Here’s some Coffee Basics

simple coffee science

At its simplest, making coffee is just about combining ground coffee and hot water.

People have different preferences and tastes though, so there’s no automatic formula to making a cup that YOU will enjoy – everyone needs to experiment and find what they like best!

There are some simple principles that can help you get more from your coffee, here’s a few of them:

The better the origin the more chance you have that it will taste good – this applies to both the coffee and the water.

Some people do make coffee with boiled spring water as they think it gives the coffee the best chance. That may be going way too far for most people, but it is worth remembering that the water you use will have an impact – using water that has gone through a water filter could be a good idea if you have one.

The coffee origin can be talked about for ever – but there is at least a very simple thing to remember: the fresher the coffee the better. So within the coffee making process it’s ideal to keep the coffee in the form of beans as long as possible before grinding – right up until you actually make the coffee in fact! Air is an enemy of coffee freshness – so when you grind the coffee it’s best not to do it days or hours in advance, but just as the water is boiling.

You can still get great tasting coffee from pre-ground coffee – but don’t keep ground coffee in the cupboard for months on end, and remember this thing about air being coffee’s enemy: keep your coffee in an airtight container and limit its exposure.

The water you use should be off the boil (best at90 to 95 degrees celsius) – certainly not boiling.

What’s next depends upon the coffee making method that you use: in fact the grind fine-ness of your coffee should really be different depending upon the coffee maker that you’re using.

Turkish coffee requires the finest grind (almost like powder), espresso makers very fine too, AeroPress generally uses a reasonably fine grind (like fine sand) as do stovetop makers and syphon devices. Automatic filter makers need something a little coarser but we’re still staying on the fine side with these.

A pourover coffee maker or a Chemex needs a grind on the coarser side (but not too much as the coffee grinds are in contact with any part of the water just briefly, as it flows through).

A Clever Dripper , a Cafetiere/French Press, or Cold Brew require the coarsest grind as the coffee will be seeping in the water for an extended period of time.

Once you’ve made your coffee, don’t leave the coffee standing – dispense it and drink it!! The longer it stands the more bitter it will become as the coffee grinds will have been in contact with the water for too long.

Hopefully those principles are useful in approaching your coffee making – remember to experiment and enjoy finding out the differences that result from changing some of the ways you make your coffee.

Oh, one last point – the ratio of coffee to water will be something that you decide for yourself – but it’s useful to start from the Speciality Coffee Association best brewing practices: 55g of coffee to 1 litre of water (which works out at about 14g for a small mug of 250ml, or about 18g for a large mug of 330ml).

View our speciality coffee selection and coffee making devices at artistrycoffee.co.uk

The Evolution of Coffee Culture in the UK: From 1st Wave to 4th Wave Coffee

Coffee Grinder and coffee cup - Photo by Tom Swinnen on StockSnap.io

Coffee has come a long way from being a commodity product to more of a cultural icon. In the UK, coffee culture has undergone a remarkable transformation, from the mass-consumption of instant coffee in the first wave to the specialty coffee movement of the third wave and onwards to the sustainability and innovation focus of the developing fourth wave. Let’s explore the history and development of coffee culture in the UK through the different waves of coffee.

1st Wave Coffee: The Beginning of Coffee Culture

Coffee was introduced in the UK in the 17th century in select coffee shops in major cities like Oxford and London – but it could be said that the first true wave of coffee in the UK began in the late 19th century with the mass production and distribution of pre-ground coffee. Coffee was primarily consumed as a commodity product, and instant coffee became increasingly popular due to its convenience. However, coffee shops also started to become popular social gathering places, and coffee culture began to take root.

The Second World War brought about changes in the coffee industry, with the introduction of rationing and the need for alternative products to supplement the limited coffee supply. Chicory became a common substitute for coffee, and instant coffee remained popular due to its convenience and affordability.

