When we designed the Etkin Dripper, we started with SCA Ideal Cup Standards as defined by the Specialty Coffee Association’s Coffee Brewing Control Chart and worked backwards from there. Simply put, we wanted to make it easy to produce a great cup (or three) of coffee.
The Specialty Coffee Association is a non-profit trade association whose mission is to “Engage, inspire, and expand a sustainable global specialty coffee community through leadership in events, education, and research.”
Part of that research includes consumer preferences and best practices.
The SCA’s ideal cup standards are the nearly universally agreed upon parameters at which filter coffee tastes its best. Think of it as the bull’s eye in the center of a dartboard.
These consumer preferences were first discovered in the 1960s. Interestingly, the studies have been repeated over the decades and have produced similar results. Most coffee drinkers prefer a coffee that’s been brewed to a 18-22% extraction at a total dissolved solids (TDS) of 1.15-1.45.
But what does that standard mean and, more importantly, how can you achieve it? In order to answer that question we need to look at extraction and concentration.
Extraction, also called soluble yield, refers to the percentage of the coffee grounds that have been dissolved. Roughly 30% of roasted coffee is water soluble, but most coffee drinkers prefer extractions between 18-22%. Extract less than 18% and coffee tends to taste sour and vegetal. Too much of those delicious soluble compounds have been left in the coffee bed.
But if you extract more than 22% the coffee tends to be bitter and astringent. The telltale sign here is the dry mouthfeel that an over-extracted coffee leaves in your mouth.
Somewhere between 18-22% extraction is the sweet spot (pun intended) where most coffees taste their best.
The concentration, or strength, refers to how much of the finished brew is dissolved coffee solids (as compared to water).
Although extraction percentage preferences are practically universal, strength or concentration preferences are more subjective. For example, in Scandinavia, consumers prefer a more concentrated cup of coffee than in North America.
Bearing these regional differences in mind, most filter coffee drinkers prefer a cup of coffee that is between 1.15 and 1.45 TDS.
Personally, I can narrow down my own preferred range to 1.30-1.45 TDS. Amazingly one tenth of a percent can make a tremendous impact on the perceived strength and mouthfeel of a cup of coffee.
How Do You Make An SCA Ideal Cup Coffee?
To make coffee to SCA Ideal Cup standards, it helps to start with high quality ingredients: fresh roasted specialty coffee and filtered water. Ideally, your coffee should be roasted within a month of brewing and your water should have a total hardness between 40-175 ppm.
Just like baking a loaf of bread or mixing a cocktail, an ideal cup of coffee requires a correct recipe, usually expressed as a coffee-to-water ratio. The classic recipe here is 60 grams of coffee to 1 liter of water, which is a 1:16.667 ratio.
One liter of coffee is a little more than my wife and I can drink, so for my typical morning brew I use 45 g. of coffee and 750 g. of water. People who prefer a stronger cup can try a tighter ratio: 1:16 or even 1:15. Remember, reducing the amount of water you use (or increasing the amount of coffee you use) will lower your extraction percentage.
Once you know how much coffee and water to use, you need to make sure your grind size and water temperature are correct. For larger batches we tend to go for a medium-coarse grind size— around 800 microns. For water temperature, SCA standards are 92-96° C (195-205° F). If you don’t have a temperature-controlled kettle, you can simply bring your water to a boil then let it cool for 20-30 seconds.
If you start with the right amount of coffee (ground to the correct particle size) and the right amount of water (heated to the correct temperature), you’ve already done the heavy lifting. Most likely, your coffee is going to be pretty good. But the correct technique is also important. The best baristas spend years honing their technique, but I would start by focusing on the following:
- Blooming — At thee beginning of the brew, fully saturate the grounds and wait for 30 seconds as all of the carbon dioxide trapped in the grounds causes the coffee to “bloom.” The classic technique here is to use twice the amount of water as your dose, though personally I prefer to use 2.5-3 times the dose (i.e. for a 45 gram dose I might use as much as 125 grams of water to bloom).
- Pouring — I’m a firm believer in a spiral pouring technique and adding the water in increments, often called pulse brewing. The goal is to wet all of the grounds evenly. Take care to pour from the same height, so the water hits each part of the brew bed with the same velocity.
- Timing — Your total brew time for a one liter batch should be between 4-6 minutes. You can manipulate your brew time with your pouring technique, but if you’re struggling to get the brew into this window it might be an indicator that your grind size is incorrect.
It doesn’t take much to brew a good cup of coffee, but there are a few essentials:
- Grinder — The most important piece of coffee equipment you own is your grinder. Look for a burr grinder with steel or titanium burrs. Ceramic burrs can also work, but certainly avoid plastic. As a general rule, the larger the burr, the better the grind size uniformity.
- Kettle — Although not necessary, it helps to have a gooseneck kettle when making pour-over coffee. These days most electric gooseneck kettles come with temperature control.
- Scale — A scale will help you follow your recipe more accurately.
- Dripper — Finally, you need a pour-over dripper to hold the coffee.
Although I think you can brew a decent cup of coffee with practically any dripper, the best coffee drippers make it easier to brew a great cup of coffee.
The Etkin Dripper is designed with really deep ridges to hold the filter paper off the bottom of the dripper. This maximizes the effective filter area and helps minimize choking. This means more sweetness and less bitterness.
Practice Makes Perfect
At the end of the day, there’s no substitute for practice, hard work, and careful evaluation. You’ll likely discover that SCA Ideal Cup Standards are a fairly broad standard and that are meant to be a general guideline. Your personal preferences are probably more specific. Most importantly, remember that coffee is a beverage consumed purely for human enjoyment– so have fun!