Extraction Variables


The regrettable reality is that most people believe that coffee is just a push of the button. Any effort that goes into coffee making is jus lost time. I remember another conversation with a fellow barista who told me he believed making espresso just implied pressing a button, before he started working in the field.

However, I was grateful to my partner as I understood how crucial it was to produce this piece on coffee extraction. So continue reading to find what really goes into coffee making and what other skills are required to make scrumptious coffee, apart from excellent button pushing skills!

What Is Coffee Extraction?

The advancement of coffee extraction

Coffee extraction is the procedure of dissolving tastes from coffee grains into water. It sounds extremely straightforward in theory, I grant you. Regrettably, if we put raw, green coffee beans into water, very little occurs. Gradually we have discovered that there are different elements which increase the level of extraction, which indicates more coffee properties or Overall Dissolved Solids (TDS) in the final cup of coffee.

The first of these aspects is heat. Our forefathers extremely rapidly recognized that putting raw coffee beans in hot water developed more of a response compared to soaking raw beans in cold water. They found that, if they didn’t heat the water, they needed to leave the coffee beans soaking for a lot longer in order to get any sort of taste at all in their brewed beverage. This highlights the 2nd element that influences coffee extraction: time. The longer the of time the coffee is in contact with water, the more flavors it extracts.

Nevertheless, this original coffee drink was still remarkably disappointing and tasted essentially like the bitter plant that it was. Those ancient baristas needed to discover a method to increase the level of extraction from the coffee. Then one genius probably thought: if warm water draws more properties from the bean, then certainly it stands to reason that warming the beans over fire prior to putting them in hot water might release more of the coffee bean properties?

Eureka! Cooking or roasting the coffee beans prior to boiling them in water was the crucial to coffee preparing as we understand it today. This unlocked an universe of coffee for those pioneers. When we roast coffee we soften the internal cell structure of the coffee bean which permits us to extract even more properties and flavors from the coffee bean.

This was the method coffee was most likely extracted for several years and years. Ultimately, some smart coffee lover had the idea of squashing the roasted beans and preparing this ground coffee. Grinding coffee is the last primary factor which greatly increases the extraction of TDS from coffee beans. Grinding coffee increases the surface location of the coffee that touches with the water, therefore increasing extraction.

So there you have the three primary elements that affect coffee extraction:

  1. Grind size
  2. Heat
  3. Time

We can break these elements down much further however for now let’s stick with these 3 headings. All elements in coffee brewing are interdependent. If we change one aspect, it impacts the others and we have to change them as well. I’ll talk about this in more detail a bit later.

Over extraction and under extraction

Primal coffee drinkers became so proficient at extracting the coffee properties that they began going too far. They recognized that it was possible to have too many dissolved solids in the drink, altering it from a delicious beverage to something bitter, terrible and undrinkable. There is in truth a sweet spot for extracting coffee. In the early days of making coffee with raw green beans, the coffee was under extracted. Ultimately, when all of the coffee making aspects were determined and included to the process, coffee started to be over drawn out.

Clive coffee highlights how different coffee solids and flavors are extracted in a particular order when preparing. Fats and acids are extracted initially, then sugars, and lastly plant fibers. The goal is to brew the coffee for long enough to get a perfect balance of these compounds in the cup, but not long enough to draw out the undesirable, bitter tastes.

Therefore, various levels of extraction result in different tastes in our coffee

. Under extraction If we don & rsquo; t apply enough of one or more of the extraction elements, we will get a coffee that is under extracted. For example, if the ground coffee isn & rsquo; t in contact with boiling water for long enough, the coffee will be under extracted. Under extracted coffee tastes sour, salty and does not have sweetness, as the sugars have actually not yet been extracted to harmonize the oils and level of acidity.

Over extraction

If coffee is over extracted, nevertheless, it will taste bitter, due to too many of the bitter plant fibers being extracted from the beans. Counter-intuitively, these plant fibers are the only properties that can be drawn out from raw coffee beans without the addition of heat, which is why green coffee beans taste extremely bitter and unpalatable.

The extraction sweet spot

That perfect extraction point that we are going for will yield a drink that is sweet, with suitable acidity and a long finish ; the finish being the immediate feeling that we experience after taking a sip of the coffee.


