Understanding Extract Verb/Extract
“ Extracting ” is a simple word that refers to the act of taking something out of raw material. In the case of coffee, “extraction” is the method of removing dissolved compounds from the coffee beans using water.
Quite simply, however, it is difficult in that people use the word “extracted” to both refer to how the coffee is extracted as well as to describe what has been extracted. We’ll just talk about the latter here, using this word to describe the things we take away from coffee.
This is a mechanical way of saying coffee if you haven’t calculated extraction before – to make it easier to understand, imagine that after making a cup of Espresso, you continue to boil the cup of coffee. coffee until all the water has evaporated and only a brown powder is left. All that brown powder originally came from the ground coffee we put in the machine.
If we weigh that amount of brown powder and express it as a percentage of the original mass of the coffee, that is the percentage of extraction (or Extraction Yield). At first glance, this may seem like a somewhat arbitrary measurement, but it is actually one of the most powerful in the coffee world.
Research over the past few decades has shown that for all types of coffee, roast level, and brewing method, people almost unanimously prefer coffee with extraction between 18% and 22%
In summary, Extraction is considered the most important and least understood aspect of the coffee-making process. That’s everything. Without extraction, you don’t even get a cup of coffee. This is the super simple definition of Matt Penger, a two-time World Champion Barista and founder of Barista Hustle.
When you mix coffee and water, a lot happens. The first and most obvious of all is that water will dissolve a lot of the coffee’s flavor. These soluble flavors make up (almost) everything you taste when you drink a cup of coffee.
Where does the extract come word? Extract
In order to turn coffee beans into something we can use for brewing, we have to provide enough heat so that (countless) pyrolysis reactions can take place & transform the flavors in the beans. The heat of the roaster plays an important role in this process.
First, the heat evaporates any moisture trapped in the coffee. As moisture continues to escape from the beans, the plant fibers that make up the structure of the coffee will become dry, hard, and brittle. If you roast too long, the vegetable fibers will continue to break down and most of the oils in the coffee will push to the surface and begin to oxidize.
High heat will reduce complex sugars ( long-chain carbohydrates ) into simpler sugars (short-chain carbohydrates), making them taste better.
As the roasting process develops, these sugars will begin to transform into caramel, giving the aroma of brown sugar (so we always try to harvest coffee that is ripe enough – to accumulate the necessary amount of sugar). required for the reactions of the seeds in the roaster).
If the roasting process is pushed too far, these sugars will carbonize, and the flavor will change from sweet and complex to burnt and smoky. When the heat is increased, more acids in the coffee will also be decomposed, some other acids will be produced.
If you stop roasting too soon, the coffee will have a lot of acids, if it continues to roast, the acids will eventually break down completely and the coffee will taste pale and burnt. Most coffee roasters aim to balance the acidity levels in your brew so it won’t develop too acidic or too “burnt”.
With a medium roast, about 50% of the original citric acid content will be lost. Meanwhile, Lactic Acid is very low in green coffee, to the point of being undetectable. But after 6 and a half minutes of roasting, it has increased to 1.4g/kg.
How does the extraction happen?
Dictionary English Video Extract
To make any drink from coffee, we will take ground coffee and throw it in the water. Why water? Mainly because water is an excellent solvent. At the molecular level, water has a polar arrangement – two positively charged (+) hydrogen atoms on one side and a negatively charged (-) oxygen atom on the other.
This makes it super attractive for a wide variety of molecules. In fact, it is so attractive that it will break the bonds of other molecules, causing them to dissolve in water. If you heat water, all of its molecules will start to move rapidly, making it an even more effective solvent.
So good water & good coffee – are all you need to make a good cup of coffee. In almost any brewing method – including espresso, filter, cold brew, or French press – the general principle is the same.
