indeed did the majority of coffee bean drinkers qualify the cup : “ If it ‘s black and potent, great ! ” The worlds most recognizable coffee bean stigmatize understand this and built an empire while ensuring that every cup of their chocolate was stronger and blacker than all others on the marketplace .
How did Starbucks achieve this ? That ‘s Lesson 008:100 – brew. This is not an article about Starbucks ( blue friends ) but rather about how blistering water turns black and transforms your consequence. This content will besides provide the model for dangerous coffee students concern in pursuing far learn into Extraction Science, SCA Certifications and more .
INTRODUCTION TO COFFEE
- What is coffee? Coffee is a fruit that grows on a small tree. We identify the two main species as Arabica and Robusta. The fruit and growing conditions of both differ dramatically.
- Coffee as a commodity travels further and goes through more changes than many other agricultural goods. After coffee cherries are picked, two symmetric seeds (beans) are extracted from the fruit, dried and then eventually roasted to be brewed. It is a long process to getting coffee from distant equatorial mountain farms to the final drink served in downtown London, Seattle, or Melbourne.
BREWING GUIDELINES – STRENGTH & EXTRACTION
- There is a great misconception in the normal world of coffee (where 99.9% of the world lives), but first we should define the difference between strength and extraction.
- Strength is the concentration of coffee in the cup, whereas Extractions is the amount of soluble coffee matter dissolved from the bean/grounds. Think of this as as glass of water and a lemon. Extraction = the process of squeezing that lemon so that 2 Tbsp (30g) of lemon juice drips into my glass. Strength = the amount of water (concentration) used to mix with that lemon juice. If I add 1 cup (236g) of water then the concentration of lemon is 11% or 30/266. Hang with me here. If I add 4 cups of water (944g) then I have weakened the drink, made it less strong (a.k.a. less concentrated) to about 3% lemon water.
- The same logic applies to Starbucks as said earlier. While most gas station coffee were using more water and less coffee, they used more coffee to brew your cup of black coffee a bit stronger. This is Strength.
- What about Extraction? Pouring hot water through a bed of coffee in a filter makes the coffee dissolve. That’s like squeezing our lemon. Starbucks did NOT grind coffee more fine (i.e. squeeze the lemon harder so that more comes out)… they simply used more coffee grounds (i.e. used 2 lemons instead of one). This is essential as we will learn more about extraction parameters and their effect on your cup of coffee.
WATER TO COFFEE RATIO
- A sufficient amount of ground coffee is required, per liter of water, to make a decent tasting cup of coffee. This is defined as the Golden Cup standard: 50-60 grams of coffee per liter (1,000g) of water. The “Golden Cup” was a simple statistical sampling of various brewing ratios 1:14 1:15 – 1:16 – 1:17 – 1:18 – 1:19 – 1:20 where respondents said they preferred more or less strong coffee.
- Specialty coffee students understand very clearly how increasing or decreasing that ratio leads to incredible taste and sensory impacts on the coffee brewed. This is because as coffee dissolves into hot water many good, sweet, aromatic compounds come out in phase 1 and 2 while other less desirable compounds dissolve in stages 3 and 4.
- The ratio of coffee to water commonly used to make a single espresso is between 1:2 – 1:4 while the ratio of coffee to water commonly used to brew (decent) coffee is between 1:15 – 1:18.
- A single shot of espresso then requires 7 – 10g of ground coffee for a 20-30ml (1 ounce) beverage. At the same time a brewed cup of coffee requires 15-18g of ground coffee for a 250ml beverage (think small/medium cup). As you see the numbers above it’s very easy to understand why so many people have the idea that espresso is too strong… because it is so concentrated! It’s like eating that lemon, rather than squeezing it’s juice into a glass of water.
- Grind size affects the rate of extraction based on the surface area of coffee molecules. Additionally the speed that water water flows through the coffee bed has a great impact in brewing. Think of sugar granules you wish to dissolve in a cup of water. Those finely ground will dissolve faster/easier than the large sugar crystals.
- Baristas and brewers then must determine the appropriate grind texture for espresso, paper filter drip coffee and more coarse ground methods such as the French Press. Grind size is determined by the brewing device – not by your choice of coffee flavor. This is helpful as an anchor – too many people think changing your grind is the key to stronger coffee (wrong).
- The time the water is in contact with the coffee is mainly a function of grind size. This means a powdery fine ground espresso needs to only be in contact with hot water 24-30 seconds whereas a coarse ground French Press soaks for 4-5 minutes to ensure coffee extraction occurs.
