滴漏式咖啡真的很棒!可以看著手沖時的水流優雅地留下,而沖得好的咖啡就像澄澈如水晶般的液體,最棒的是我們人人都可以自己在家自己沖。

但看起來很棒卻沒有看起來那麼簡單,有許多人說一杯滑順又穩定品質的咖啡需要攪動。那什麼是攪動?專家對於攪動過濾式咖啡怎麼說?而最重要的,攪動後真的有比較好喝嗎?讓我們看下去。

 

coffee brewing

使用Hario V60沖煮,來源:Yara Tucek via Flickr, CC BY 2.0

 

什麼是攪動?

讓我們從最基礎的說起,我們都知道過濾的過程有兩個程序:首先用少量熱水浸濕咖啡粉,在約半分鐘的時間,達到悶蒸的效果;其次,才將剩餘的水注入到咖啡粉上,讓咖啡能慢慢滴到承接的容器中。

但過程當中還有攪動(也有人稱為湍流),就像在你很忙時你的弟弟妹妹出現在旁邊鬧你一樣,只是沒有描述得那麼負面,噢,而且其實你就是扮演弟弟妹妹的角色。

簡單來說,攪動在沖煮的過程是一個溫和的干擾,有很多種攪動的方式,每種都有其理由,在我們看如何攪動前,先來看你想要達到什麼沖煮的目的。

coffee brewingKalita Wave沖煮時的悶蒸,來源:Olgierd Rudak via FlickrCC BY 2.0

 

 

長話短說-攪動可以達到什麼目的?

我們都在設法將咖啡的好味道帶出來,這表示我們需要達到一致的萃取,如果不同區塊的粉其萃取率都不一樣,你將無法操控或複製杯中的風味。你的咖啡將會因此混合了萃取不足(臭酸味)以及過度萃取(苦味)的元素,當然也會包含良好萃取的元素:甜味以及平衡度佳的咖啡。

 

 

coffee brewing

製作手沖咖啡,來源:0102oxy via Pixabay

 

在手沖或義式咖啡中一個常見的議題就是通道效應,水總是會往阻力較小的地方流動,因此如果咖啡粉並不是均勻堆疊或浸泡,水就會在咖啡粉中製造出通道,而這將使靠近通道的咖啡萃取較多程度。

通道效應會因為注水速度太快或不穩定的手法而產生,例如,這會在濾紙留下很高且很乾的咖啡粉牆,而這些則是無法萃取的部分。有些人也使用了點滴注水法(使用多次少量水取代長注水的手法),則可以避免這種粉牆的出現。

換句話說,攪動會讓咖啡粉分散,確保萃取的均勻度,當然這不是唯一用來維持一致性萃取的原因。如果你想要讓每天沖出來的咖啡都一樣好喝,試著標準化你的沖煮參數,包含:粉量、水溫、沖煮濾器、注水的路徑與速度、水質、研磨粗細與沖煮時間。

coffee brewingKalita Wave濾杯中研磨好待沖煮的咖啡粉,來源:Olgierd Rudak via Flickr, CC BY 2.0

 

 

如何攪動手沖/滴漏式咖啡

有幾種攪動的方式,其中最常見的就是攪拌,有些咖啡專家都推薦這種攪拌法,諸如Barista HustleMatt Perger,以及知名咖啡訓練師、著名咖啡書的作者Scott Rao。你可以在悶蒸後直接攪拌咖啡粉,或是在悶蒸剛開始時就攪拌,也可以在後段沖煮時攪拌。

你也許還聽過擾流,這表示在注水的最後,將水注到濾杯的邊緣,從邊緣將頂層的咖啡粉再沖入咖啡液中。

攪動還可以有幾種形式,像是點滴滴水、側漩、控制水的流速與水量等等

coffee brewing

 

注水的力道可以攪動咖啡粉,來源:Pål-Kristian Hamre via FlickrCC BY 2.0

 

 

專家都使用什麼技巧?

 

早先我們在說攪動的重要性時有提到Matt PergerScott Rao,我們在這裡來看他們用什麼手法吧。前幾年Matt Perger獲得2012世界沖煮大賽的冠軍時,他分享了一部V60濾杯沖煮手法的影片。你可以分解他的動作,會注意到他在悶蒸後大力攪拌,之後控制手沖的方向(不斷擴大的同心圓),用這些力道避免粉牆,有節奏的沖煮,並在結束前拉起並輕震濾杯,讓粉床呈現水平狀。

 

在影片中還可以看到他使用了Rao Spin,這是利用沖煮時讓水以螺旋狀旋轉,因而讓水更平均的下降,而這名稱就是取名自Scott Rao

即使Rao並非這技術的發明者,但這種技術是從他的工作中發展出來的,而他也支持這種手法,據Rao說「這技術將沖煮結尾的通道效應最小化,在每次沖煮創造了平坦的粉床,這技術太棒了,我甚至希望是我發明了它」。

也可以透過輕輕搖動濾杯來創造Rao Spin,以下由Rao拍的七秒的影片展現了這部分。

 

 

 

所以我們如何應用?

以上這些你都可以嘗試看看,不論你是咖啡師、咖啡愛好者或只是初學者都可以試試看,在沖煮時攪動,下一輪再試試不要攪動,之後自己測試其中的差異,或是跟朋友分享,並將其展示給你的客人們。

找出其中的差異,品嚐咖啡中的細微變化,並變換研磨粗細與沖煮手法,之後找出最好複製的方法,讓沖煮結果可以維持一致。

第三波咖啡風潮的咖啡其最美好的地方在於實驗,在當中作些攪動的實驗,看看這種方法適不適合你。

 

 

Written by Sam Koh.