2nd Wave Coffee: The Rise of Coffee Chains

The second wave of coffee could perhaps be said to have began in the UK in the 1990s, with the arrival of coffee chains such as Starbucks and the expansion of Costa Coffee. These chains introduced to many people the concept of specialty coffee drinks like lattes and cappuccinos and focused on creating a “coffee shop experience” for consumers. The second wave was characterised by an emphasis on branding, marketing, and creation of coffee drinks as a cultural experience rather than just a beverage.

The growth of coffee chains led to the widespread availability of barista-made coffee and the popularisation of coffee culture in the UK. Coffee shops became popular places for socialising, working, and relaxing, and the demand for specialty coffee drinks continued to increase.

3rd Wave Coffee: The Emergence of Specialty Coffee

The third wave of coffee in the UK began in the early 2000s, with a focus on the quality and craft of coffee as a specialty beverage. The third wave emphasized the origin, processing, and roasting of coffee beans, as well as brewing methods that showcased the unique flavours and characteristics of different coffee varieties.

Specialty coffee shops and roasteries began to emerge, and the concept of direct trade relationships between coffee growers and roasters gained popularity. Consumers became more interested in the story behind their coffee, and the demand for specialty coffee beans and brewing methods continued to grow.

4th Wave Coffee: Sustainability and Innovation

While there is no official consensus on the definition of the fourth wave of coffee, some say that it involves a continued evolution of the specialty coffee industry beyond the third wave to involve a focus on sustainability and ethical practices throughout the supply chain. This includes environmental issues and social responsibility. It could also involve continued exploration of innovative brewing techniques, such as cold brew, nitro coffee, and alternative brewing methods like pour-over, as well as a greater emphasis on technology and automation in coffee production and brewing.

Coffee culture in the UK has evolved significantly over the past century, from the mass consumption of instant coffee to the specialty coffee movement of the third wave. While the concept of a fourth wave of coffee is developing, it is clear that the demand for quality, sustainability, and innovation will continue to shape the future of coffee culture in the UK.

You can check out all our coffees, including the stories behind them, and the social responsibility emphasis here at artistrycoffee.co.uk.

What’s in a bean? (or more accurately What’s in a coffee cherry?)

Ethiopian Green Beans

Coffee with the biggest caffeine hit is likely to have come from the robusta bean type. These coffees may be more likely to have a bitter taste and perhaps heavier earthier tones. Instant coffee is more likely to have been made from robusta beans to capture more caffeine in the granules. There are also several coffee shops that favour the robusta bean.

Robusta coffee beans count for around 25 to 30% of worldwide coffee production and the tree is more hardy and grown at lower altitudes (below 1000 meters) in higher temperatures (upto 30 degrees celsius). The robusta bean may be more likely to be circular shaped and with a straight line split down the middle. It tends to be cheaper, with a less pronounced aroma but more full bodied. Robusta can vary in quality due to growing conditions and processes, and there has been a movement to upgrade the reputation of the bean with more care and attention in the growing, processing and roasting techniques. Largely though robusta beans would be more inferior coffees – but if caffeine levels are the priority then with often double the caffeine of arabica beans there are some benefits!

The higher altitude grown (often 1500 to 2000 meters asl) arabica beans are usually sweeter, more flavoursome (fruity, floral, delicate, smooth) with a more pleasing aroma. They can be oilier and darker and have a more oval elongated shape with a probable split which is more S shaped. Most likely grown at temperatures of  high teens to low twenties celsius, and with more shade (in the company of a wider biodiversity of other plants).

There are many sub-species of coffea and there is a possibility that in future increasing the genetic variation may become important to protect coffee from vulnerability to disease and climate changes.

Coffee fruits are called coffee cherries and most move through a colour cycle from green, then yellowing, to red when ripe. The seed, inside the coffee cherry is what is used to roast and create our coffee drinks. In order to ready a coffee bean for roasting it has to go through processing to remove the skin and flesh of the coffee cherry (the pulp, the parchment and the silverskin).

In fact, inside the cherry – there are normally two parts of the coffee seeds which grow with a flat face facing each other – these are the faces that feature the characteristic split in the coffee beans we see.

