July 1, 2014

Coffee Roasting with My Perforated Shallow Pot, Final Post/穴あきの浅鍋によるコーヒー焙煎、最終

Edited to add on July 5: I uploaded this and other videos to YouTube.
7/5追記: YouTubeにこのビデオなどをアップしました。


Edited to add on July 27: I hope you view these videos:
7/27追記: 次の2つのビデオを見て下さい:
Coffee roasting with a perforated shallow pot, final version/穴あきの浅鍋によるコーヒー焙煎、最終版
Coffee roasting with a perforated shallow pot, Part 2/穴あきの浅鍋によるコーヒー焙煎、パート2


***
Coffee roasting is largely divided into two types, direct flame and hot air. I regard my way of roasting as the former, and I bring the pot as close to the flame as possible.

Here's a brief description of the coffee roasting procedure:

IMPORTANT: Take all the necessary measures to prevent fires.
Caution: The considerable amount of chaff that comes off the beans during roasting and during cooling is a major problem, so is the amount of smoke generated during roasting. I do the roasting in the garage. If you decided to roast coffee outdoors, make sure that the flame is not affected by wind.


Assumptions:
1. Your portable gas stove has a heating power of about 3 kW (2,600 kW/h).
2. The amount of green coffee beans to roast is 300-400 g in weight.

0. Get all the necessary equipment.
1. Remove defective beans and foreign objects.
(I rarely remove defective beans, except extremely bad ones. I do remove foreign objects such as small stones. I can easily detect defective beans after roasting, and I usually simply remove very bad ones just before grinding.)
2. Measure out the desired amount of coffee beans.
Note that green coffee beans will lose their weight when roasted by about 12 (light roast) to 20% (dark roast).
I usually aim for 14-15% by bringing the beans to the end of first crack. A weight loss of 16% or greater is dark for me.
3. Transfer the beans to the pot, and cover the pot almost entirely, not entirely, with aluminum foil to keep the atmosphere inside the pot moist in the drying phase while at the same time preventing the beans from becoming smoky and also making the beans visible. Be sure to wear leather gloves before starting to roast.
4. Start roasting: Turn on the stove to medium, press the start button of the timer, and bring the pot as close to the flame as possible. And, start shaking!
5. 2 minutes after the start of roasting: Check that no chaff starts to come off the beans (I mean, no chaff falls onto the stove through the holes). If it does, remove the pot from the stove immediately, turn down the heat to low, and start roasting again.
6. 3-4 minutes: Check that chaff starts to come off the beans.
7. 9 minutes: Check that first crack does not occur yet. If it does, remove the pot from the stove immediately, turn down the heat to low, and start roasting again.
8. 10 minutes: The drying phase is almost over.  You may:
a. Turn up the stove to high at this point, and first crack will start soon, or
b. Keep drying the beans for another 2 minutes or so, and then turn up the stove to high, and first crack will start soon.
Note: I'm still a learner myself, and I can't give you definitive advise on when to stop the drying phase and move on to the chemical reaction phase. A lot of factors come into play, especially the weight of the coffee beans. All I can say is to watch the beans carefully to make the decision. Anyway, first crack should start 10-14 minutes after the start of roasting.
I can't talk about second crack because I've never brought my beans to second crack.
EDITED TO ADD: I totally forgot to write about when to remove the aluminum foil. Remove the aluminum foil when the drying phase is over OR remove it 1-2 minutes after the start of the chemical reaction phase. Again, watch the coffee beans carefully and make the decision.
9. Just when you think that your beans have been roasted to your desired level, transfer them to a sieve, and cool them immediately.
10. Measure the weight of the roasted coffee beans, and calculate the weight loss.
***
コーヒー焙煎は大きく、直火(じかび、ちょっか)と熱風(ねっぷう)の2種類に分けられます。私は自分の焙煎方法は直火だと思っているので、鍋をできるだけ炎に近づけています。