Original source:

 

https://www.perfectdailygrind.com/2017/08/agitation-make-filter-coffee-better/

 

 

 

以下為原文

 

 

 

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What Is Agitation & How Does It Make My Filter Coffee Better?

 

Filter coffee is great, isn’t it? The calming drip of the brew, the elegance of the pour-over process, and the coffee itself – a smooth cup with crystal clear clarity. And even better, we can make this coffee ourselves at home.

But like all great things, it’s never as simple as it looks. There are many who say that a truly smooth, consistent cup of coffee requires agitation.

So what is agitation? How do the experts advise agitating your filter coffee? And most importantly, does it guarantee a better cup? Let’s find out.

 

coffee brewingBrewing a Hario V60. Credit: Yara Tucek via FlickrCC BY 2.0

What Is Agitation?

Let’s start with the basics. We know that the filter process has two steps: one, wet ground coffee with a small amount of hot water so it blooms for approximately half a minute; two, continue to pour the remaining water over the grounds so that coffee slowly drips into our collecting vessel.

But then there’s agitation (also called turbulence). It’s kind of like having a younger sibling prod at you while you’ve got stuff to do – but not quite as negative. Oh, and you’re the sibling.

Simply put, agitation is a mild disturbance – hence the term “agitation” – of the coffee grounds during the brew process. There are many ways to agitate coffee, all with their own advocates. Before we look at how to agitate, let’s look at why you’d want to.

coffee brewingA Kalita Wave blooms. Credit: Olgierd Rudak via FlickrCC BY 2.0

Long Story Short – What Does Agitation Do?

We’re looking to get the best flavors from our coffee grounds, and this means we need consistent extraction. If different grounds experience different rates of extraction, you won’t be able to control the final flavor profile – or replicate it. Your coffee will have a mixture of under-extracted (sour) and over-extracted (bitter) compounds, as well as those perfectly extracted, sweet, balanced notes.

coffee brewingBrewing a pour over. Credit: 0102oxy via Pixabay

One common issue that can occur in filter (and espresso) coffee is channeling. Water always takes the route of least resistance. Therefore, if the coffee grounds are unevenly piled or unevenly soaked, the water will create channels through the grounds. It will extract the coffee near the channels more than the rest.

Channeling can be exacerbated by pouring water too quickly or in an irregular motion. For example, this can leave coffee grounds “high and dry” on the filter, where they can’t be extracted. Some people also find that pulse pouring (i.e. doing several small pours instead of long ones) can help avoid these high-and-dry grinds.

Agitation, on the other hand, will disperse grounds and, in doing so, help ensure even extraction. Of course, it’s not the only factor that is important for consistency. If you want to make the same great-tasting coffee every day, try to also standardize your dose, brew temperature, brewer and filter choice, direction and rate of pour, water quality, grind size, and brew time.

coffee brewingDry ground coffee sits in a Kalita Wave, ready for brewing. Credit: Olgierd Rudak via Flickr, CC BY 2.0

How to Agitate Pour Over/Filter Coffee

Agitation can occur in a few forms, one of the most common being stirring. It’s been recommended by experts such as Matt Perger of Barista Hustle and Scott Rao, trainer and writer of renowned coffee books including The Professional Barista’s Handbook and Everything But Espresso. You can stir your coffee grounds straight after pre-wetting your brew, before it has begun to bloom, and also following the final pour.

You’ll also hear people talk about a flush. This means pouring the last milliliters of water along the very edges of the brew, where it can “flush” any high-and-dry grounds back into the mix.

Agitation can also happen through other actions such as tapping the dripper, swirling the brew, controlling the rate and heaviness of pouring, and more.

coffee brewingThe force of your pours can agitate the grounds. Credit: Pål-Kristian Hamre via FlickrCC BY 2.0

What Techniques Do The Pros Use?

Earlier I mentioned that both Matt Perger and Scott Rao have spoken about the importance of agitation. Let’s take a look at their preferred techniques.

Shortly after winning the World Brewers Cup Championship in 2012 with a V60, Matt Perger shared the video below breaking down his technique. You’ll notice he stirs the bloom (“stir it like a bandit”), controls the direction of his pours (ever-expanding concentric circles), uses the force of them to prevent high-and-drys, pulse pours, and finishes by lifting and tapping the V60 to create a level bed with minimal clumps.

You’ll also have noticed that he refers to a Rao Spin – something that causes the water to spiral in the brewer and more evenly soak the water. As you might have guessed, it’s named after Scott Rao.

While Rao didn’t invent the technique, it’s based on his work and he’s also endorsed it. In his words, “it minimizes channeling during the final drawdown and creates a flat spent bed every brew.  It’s so good, I wish I had invented it.”

It’s also possible to manually create a Rao Spin through slightly agitating the dripper. Here’s a seven-second video from Rao that demonstrates this:

Oh, and he’s also a strong advocate of agitating the pre-brew and the final pour, just like Matt Perger.

 

So What Does This Mean For You?

All this means that you should try it. Whether you’re a barista, a coffee geek or just starting out, try it. Try brewing with agitation, and then try it without. Test it yourself, share it with friends, and sample it with your customers…

Find out the differences, taste the nuances in your coffee, and play with the grind size and pouring methods. Then find the best way to replicate this, so your results are consistent.

 

The wonderful thing about third wave coffee is the ability to experiment. So jump straight in, experiment with agitation, and see if it works for you.