A coffee seed (bean) before roasting is normally a yellowish green colour and known as a green bean: once roasted they gain their brown colour.

Science, Theatre, Artistry! Coffee making with the Hario Syphon

Hario Syphon Coffee Maker in use

There’s something of the science lab about making coffee with the Hario Syphon Coffee Maker!

You don’t need to understand the science to enjoy coffee making this way – and it’s not complicated, but it is incredible. Not understanding the science of air pressure, vacuums, and heat effects just actually makes it appear to be magic! And therefore enthralling.

The Hario Coffee Syphon is not based on new ideas at all – in fact the first syphon coffee makers are traced back to origins in the 1800s.

The thrill of seeing the water bubble up to the top chamber of the coffee maker is spellbinding. Then shortly after it will slowly seep back down into the lower chamber as brewed coffee. It really does seem like magic.

The device comes with a small alcohol burner which is the main control over the process. There’s a lower borosilicate glass chamber where you place pre-boiled water, and an upper chamber where the coffee grounds are placed (with a filter held in place by a clever weighting mechanism). The whole thing is held on a stand to hold the coffee maker above the alcohol burner. Can you see why it feels like a science lab way of making coffee?

Hario Technica Coffee Syphon 3
Hario Technica Coffee Syphon 3 available at Artistry Coffee

The water is heated further from below, and (here’s a Mickey Mouse bit of science) the expanding pressure in the lower chamber forces the coffee up through the connecting pipe into the top chamber where the coffee grounds are sitting.

This mixes the hot water with the coffee and begins the brewing process. If you can draw yourself away from being mesmerised by this coffee making device, you can help the effectiveness of the process a little at this point by stirring the water and coffee grounds in the top vessel.

The heat source now needs removing and covering, to extinguish the flame. This starts to reduce the air pressure below ( which has almost become like a vacuum – because the contents that were in the lower chamber are now in the upper chamber).

The reduced pressure below now gives the brewing coffee somewhere to go –  down!

So gradually the contents of the upper chamber will sink into the bottom glass vessel – straining through the filter in the middle section to give a clean, clear brew.

The top section then needs removing, as its work is done – and the stand that the bottom glass vessel is held by becomes the pouring handle to pour out your coffee!

See the Hario Coffee Syphon at Artistry Coffee – we stock the 3-cup version.

Always follow the manufacturer’s instructions, which give full explanation of the device, how to use it and any safety requirements.

Where does the best coffee originate?

Redemption Roasters Coffee pack and label - stocked at Artistry Coffee

Coffee is grown in many regions around the world – but mainly with the commonality that the coffee growing regions are within the band of the Tropics either side of the Equator – between the Tropic of Cancer in the  northern hemisphere and the Tropic of Capricorn in the southern hemisphere.

It is not just due the proximity to the Equator and the more consistent and moist tropical climate patterns that this produces, but also to the higher elevations present in Central and Southern America, tropical African regions and South East Asia and parts of the Middle East.

Coffee grows better at higher elevations (often 1,000 to 2,000 metes above sea level) – particularly the smaller beans of the Arabica variations which have generally been prized as the better beans, though there can be quite a variation in taste, flavour profile and production technique.

A bit like wine, coffee tastes different depending upon the bean, the soil and biodiversity environment, as well as the climate and the techniques of cultivation, preparation for roasting, washing, drying, etc.

Central and South America are the powerhouses of worldwide coffee production, with Brazil the biggest of them all.

Africa (the Sidamo region of Ethiopia) is often credited as the birthplace of human coffee consumption.

South East Asia and the Middle East also boast many coffee producing nations including their largest producers Indonesia and Vietnam with flavours thought to be more earthy and bitter.

Coffee roasting is usually done more locally to consumption – and ideally within just weeks or at the most a few months from consumption. Its best to grind coffee just before you consume it, if you have your own coffee grinder (see our range of handgrinders), to allow the coffee bean to contain the flavour until you release it.

