Guide · Automatic drip

Automatic drip coffee makers: what SCA certification tests, and the settings that matter

An SCA-certified home brewer has passed the lab tests in the Specialty Coffee Association’s Standard 310-2021: the slurry must hold 90–96 °C, the brew must reach 1.15–1.55% strength at 55 g of coffee per kilogram of water, and the grounds must extract evenly. Below: each test, what it leaves out, and the settings it assumes.

Updated 2026-10-16 · sources listed at the end · brands appear only where the SCA’s list or a cited source requires them; this lab has tested no brewer

What the standard covers

SCA Standard 310-2021, Home Coffee Brewers: Specifications and Test Methods (copyright 2022) applies to electric filter brewers for home use at atmospheric pressure. Manual pour-over drippers, French presses, espresso machines, pressurized brewers and pod machines are outside its scope. It grew out of the SCA’s earlier certification requirements for brewers.

The SCA’s equipment page says only machines fully evaluated at its third-party testing centre, ECBC.coffee, are considered. A pass leads to a three-year licence to use the SCA Certified mark, at a USD 5,000 annual fee paid by the maker. A 2019 SCA announcement placed testing at the UC Davis Coffee Center.

What certification tests

Test	Requirement in 310-2021	How it is measured
Basket volume	Holds the coffee for a full-capacity batch at 55 g/kg without overflowing as it swells	One full-capacity cycle, watched for overflow
Brewing temperature	Slurry at 90–96 °C (194–205 °F) once 33% of the water has been sprayed, and for the rest of the cycle	Three K-type thermocouples at the top centre of the bed, logged every second
Resulting brew	Strength 1.15–1.55% TDS at 55 g/kg at full capacity; brewers over 1 kg also at 1 kg	Coffee refractometer; grind may be adjusted within the limits below
Consistency	The temperature and brew results above, repeated	Three units, at least five full-capacity cycles each
Uniformity of extraction	Rating of 60 or more out of 100 (60 good, over 75 excellent, over 90 outstanding)	Spent bed dried 2 h at 103 °C; samples from three zones soaked in distilled water and their leftover soluble solids compared
Holding	If the carafe is heated: 80–85 °C (176–185 °F) for the first 30 minutes, never pushed above 85 °C by the element	Temperature read every minute for 30 minutes
Manual	A grind recommendation, a 55 g/kg ratio (or equivalent), a filter type and cleaning instructions; multi-setting brewers must name the setting that meets the target	Packaging, manual and linked online material reviewed

“Full capacity” is the maximum water capacity in the maker’s documentation. A liter of water weighs about a kilogram, so 55 g/kg is the SCA’s 55 g/L brewing reference: eight 5 fl oz coffeemaker cups (1,183 ml) take 65.1 g, as in how much coffee per cup. The slurry window matches the SCA’s 93.0 °C ± 3° recommendation for brewing water (see water temperature).

Reservoir (tested with water at 17 ± 3 °C).
One-way valve: stops water siphoning back.
Heating tube and element, with a thermostat against overheating.
Riser tube: thermosiphon pressure lifts the hot water.
Spray head.
Basket, filter and bed: slurry 90–96 °C from the 33% point.
Carafe: holds a full-capacity batch.
Warming plate: if heated, 80–85 °C for 30 minutes.

Drawn by pourxlab.com for this page from Wikipedia’s description of an automatic drip maker and SCA Standard 310-2021 (sources 13, 1). Generic schematic with no brand marks; layouts vary by model. Not to scale.

Test conditions

Coffee: arabica, medium roast (#55–#65 on the SCA/Agtron tiles), 1–1.5 weeks off roast; dark roasts for information only.
Water: 17 ± 3 °C; calcium hardness 50–175 ppm and alkalinity 40–70 ppm as CaCO₃, pH 6–8, no chlorine.
Room: altitude 0–300 m; everything at 20 ± 3 °C.
Filter: the maker’s; if none, Melitta papers for cones, Mr. Coffee for flat baskets.

Basket	Coarse limit	Target band	Fines limit
Cone	≤12% above 850 µm	≥68% at 425–850 µm	≤20% below 425 µm
Flat-bottom	≤17% above 1,168 µm	≥65% at 589–1,168 µm	≤18% below 589 µm

The text gives the flat band once as 589–1,198 µm; the table says 1,168. Shape matters on its own: in UC Davis tests with swappable baskets, tasters told flat-bottom from semi-conical brews apart but not medium from medium-fine grind (SCA 25 Magazine).