Take the roasted coffee, grind it into small pieces and add water. When the water touches the coffee, it will begin to separate out flavor compounds. Regardless of the method, water will always extract the different flavor compounds in order: Acids and fats first, then sugars, and finally vegetable fibers. From a sequence of events, it looks like this:
Sour / Oily – Sweet / Sugar – Bitter / Light
- The first compounds extracted from coffee are acids and fats. Acids, which contribute to the sour taste, are the simplest compounds – molecularly. So water can easily dissolve them into liquid coffee. The fat in coffee, which contributes to its texture and viscosity, is not simple, chemically. Instead, they are hydrophobic and are easily washed out of ground coffee. In addition, more aromatics (lighter molecular structures) such as floral and fruity aromas will be extracted at this time.
- The sugar is extracted next. Even simple sugars are more molecularly complex than acids. As a result, water needs extra time and/or energy to completely dissolve them.
- Eventually, the water will begin to break down the plant fibers that hold the ground coffee together. Like all other plant structures including kale and celery, these fibers have a dry and bitter taste.
About 30% of the weight of any coffee bean is soluble. In that 30%, you have a variety of compounds that vary from sour, sweet, to bitter and acrid. The different ratio composition of these compounds in a coffee is what gives it its unique flavor. Most notably, during the extraction process, these compounds dissolve in a consistent order – from sour to sweet, to bitter.
The power of the extract
A cup of espresso is not only defined by the quality of its extraction; The “strength” of the drink is equally important. When we say “strength”, we do not mean the caffeine content. In coffee, strength (or ‘Strength’ in English) is also known as concentration and refers to the number of compounds dissolved in the drink.
A cup of filter coffee (drip coffee) has about 1-2% soluble matter in the cup; The remaining 98-99% is water. Espresso is a much more concentrated drink: it is made of 7-12% soluble compounds and 88-93% water.
The strength of a cup of coffee is largely a result of the ratio of ground coffee and brewed water. If you use too little water, your coffee will feel cloudy and too strong. If you add too much water, the coffee will feel thin and bland.
A regular cup of espresso will be six times stronger than filter coffee. It is also about six times smaller. So if you add enough water to make the volume six-fold. Then you can convert an espresso into something very close to filter coffee.
So the style of adding water to Espresso to form “ Americano ” (popular in the US) and “Long Black” (popular in Australia & New Zealand) has appeared in many coffee shops.
Finally, it is important to understand that strength is closely related to the extraction rate. If you are using less water to increase the strength of your coffee, it will be difficult for the water to extract all the desired flavors.
Therefore, we are always looking for an optimal brew ratio to create the fullness of the coffee we enjoy before embarking on improving the extraction process by adjusting the grinding method, and water temperature. , extraction (for Espresso) & pouring (for pour-over).
The strength of the coffee will also determine how easy it is to enjoy different flavors. The stronger the drink, the harder it is to separate the distinct flavors. Very small changes in concentration are easily discernible to our taste.
But at too high a concentration, no matter what type of coffee or how it is prepared. The coffee becomes very bitter and intolerable. Unfortunately, our tongues are not yet developed to accurately taste liquids in high concentrations.
So, you will only experience a bitter taste that is rough, overpowering, generic, and lacking in complexity. This bitterness is a natural physiological response of the taste buds to the high concentration of coffee extract square roots. And it disappears as the coffee is diluted daily word jumble.
There are a lot of issues here, but due to the necessary limitations of the article video, we will resist the urge to delve deeper into the brewing water, the phase ratio, the temperature of the brewing water & the efficiency of the process grind.
To further clarify coffee extraction, we also need to mention the concentrated plant extracts method, i.e. how the dissolution takes place: By diffusion or erosion, through immersion or filtration hide example sentences. ( percolation ), the effect of dilution, the role of the colloidal system in taste perception, etc…
These are just a few of the many factors that influence the coffee extraction process, which PrimeCoffee will continue to continue to post in the near future.
References:
- Primecoffea, Chiết xuất là gì?, Tháng Mười Hai 26, 2021