There’s lots to discover about coffee beans, their flavours and characteristics – the best way is to try some different beans and take a few notes as you drink your coffee to create your own taste notes and get an idea of what your enjoyment of coffee is driven by.

There are many smallholder farms in amongst even the biggest coffee producing nations – we stock Redemption Roasters coffees who select coffee beans with the social responsibility agenda in mind and always on the lookout for an exceptional coffee.

See our range of coffees and their stories – coffees with social responsibility.

Which way would be your preferred way to use the amazing AeroPress coffee maker?

AeroPress coffee maker Series 5

The AeroPress is a brilliant coffee maker which can produce consistently good results, with a couple of different options for how you use it.

The classic method is the quickest which is simply..

coffee – water – stir – press.

The AeroPress packaging still says stir for 10 seconds and push for 20 seconds – it really can be that easy to make great coffee. You can watch a video of Artistry’s Sarah demonstrating this method.

Then there’s the inverted method which is a little slower and more intricate, but the favoured method of baristas worldwide.

This involves pouring the ground coffee and the water into an inverted AeroPress, stirring and then letting the coffee brew for a few minutes.

Then adding the filter and mesh cap and quickly turning over to press the coffee through into a mug below.

This allows for lots of experimentation with different grinds on the coffee and different brew timings.

So you can decide if you want a quick well-made coffee that beats instant coffee hands down – or to take more time over the coffee and the experimentation to perfect your own brew technique!

There’s now a Series 5 version of the AeroPress, which has shiny gold lettering and a cloudy brown look to it.

Colours and materials used have changed over the years as the design has been adjusted from the original clear with blue guide marks.

The journey gets more serious? ….starting to discover pour-over coffee!

Hario Buono, and V60 Ceramic Dripper from Artistry Coffee

So for many of us coffee is a part of our life whether we think about it or not!

The question do you want a coffee has probably already been said to you or by you today, even if only in your mind to yourself!

However, to start to pay more attention to what your cup of coffee contains can be the beginnings of a journey that gradually increases in intensity.

There was a point when – rather than using drip-filter by accident (i.e. without realising) or french press because it sat there (thinking it was just a cafetiere: which of course it is!) – the idea of hand-brewing coffee became more than a means to an end, it became an enjoyment in itself!

This started with a V60 Ceramic pour-over: a cup-like thing with a conical shape and a hole in the bottom. You place a filter paper within it then add ground coffee and pour hot water over the coffee which then drips through to a mug sitting below.

This is a slow coffee making process to savour: not perhaps the best method to use if you’re in a rush!

But this is where a real enjoyment in coffee making started for me and my wife. The process of thinking about the coffee and what it was doing as you were making it became interesting, and the time taken in the pour-over coffee making started to be a relaxing routine.

Starting with the same ground coffee we were using from the supermarket, we enjoyed “blooming” the coffee by pouring a small amount of hot water for about 15 seconds to let the Coffee grounds swell; then pouring hot water gradually over the coffee for another 2 to 3 minutes whilst seeing gasses from the coffee bubble up a little.

Hario V60 Pour-Over Coffee Maker available from Artistry Coffee
A V60 Pour-Over Coffee Maker
Pour-Over Coffee Making Equipment available from Artistry Coffee
Making Pour-Over Coffee

The aroma from the coffee when making it, as the coffee interacts with the hot water and then drips though, adds to the pleasure – and this is heightened because of the slow process of the pour-over coffee making. We found that the coffee was much more pleasurable as black coffee than we had ever experienced before: which then took us to a new place in coffee appreciation.

Discovering pour-over coffee making was a great find, and we recommend it to all – when you have time to savour the process!

Water Temperature Experiments for Coffee (6): …

Recording Temperature of Poured Water

This series of posts started from a fairly simple question in my head – what is the rate of cooling of water from boiling – to have some sense of what temperature coffee making is conducted at when there are no thermometers to hand! It has turned into a rather more complex investigation than first thought – but has been at least a little fun along the way. Here, were close to the end of my write-ups!