- The amount of time the water is in contact with the coffee enables coffee solids to be dissolved into the beverage. This results in different brew times for different brew methods and brew volumes.
- For example a filter brewed coffee of 1ltr (32oz) should occur in 4-6 minutes; a single cup filter brew in 2-3 minutes; an espresso 22-30 seconds.
- If brew time goes long (water moves too slowly through coffee bed) then over-extraction occurs. This is pulling too much soluble matter from the coffee into the brewed beverage. The inverse is true if time becomes too short: under-extraction.
- The correct water temperature is required to dissolve the desired flavors from the ground coffee. This range is 92 – 96C (195 – 250F). The same direct relationship as brew time occurs with water temperatures. Water too hot = over-extraction. Water too cool = under-extraction.
- An increase in turbulence of the water in contact with the coffee will increase extraction. The same direct relationship with water and time holds true: too much turbulence = over-extraction; too little turbulence = under-extraction.
- It should be noted that like grind size, turbulence is determined according to the brewing methods. French presses allow coffee to soak immersed in water; while a filter brew has a flowing water contact; while an Aeropress or Syphon Pot require you to manually stir the coffee and water for a period of time.
- Water quality varies in different regions and this can affect brew quality and machine function. High and low ph affect coffee flavors. Water mineral content (ppm) affect the amount of soluble coffee matter that can be dissolved (suspended) in water. Additionally these ph and ppm measure can cause build up or deterioration in machine pumps and water heaters.
- You should be able to demonstrate an understanding of the existence of hard and soft water and limescale as it affects unwanted taints/odors or extraction issues in coffee.
- Different filtering methods are used according the brewing device such as: paper, cloth, espresso basket, metal filters. Each of these filtrations have an impact on the final beverage and impressions provided by brewed coffee. Proper cleaning and storage are essential for long-term happy usage of each.
- Like temperature and time, the relationship between pressure brewing and pressure use is direct. Mocha pots, espresso machinese, Areopress, syphon and other hybrid methods introduce pressure as an extraction variable. Typically this pressure is fixed by the device or machine. Grind size and brew time correlate in turn.
- A good barista should be able to describe the impact of an increase/decrease in pressure on the rate of extraction.
- Coffee freshness, storage and preservation are managed by controlling environmental: temperatures, moisture, oxygen and light.
- You should be able to explains the factors that adversely affect coffee freshness such as leaving bags open, pre-grinding coffee, keeping beans in the refrigerator, etc.
- Cleaning (or not cleaning) brewing equipment has a direct impact on the taste of coffee. Coffee contains oil which becomes rancid over time. Additionally some brewing devices are more prone to having old coffee grounds become clogged or accumulate for undesirable flavor impacts.
- You will notice that many restaurants, gas stations and convenient coffee locations serve old – heated coffee. This causes the breakdown of coffee aromas and taste over time, caused by the loss of temperature, reheating and/or evaporation. Additionally acids become corrupted and harsh while pleasant volatile aromas dissipate.
- A good barista can taste and discuss differences in brews that have been held under varying conditions and times in a blind coffee tasting.
BREWING METHODS AND EQUIPMENT
- Mentioned earlier with brewing impacts were various families of brewing methods: Immersion, Gravity, Pressure, and Hybrid.
- A great barista can demonstrate the correct use of each method of brewing using the correct grind profile and brewing recipe to produce a Golden Cup Standard Coffee.
We diverged a bit from our initial Starbucks theme in decree to hit the major points of Brewing and Extraction required by SCA.Training. however, you ‘ll understand immediately that Starbucks offered an supernumerary potent ( higher coffee : water ratio ) brew while only featuring phase 1 and 2 in their extraction ( the first better flavors ) by adding more coffee to their trickle baskets than say McD ‘s or the Gas Station. even with a extremely black roast ( like SBUX ) you can focus on only those chocolatey / burned sugar flavors which hold up impregnable in lattes and milk. Well done Starbucks and thanks for showing us how to manipulate coffee bean concentration and origin to capture a global fanbase .
That was our first bass dive into BREWING as lesson 008:100. This will pave the way for future deep-dives into the art of chocolate brew to help you appreciate and grow in coffee bean. If you who would like to master these skills and even get certified through training and exams reach out and let me know. Welcome to the Coffee Crew ! If you found this helpful please share, give a like and gossip so that friends can find it .
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