以下は、コーヒー焙煎の手順の簡単な説明です。

重要: 火事を防ぐため必要な処置を取ってください。
注意: 焙煎中及び冷却中に豆から剥がれるチャフ、並びに焙煎中に発生する煙は、大きな問題です。私はガレージ(車庫)で焙煎をしています。屋外でコーヒー焙煎をする場合は、炎が風の影響を受けないよう注意して下さい。

仮定:
1. 携帯用のガスコンロの熱量は、3 kW (2,600 kW/h)程度。
2. 焙煎する生豆(きまめ、なままめ)の量は300~400 g。

0. 必要な機材を用意します。
1. 欠点豆と異物を取り除きます。
(私は極端に悪い豆以外は欠点豆を取ることはめったにないです。小さな石など異物は取りますが。焙煎後に欠点豆はすぐに見つけられますし、通常は単に、挽く直前に悪い豆を取り除いています。)
2. 焙煎する量の豆を測ります。
生豆は焙煎すると、12%(浅煎り)~20%(深煎り)程度、重量が減ります。
私の場合、通常は、1ハゼ(いちはぜ)まで持って行って、14~15%を狙っています。16%以上の重量減だと私には深煎りです。
3. 豆を鍋に移し、鍋をアルミホイルでほぼ完全に(完全ではなく)覆います。乾燥段階で鍋の中の雰囲気の湿度を保ち、同時に豆が煙臭くなるのを防ぎ、また豆が見えるようにするためです。焙煎を始める前に必ず皮手(かわて)を着用して下さい。
4. 焙煎開始: コンロを中火にして、タイマーのスタートボタンを押し、鍋をコンロになるべく近づけます。そして振り始めます。
5. 焙煎開始2分後: チャフが豆から剥がれ始めない(つまり、チャフが穴を通してコンロに落ち始めない)ことを確認します。もし剥がれ始めたら、すぐにコンロから鍋を下し、火を弱め、焙煎を再開します。
6. 3~4分: チャフが豆から剥がれ始めるのを確認します。
7. 9分: まだ1ハゼが起きないことを確認します。もし起きたら、 すぐにコンロから鍋を下し、火を弱め、焙煎を再開します。
8. 10分: 乾燥段階はほぼ終わりです。次のどちらかを行います:
a. この時点で火力を高にする。そうすると、1ハゼがまもなく始まります。
b. もう2分程度、豆を乾燥させ、それから火力を高にする。そうすると、1ハゼがまもなく始まります。
注: 私自身、まだ勉強中なので、いつ乾燥段階を終わらせ、化学反応段階に移行させるかについては明確な助言はできません。色んな要素(特にコーヒー豆の重さ)が絡んでいます。言えることは、豆を注意深く観察して、決断すべきだということです。とにかく、1ハゼは焙煎開始から10~14分後に始まるべきです。
2ハゼ(にはぜ)については語れません。2ハゼまで持って行ったことがないので。
追記: アルミホイルをいつ取り去るかについて書くことをすっかり忘れていました。アルミホイルは乾燥段階が終わったら外すか、または化学反応段階の始まりから1~2分後に外して下さい。繰り返しますが、豆を注意深く観察して、決断して下さい。
9. 望みのレベルまで豆が焙煎できたと思ったら、すぐにザルに移し、すぐに冷却します。
10. 焙煎した豆の重さを測り、重量減を計算します。

5 comments:

Peter Gabriel said...

Hiroyuki,

I like your innovation on home roasting coffee ...and I like your passion. I am from the UK but just like all things coffee. I have 2 questions ...

1. Why do you insist on drying coffee on low heat for 10 minutes. You insist first crack should not occur before that ? . Whats the rationale behind this step as it bewilders me ? How does it help the flavor of coffee ? I thought hitting the doors of first crack at the earliest was recommended. Smaller the roast volume, faster the roast is it not ? or am I wrong ?
2. And once first crack comes after 10-11 mts how long do you give time for roast development and 3. do you reduce the heat after first crack or do you coast through first crack with the same heat ?

