“I’m pleased.”, “I feel so good.” or “I want to try it at home.” On a TV program on NHK, the interviewees were answering such when they tried hojicha, a roasted green tea. It seems that hojicha has an ability to make people happy. Today, I want to talk about what I learned from the TV program.
It is known that there is a substance in green tea to make you relax which is called theanine, one kind of amino acid which is umami flavor. If you check the alpha wave in your brain, you can tell that you will get relaxed when you drink green tea. Green tea in a broad sense can sometimes include hojicha in its category. But in the TV program, they meant green tea in a limited sense as sencha, a most common green tea. Hojicha is the tea produced by roasting green tea.
Left: before drinking tea, Right: after drinking tea
The red part at the right bottom in the image represents the activity of alpha wave.
Alpha wave in the brain indicates relaxation.
The red part increased after drinking green tea.
How does it happen with hojicha? Surprisingly, hojicha has only 1/100 of the theanine that green tea has. Theanin (umami), catechin (bitterness) and caffeine decrease when producing hojicha out of green tea. However, you can see as much alpha-wave increase with hojicha as the one with green tea. That means that hojicha has an equivalent relaxing effect that green tea has even if theanin is at a much lower level. It is a quite interesting fact.
|Left: before drinking hojicha, Right: after drinking hojicha|
They had a test, in which they held a hojicha tasting in public. In the beginning, they could not get many people to try the tea, but once they turned on a secret device, people started gathering and made a crowd at the site. The device is a hojicha-aroma diffuser. The odor has some kind of positive effect that attracts people.
They had another alpha test with using only hojicha aroma that showed a similar result as with drinking hojicha. Hojicha can provide relaxation even without drinking it. Just the aroma from roasting green tea can bring you happiness.
People living in other countries may not be familiar with the smell of hojicha. Can you imagine the odor? For Japanese, most of us know the aroma. Many tea shops have a tea roaster and making hojicha while producing an inviting smell. In a shopping mall, you can tell there is a tea shop by the odor from a distance. I’ll talk about the fragrance of hojicha on the next post.