including a marriage set of coffee and homemade ice cream, and staff training. Featured in numerous media outlets such as OZ Magazine, Zip, and the Yomiuri Shimbun. Also involved in creating photos for the web and event planning. Since 2021, he has been producing comprehensive content for stores and brands, including design, commercial production, public relations, event planning, and live streaming.

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Profile HP: naoki.post.pro

Video Portfolio: https://vimeo.com/naokinathan