We’ve already covered that when transferring water after boiling from an electric kettle into another vessel such as a Buono kettle (in order to achieve greater accuracy for pour over coffee making) there seems to be about a 3 or 4 degree Celcius loss of temperature straight away.

So this post is about the expectation that as the water is then poured from the Buono onto the coffee grounds themselves there is likely to be another (notable?)drop in temperature.

That was the expectation and indeed has been exactly what I observed in my experiments.

In order to attempt to measure this effect, I rigged up a set-up (imperfect, but trying to get close to something realistic) where I could pour water from the Buono spout directly onto the bulb of the thermometer. That’s the closest I’ve been able to construct to something reasonably meaningful.

I conducted most of my previous efforts over a 10 minute observation window – however the idea of pouring water from a Buono kettle for 10 minutes was never going to be achievable – I did try and control it well, and managed around 5 minutes each time, which I think was a good achievement (also meant my rate of pour should have been similar on each attempt).

Chart of Observed Temperatures (time from Boiling Point)
Top Line (darker) : Observed Temperatures in Electric Kettle
Next Line (mid-tone): After being poured into Buono Kettle
Bottom Line (lightest): Temperatures of the Pour

The temperature within 30 seconds had dropped to 90 degrees Celcius, but took till almost 6 minutes to drop the next 5 degrees – by which point it was almost equal to the observations of the temperatures achieved in the Buono kettle itself(with no pouring).

That line on the chart that resulted did puzzle me at first – although the greater initial drop in temperature made sense, the slower rate of decline in the following minutes than observed in the kettles did seem odd ( I haven’t worked all the way through this yet, but I think one of Newton’s Laws does help – I need to look into that a bit more, and will try and write something in a few days).
What also seemed odd is that the water poured from the Bouno (having been poured in the Bouno from the electric kettle) was at a lower temperature in the earlier moments of observations than the water in the open-top vessels.

Observed Temperatures from Boiling Point
Top Line (darker): Temperatures in Electric Kettle
Next Line (mid-tone): After being poured into Buono Kettle
Bottom Line (lightest): Temperatures of the Pour
Yellow Line: Temperature in open-top container

OK – only for 30 seconds, but that it crossed the line, then crossed back again made me think that this science lark was just far too complicated!

But here could perhaps be the most important thing to understand from these experiments – that the pour itself is where the temperature changes the most (pouring from the kettle used for boiling, into another vessel in the first place, and from the pouring vessel onto the coffee).

And therefore different styles of pour, durations of pour, or methods of dealing with the water will mean that the temperature, in effect, on the coffee is different.

This is where the water is coming into most contact with the air (or perhaps more importantly (scientifically) the much lower ambient temperature) and so is losing the most heat.

So I guess one of my biggest conclusions is that when we’re talking temperature we may or may not be talking the same thing – the temperature of the water can change greatly quite quickly depending on how it is transferred from the boiling vessel to the coffee.

Water that is the same temperature for 2 different coffee making techniques at the starting point could actually be at very different temperatures when hitting the coffee grounds seconds later.

This coffee making really is both an art and a science!!

please note: boiling and hot water can be dangerous if not handled with care!
(despite the haphazardness of some of my approaches above, I did take some care and would suggest anyone else does the same: and children should be accompanied by an adult)

Water Temperature Experiments for Coffee (5): ….

Hot Water onto Coffee Grounds

Interim Conclusions …?

Instead of being one simple set of experiments to while away an afternoon and get the brain cells working – this little exploration has actually turned into a set of experiments and blog notes and pseudo scientific activity that has occupied rather more than the initial expectation!

Where we’ve travelled so far, I think, is that the temperature of the hot water as it hits the coffee could vary perhaps rather a lot – affected by all that can happen between the boiling of the water and the drips hitting the coffee.