What it leaves out, and where sources disagree

No brew-time limit. 310-2021 sets none. Moccamaster’s 2023 blog says 4–8 minutes at full capacity, over 8 an immediate fail; Cosori’s 2026 blog also gives 4–8. Moccamaster adds sediment under 75 mg per 100 mL and up to 10 units × 10 cycles, which the 2021 text lacks. In 2014 Daily Coffee News listed brewing time among the criteria then used.
Temperature window. Batali, Ristenpart and Guinard (Scientific Reports, 2020) describe a 92–96 °C requirement, reached within the first minute; 310-2021 says 90–96 °C from the 33% point. In their study, drip brews at 87, 90 and 93 °C matched for strength and extraction showed no appreciable sensory difference.
“TDS” vs extraction. Moccamaster calls 18–22% a TDS target; in SCA terms that is extraction yield, while 310-2021’s strength target is 1.15–1.55% TDS (see the brewing control chart).
Not covered: part batches on brewers of 1 kg or less, dark roasts, altitudes above 300 m, taste panels.

Brewers on the SCA list

As read on the SCA equipment page on 2026-10-16, with its year labels. It is the SCA’s list, not a ranking.

Label	Entries	Brands as named
Certified 2026	17	Technivorm Moccamaster (8), Bonavita (5), Café / GE Cafe (2), Kismile (1), Cosori (1)
Certified 2025	5	Breville, OXO, Lotus Professional Series, Aarke, KRUPS USA
Certified 2024	3	Fellow, Zwilling, Braun
Certified 2023	3	OXO, Café Appliances, GE Profile

The SCA’s December 2025 “2025 Lineup” post also names an Aurora brewer by Strix (absent from the equipment page) and a GE Profile grind-and-brew model (labeled 2023 there).

Settings: brew the way the test does

Use the certified setting. A multi-mode brewer need comply in only one, and the manual must name it.
Weigh 55 g per liter of water: water (ml) × 0.055. A full 12-cup US carafe (1,775 ml) takes 97.6 g. Other strengths: the ratio calculator.
Grind medium. The NCA likens drip grind to kosher salt; start from the grind your manual recommends.
Use the filter the manual names, sized for the basket; the NCA warns a bunched filter can trap grounds and disrupt flow.
Fill with fresh, cold water, filtered if possible, not distilled or softened (NCA).
Brew a full batch when you can. Results are certified at full capacity (and 1 kg on larger brewers) only.
Drink within half an hour or decant. The plate test covers only 30 minutes.
Clean and descale. The NCA says rinse basket and carafe after each use and descale every 3–6 months, checking the manual before using vinegar.

Troubleshooting checklist

☐ Bitter: grind coarser (NCA).
☐ Flat or watery at the right dose: grind finer (NCA); see the grind size chart.
☐ Balanced but too strong or weak: change the ratio, not the grind.
☐ Basket overflows: a certified basket must hold a full batch at 55 g/kg, so check the dose and filter seating first, then try a coarser grind.
☐ Small batches taste different: use a small-batch mode if the manual lists one; otherwise brew closer to full capacity.
☐ Stewed taste after sitting: you are past the 30-minute holding window; brew less or decant into a thermal carafe.
☐ Papery taste: rinse paper filters before brewing (NCA).
☐ Slow brewing or white scale: descale (NCA).

Background

An automatic drip brewer heats only the water, which a thermosiphon lifts from the base to the spray head (Wikipedia). Wikipedia dates one of the first electric drip brewers, Gottlob Widmann’s Wigomat, to a 1954 German patent. Mr. Coffee came from Vincent Marotta and Samuel Glazer’s Cleveland company and former Westinghouse engineers Edmund Abel and Erwin Schulze; the Encyclopedia of Cleveland History dates first production to 1971, while Wikipedia says it reached home buyers in 1972 and spells the second name Edwin.

The SCAA renewed its brewer-certification cooperation with the European Coffee Brewing Centre in January 2014. Daily Coffee News says the Norwegian Coffee Association founded the ECBC in 1975; Wilfa gives 1971.