I dont like dark roasts and rarely touch second crack. I like mine crisp and clean untinged by any roast flavors .

Appreciate your time Sir !

Pete

Hiroyuki said...

Peter:

>1. Why do you insist on drying coffee on low heat for 10 minutes. You insist first crack should not occur before that ? . Whats the rationale behind this step as it bewilders me ?

First of all, I'm talking about direct-flame coffee roasting, not hot air. With the hot-air method, the total roasting time should be much shorter, say, 6 minutes. By "direct flame", I mean roasting in a perforated drum (pot, in my case) with a gas burner beneath it. (I understand that true direct flame roasting is roasting in a drum with a gas burner inside.)

The 10-minute drying phase is necessary for drying each and every green coffee bean entirely.

>How does it help the flavor of coffee ?

With the direct-flame method, roasting for a shorter period of time, say 6 minutes, simply results in flavorless coffee.

>I thought hitting the doors of first crack at the earliest was recommended.

Maybe it's true for the hot-air method, but I'm not sure.

>Smaller the roast volume, faster the roast is it not ?

No matter how small the volume may be, the roasting time should be the same, I suppose.

>2. And once first crack comes after 10-11 mts how long do you give time for roast development

That depends. Usually 3-4 minutes, until the end of first crack.

>and 3. do you reduce the heat after first crack or do you coast through first crack with the same heat ?

I don't reduce the heat while first crack is in progress. Like I mentioned in the video, I have never brought my beans to second crack, but if I were to bring them to second crack, I would reduce the heat when second crack occurs.

>I dont like dark roasts and rarely touch second crack. I like mine crisp and clean untinged by any roast flavors .

Me, either! I like medium roasts. I like to have a good balance of acidity and bitterness!

Peter Gabriel said...

Hiroyuki,

Thanks for taking the time to respond. I have little to no experience with direct flame roasting. My experience with it was not good when I tried my hand in the past. But I get your point of extended dry times as the little moisture coffee beans have, are to be retained later when doing the real roast as water is a good conductor of heat ..I might try your method soon . By the way I accidentally stumbled into this article which is in Japanese and with google translator I was able to make some sense of it ...whats your take as I cannot understand it fully ...Looks like he ran into unexpected success when he changed from direct flame to air roasting ?
Definitely some food for thought I believe ?

http://a4rt.com/coffee/837/


-Pete

Hiroyuki said...

Peter:
>Looks like he ran into unexpected success when he changed from direct flame to air roasting ?

Actually, No.

>Definitely some food for thought I believe ?

Unfortunately, not much useful info.

The title is:
珈琲焙煎 意図的に生豆の水分を残す
Coffee roasting Leaving moisture in green beans intentionally

Beginning:
珈琲焙煎機のドラムを直火式から半熱風式に変えたので、ローストプロファイル(焙煎の設定条件)の見直し作業を行っています。

Because I have changed the drum of the coffee roaster from a direct-flame type to a semi-hot air type, I am reviewing roast profiles (roast settings).

The end:
生豆の水分を抜き過ぎず、抜かな過ぎずのその狭間の絶妙なところに「スイートスポット」が存在するのかもしれません。
There may exist a "sweet spot" somewhere between not removing moisture from green beans and not over-removing it.

For information about semi hot air drums, visit this site:
http://www.discovery-cafe.jp/english/2_roasting/220-mechanism-of-coffee-roaster.html
and view under "Semi hot blast cylinder".

Lastly, I'm not a coffee geek in the first place. I believe that you can get useful information from relevant coffee-related forums.

Peter Gabriel said...

Thanks Hiroyuki for taking the time to answer and I am no coffee geek either ...I shall surely check the site you suggested. By the way when you get a chance kindly let me know why is direct flame better than air roasting ..I thought both uses convecting rather supposed to conduction . Thanks !

-Pete