So, for all modern-day types of coffee brewing, heat, time and grind size are all aspects that require to be considered when preparing a cup of coffee. In some cases one element can’t be adjusted for a particular reason for a specific brewing technique. Therefore, the other elements have to be adjusted to harmonize with the set factor. Let & rsquo; s examine every one separately. Grind At a fundamental level, the finer the coffee is ground the more coffee is extracted. This is due to the increased surface area that touches with the water.

With every coffee making technique, the grind size is chosen based upon a variety of parts.

These all need to be thought about when looking at the grind for a brew.

With drip coffee, the grind can’t be too great otherwise the water would take too long to pass through the filter.

With French press, the filter screen is much bigger than a paper coffee filter in basic French pots. This means that the grind usually has to be coarser for French press than for filter coffee.

On the other hand, espresso has the added element of pressure during preparation, which further accelerates the extraction process. The grind therefore needs to be much finer for espresso due to the added force of the pressure forcing the water through a smaller space in between the coffee grounds, at a quicker speed.

Finally, cold brew coffee is ground coarse to assist the water leak quicker through the coffee grinds. Due to the much longer extraction time, great ground coffee likewise tends to be over drawn out when cold making.

Grind size can be changed minutely for all preparing methods in order to discover that ideal extraction. Nevertheless, all coffee making techniques have a standard grind size to follow. The grind size that allows for best extraction for each approach has been painstakingly discovered over the duration of decades.

Grind sizes for standard preparing methods are as follows:

  1. French press - Coarse
  2. Percolator - Coarse
  3. Cold brew - Coarse
  4. Drip - Medium grind size
  5. AeroPress - Fine
  6. Espresso - Extra fine
  7. Turkish coffee - Powder

Contact Time

As with finer grind, longer extraction time equates to higher extraction. Several making approaches have a particular required steeping time.

For example, Drip coffee makers have actually a standard set time that they take to brew coffee. This means that the grind size and heat need to fit with the set extraction time in a drip coffee machine. In drip coffee this equates to a medium grind size and water that is nearly at boiling point.

The ideal time for standard espresso extraction is between 20 and 30 seconds. The grind size and the temperature are therefore minutely calibrated in espresso preparation so that an espresso is pulled out within this time frame.

Cold brew doesn’t apply heat in the preparing process at all. For this reason, cold brew needs a a lot longer period for extraction compared to hot coffee brewing. The longest time for most hot preparing techniques is around 5 minutes. Cold brew takes between 12 and 24 hours to draw out appropriately, which is a significant big difference.

Water Temperature

Temperature level (heat) is the last aspect that increases the rate of extraction. The hotter the water, the quicker and higher the extraction. Therefore, if there is currently a higher level of extraction from a specific preparation technique due to other previously mentioned variables, the water temperature doesn’t need to be as hot.

Espresso coffee has a fine grind and a fast extraction time due to the addition of pressure. For that reason the water temperature level requires to be a little cooler than for other making techniques in order not to over extract it.

Filter coffee water needs to be hotter to encourage more of a response with the coffee, due to the absence of pressure.

Pour over coffee and French press coffee require to be hotter again. This however is mainly due to the direct exposure of the water to the air. The open air nature of these preparing approaches causes the water to cool quickly, which is neutralized by preparing with water at a higher temperature.


Although I didn’t include roasting as an element that influences extraction, it is very much something that needs to be gone over here; so much so that it gets its own section. A coffee extraction recipe will always have to be changed for the type of coffee roast you are utilizing.

As with the extraction procedure, coffee beans can be roasted differently in order to encourage higher or less extraction. The main element that we are discussing when it comes to roast, is time.

The longer the coffee bean is roasted, the more soluble solids are released from the bean and are therefore extracted simpler during coffee brewing.

This is the reason that dark roasted coffee is generally believed to be stronger than light roasted coffee. This belief was established by people who use the same preparing recipe, regardless of roasting time. Coffee that is roasted for longer is extracted quicker, therefore it stands to reason that dark roasted coffee requires less of each brewing factor in order to extract efficiently. This means less time, coarser grind and cooler temperature levels. If preparing factors are adapted to compensate for a darker roast, dark roasted coffee can be prepared to be the very same as or weaker than a lightly roasted coffee, and vice versa.

So, hopefully, I’ve convinced you that brewing an excellent cup of coffee involves more than great quality devices and slick thumbs for button pushing. With any luck, you have actually also found out a little bit more about coffee preparation which will allow you to make your home brew that bit more scrumptious!

Additional information on and coffee brewing: Click for more