What I seem to be able to conclude so far is that if the water remains in the kettle it retains its temperature much better than if poured into another vessel. If this other vessel is closed top (e.g. Buono kettle) the temperature will perhaps drop 3 to 4 degrees on the initial pour from the kettle, then hold at a slower rate of decline than if poured into an open-top vessel (where over a few minutes the temperature difference may easily be 10 to 15 degrees Celcius).

All of that fairly logical (and some would say obvious or a matter of common sense perhaps), but I’ve found it rather interesting to be able to place some (amateur) quantification on what’s going on, and helpful to think through what may be affecting the readings.

But the key issue is perhaps what temperature the water is as it hits the coffee. And for my own normal coffee making at home, this involves first pouring the boiling water from the electric kettle into the Buono, and then pouring from the Buono onto the coffee grounds themselves.

So the idea that there might be a second heat loss as poured from the Buono kettle seems to be a logical expectation, and that’s exactly what we get – but the results did puzzle me at first.

(I’ll write that up next post…..)

please note: boiling and hot water can be dangerous if not handled with care!
(despite the haphazardness of some of my approaches above, I did take some care and would suggest anyone else does the same: and children should be accompanied by an adult)

Water Temperature Experiments for Coffee (4):…

Buono Kettle with Thermometer

I started out looking at the temperature that boiled water reaches when it is left to cool – to think about having some guide for coffee making when just getting on with it rather than trying to measure every element, every time.

I quickly realized that it wasn’t as simple as that, and the water temperature depends on lots of things that can go on from the point of boiling.

So being in semi-scientific mode (a real scientist could probably tear my methods apart), I went off on an exploration of water temperature with some kitchen table experiments.

Having had a fairly simple start – by simply pouring boiling water into a jug and recording temperatures for 10 minutes. I then figured I needed to think about much more:

  1. If the water is held in vessels of different material
  2. If there is a smaller surface area, especially smaller top of the water, from which the water may lose heat.
  3. What happens when the water is not transferred from the water boiler (kettle).
  4. With those, I tried measurements in a ceramic mug rather than plastic jug which sort of covered 1 and 2 above. Nothing much to report there though.

    Measuring the water in the kettle itself was dramatically different (upto 15 degrees Celsius different at the same time since boiling in my observations).

    But still more to think about: The way I usually make coffee is either to pour first into a Buono kettle and then pour onto the coffee (either in one go into an AeroPress or over time as a drip filter). So I needed some other answers

  5. What happens to the water temperature in the Buono kettle?
  6. And perhaps most importantly, what is the temperature of the water as it actually hits the coffee?

To answer question 4 was relatively simple – simply pour the water straight from the kettle into the Buono and take the temperature readings from there. Answering 5 is a lot more complicated (that’s for next time).

The observations showed that there’s a cooling that goes very quickly, reducing the temperature by around 3 or 4 degrees Celcius, when the water is first poured into the Buono vessel – and that this temperature difference is then roughly maintained for the duration of the observations.

Darker line: observed temperature in boiling device (electric kettle), Lighter line: temperature in Buono Kettle (poured into from electric kettle)
Darker line: observed temperature in boiling device (electric kettle), Lighter line: temperature in Buono Kettle (poured into from electric kettle)

The observed temperatures from the Bouno kettle is the lower (lighter) line on the chart and you can see it approximately holds the relationship with the line above (the observed temperatures from the boiling kettle).

So this is logical, and in line with my first thoughts – that the initial pour into another vessel cools the water by a few degrees from boiling point (whether it be pouring into the plastic jug, the ceramic mug, or the Buono kettle). But the Buono clearly holds the temperature in slower rate of decine than an open topped vessel (this is science of some sort, but not really rocket science! Or perhaps it is!!!).

So I feel that this has all been helpful in coming to some greater understanding of what happens to the temperature of the boiled water, before it is poured onto coffee – but doesn’t get us to the answer of what is happening as the hot water it hits the coffee grounds (so that will be looked at next time….).

please note: boiling and hot water can be dangerous if not handled with care!
(despite the haphazardness of some of my approaches above, I did take some care and would suggest anyone else does the same: and children should be accompanied by an adult)