コーヒーの鮮度

Coffee freshness

Hello everyone, I'm going to prepare something for coffee with you today.

. . .
I missed Taiwan so much that I ended up speaking in Chinese.

Well, today is what you've all been waiting for.
Today, I will bring you some very useful knowledge!!! (I'm not sure I won't get into some obscure knowledge along the way)

Today's theme is:

What do you need to make coffee at home?

At first glance, this seems like pretty practical knowledge.

<Required Items>

Coffee beans
hot water
Dripper
filter
kettle
scale
grinder

It's full of katakana.
I'm not a big fan of writing in English, but I'll try to write it in Japanese.

Coffee beans
hot water
Coffee funnel
Coffee Filter Paper
Coffee kettle
Scale
Coffee grinder

. . .

It's kind of hard to understand... I think I'll write it in katakana after all.

I'll explain each one!

1. Coffee beans

The undisputed hero. Without him, no matter how expensive your tools are, they are meaningless.
Coffee brewing without coffee beans is like Momotaro without the peach, or lemonade without the lemons. A void.

For information on how to choose coffee beans, please take a look at this article.

We recommend using the freshest coffee beans possible.

That's what any coffee shop owner would say.
However, today I want to say, "Wait a minute."

Of course, I am particular about the freshness of the coffee beans I sell and the coffee I serve in my shop, but recently I've been feeling a little skeptical about the idea that coffee freshness = good .

Because of the effects of COVID-19, I can no longer go to Taiwan myself, and I make coffee at home using beans sent from Taiwan, but the shipping costs for international shipping are quite high, so I can't send them that often. So recently, I've resigned myself to drinking coffee that was roasted one to two months ago.

But it's still delicious .

Oh no.
I had hoped to share some practical knowledge today, but I suddenly felt like talking about the freshness of this coffee.

So, today's theme is changed.

"Who benefits? About the freshness of coffee"

Coffee freshness

Indeed, the aroma is outstanding 1-2 weeks after roasting.
I noticed that after two weeks, the aroma gradually faded when I was QC-ing the beans at the store. However, I'm not sure if this subtle difference can be noticed anywhere else but at coffee shops.

For example, if a sommelier said, "This wine has gone a little bad," I probably wouldn't notice, and if a farmer said, "This year's tomatoes are a little less sweet," I probably wouldn't notice.
Well, I can't drink alcohol and I don't like tomatoes.

However, after two weeks the aroma will gradually fade, but on the other hand, as the aroma settles down the flavor becomes milder , so in my personal opinion even unique beans that might not be to everyone's taste can now be enjoyed.

I'm currently drinking coffee that was roasted at the end of February, and it's delicious. Costa Rican red honey is really good.
(It's nothing compared to Starbucks, and to be honest there isn't much difference when compared to the coffee at specialty coffee shops in Tokyo.)

Well, if it's okay if they're old, then I can just buy beans from the supermarket! But please wait a moment.

Beans that you buy at the supermarket and beans that are roasted and managed with the assumption that they will last 1-2 years after roasting are of a different level of age to begin with (what I call ``not fresh'' is 1-2 months, while beans from the supermarket are several years), and the quality of the beans themselves is also quite different.
Regardless of whether they deteriorate or not, beans that were originally delicious will continue to taste good even after time has passed, and beans that were not delicious will continue to taste bad even after time has passed .

The ranking will never be reversed over time.

Light roast or dark roast?

By the way, in Taiwan, it is said that lightly roasted beans last longer than darkly roasted beans , and many stores sell beans that have been roasted for about a month.

To be honest, I don't know the reason.

However, light roasts retain a higher proportion of the original aroma and flavor of the coffee beans, and have a greater total amount of flavor (aroma) to begin with , so one reason for this is that they still taste delicious even if some of the flavor is lost over time .

One Danish coffee roaster says that the best time to drink it is one month after roasting , and as mentioned above, it is common in Taiwan to let lightly roasted beans rest for a long time .
By the way, in my experience, the beans that I find delicious are lightly roasted.

Conversely, some people say that dark roasts last longer.
Their claim based on their own experience is that the taste does not change over time and that stable extraction is possible . They say that the taste changes drastically with light roasts . In the first place, light flavors such as citrus flavors tend to fade easily , so light roasts, which are dominated by light flavors, tend to deteriorate more.

As an example, when Starbucks exports coffee roasted in Seattle all over the world, they have to use sea freight, so they have to use beans that will last a long time, which is why they choose a dark roast.

However, when you look at the discussion, the point of dark roasting is almost always that "deterioration = difference," and it's all about how much difference there is between immediately after roasting and after some time has passed .

On the other hand, light roasts are described in terms of whether they are delicious in absolute terms.

So, when you dark roast coffee, a large part of the coffee components and flavor are already lost, and it is already in a state close to the deterioration of light roast coffee .
In other words, if you take into account the fact that dark roasted beans have almost no potential for further deterioration , most people would agree.

While advocates of light roasting say that it tastes better even after a while ,
The dark roast advocates say that nothing will change over time .

The points are completely different.

So to sum up:
Light roasts are more susceptible to deterioration (compared to dark roasts) in the sense of "deterioration = difference," but the rate at which quality declines over time after roasting is simply greater than with dark roasts. The total amount of flavor is greater to begin with, and in fact, even after a certain amount of time has passed, there is not much noticeable change, making them perfectly delicious to drink .

Dark roasts don't seem to deteriorate, but the deterioration is less noticeable because there are no light flavors to lose in the first place .

This makes sense, considering that from a QC perspective, Starbucks places importance not just on not letting their beans deteriorate, but on ensuring that the flavor does not change immediately after roasting.



These discussions are basically based on opinions based on actual experience (it was delicious, it wasn't delicious) .
However, to dig deeper, we need to look at it from a scientific perspective (based on the chemical reactions that occur in coffee) , and frankly, we still don't know for sure how it actually works.

One Canadian roaster says that light roasts produce less carbon dioxide during the roasting process, which then escapes more slowly, resulting in slower deterioration. Others say that dark roasts release a lot of oil after roasting, which accelerates deterioration.
It's possible that light roasts have a lower rate of deterioration (not the difference but the absolute loss in quality) when coffee is scientifically analyzed, but we'll never know.

These days, scientific approaches are mainstream in the coffee industry, so I'll stop here for today and wait for scientists to numerically unravel it.

Ah, in the end, this article turned out to be quite niche.

As an apologetic gesture, I'll include a link to how to brew drip coffee .

2. About hot water

I was going to explain this too, but I gave up. I'll do it next time.

Well, have a nice weekend!

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