Sarah Chen
Senior Coffee Reviewer & Grinder Specialist
Q Grader Certified (CQI) | SCA Certified
About Sarah Chen
Sarah Chen's coffee career started in the cupping labs of San Francisco's Blue Bottle Coffee, where she spent four years as a quality-control cupper before earning her Q Grader licence from the Coffee Quality Institute in 2014 — a certification that requires passing 22 separate sensory and technical exams. That process gave her a structured, repeatable framework for evaluating flavour, consistency, and equipment performance, one she has applied to every review she has written since.
Specialising in grinder technology, Sarah has personally tested more than 100 burr grinders across consumer and prosumer categories, measuring particle-size distribution with a Kruve Sifter Pro and comparing grind uniformity using a calibrated digital micrometer. She has consulted for specialty coffee shops in the San Francisco Bay Area on equipment selection and has contributed grinder methodology pieces to Roast Magazine and Perfect Daily Grind.
Sarah joined The Coffee Locator in 2018 as Senior Reviewer. She holds SCA certification across the Brewing and Sensory modules and applies a structured 25-point grinder scoring rubric — covering burr geometry, static, retention, grind uniformity, and stepless adjustment range — to every grinder she evaluates. Her work is peer-reviewed by Michael Anderson before publication.
"Grinders are underrated. Most people obsess over the machine, but 70% of shot quality lives in the grinder. I test grinders the way a lab scientist would — with consistent inputs, measured outputs, and no emotional attachment to brand reputation. Numbers don't lie."
Professional Certifications
- Q Grader Licence — Coffee Quality Institute (2014)
- SCA Coffee Skills Programme — Brewing & Sensory modules (2016)
- Certified Cupping Judge — Specialty Coffee Association
Key Achievements
- Passed all 22 Q Grader exams — Coffee Quality Institute (2014)
- Personally tested 100+ coffee grinders with particle-distribution analysis
- Published grinder methodology in Roast Magazine and Perfect Daily Grind
- Consulted for specialty coffee shops in the San Francisco Bay Area
- 12+ years of formal specialty coffee cupping and sensory evaluation
Career Timeline
- 1
Quality Control Cupper
Blue Bottle Coffee, San Francisco CA
Conducted daily production cuppings; developed tasting vocabulary and sensory calibration across single-origins and blends.
- 2
Q Grader Certification
Coffee Quality Institute
Passed all 22 Q Grader examinations including olfactory, triangulation, grading, and roast identification modules.
- 3
Equipment Consultant
Independent — San Francisco Bay Area
Began advising specialty cafés on grinder and brewer selection; developed first structured grinder scoring rubric.
- 4
SCA Certified — Brewing & Sensory
Specialty Coffee Association
Completed SCA Coffee Skills Programme Brewing and Sensory modules.
- 5
Senior Coffee Reviewer
The Coffee Locator
Joined as lead grinder specialist; expanded methodology to 25-point grinder scoring rubric using Kruve particle-size analysis.
- 6
Contributing Writer
Roast Magazine & Perfect Daily Grind
Published peer-reviewed grinder methodology pieces reaching a combined audience of 400,000+ coffee professionals.
Testing Methodology
Each grinder is tested over a minimum of 30 days with at least 5 kg of coffee across three grind-size ranges (filter, espresso, and coarse/pour-over). Static retention is measured by weighing the hopper before and after each grind cycle. Particle distribution is analysed with a Kruve Sifter Pro using a six-sieve stack. Grind uniformity scores are derived from the bi-modal ratio — the proportion of fines vs boulders relative to the target sieve size. All results are recorded in a standardised spreadsheet and averaged across three separate test dates before a score is assigned.
Testing Equipment Used
- Kruve Sifter Pro — particle-size distribution analysis
- Digital micrometer — burr gap calibration verification
- Acaia Pearl scale — 0.1 g resolution for retention measurement
- VST Refractometer — extraction yield for grind-comparative brew tests
- EK43 reference grinder — baseline uniformity benchmark
- Still Air Box — static charge measurement environment
Published In
- ›Roast Magazine — "A Measurable Framework for Evaluating Burr Grinders"
- ›Perfect Daily Grind — "Particle Distribution: What It Means for Home Brewers"
- ›The Coffee Locator — Lead reviewer, 100+ grinder evaluations
Consulted For
- ›Sightglass Coffee, San Francisco CA
- ›Ritual Coffee Roasters, San Francisco CA
- ›Verve Coffee Roasters, Santa Cruz CA
- ›Multiple independent specialty cafés across the Bay Area
Guides by Sarah Chen(34)
7 Alternative Espresso Drinks to Try
Discover the incredible variety beyond your usual order—from bold cortados to indulgent mochas
Read the guideCoffee EducationAmericano vs Espresso: Key Differences
Is an Americano just watered-down espresso? We explain the real differences in taste, strength, caffeine, and when to choose each drink
Read the guideGrinder GuidesBurr vs Blade Grinder: Which Is Better?
After testing over 100 grinders, here's the honest answer on whether a burr grinder is worth it — and at what budget it pays off
Read the guideCoffee EducationCoffee Drink Differences Guide
Master every espresso drink from latte to macchiato and navigate café menus with confidence
Read the guideMaintenance GuidesCoffee Maker Leaking: Causes & Fixes
Dripping from the bottom, overflowing the filter basket, or weeping from the carafe seal — here is exactly why it is happening and the fix for each cause
Read the guideCoffee EducationCoffee Roast Levels Chart & Flavors
A plain-English chart of light, medium, and dark roast coffee — what each one actually tastes like, how it's made, and which roast fits your brew method.
Read the guideBrewing GuidesDrip vs Pour Over Coffee: Expert Guide
Bloom timing, water temperature, grind control — and which method actually wins for flavor
Read the guideCoffee EducationFlat White vs Cappuccino vs Cortado
Expert breakdown of three espresso classics—ratios, foam, technique, and taste
Read the guideGrinder GuidesHow to Choose a Burr Grinder (2026)
Expert guidance for selecting the perfect burr grinder for your brewing style and budget
Read the guideBrewing GuidesCold Brew Recipe: 1:8 Ratio (2026)
The complete cold brew ratio, steep time, and filtering method — including why 18 hours beats 24, and when concentrate beats ready-to-drink
Read the guideBuying GuidesHow to Pick Espresso Beans (2026)
Expert guidance for selecting the perfect espresso beans for your taste and brewing style
Read the guideBrewing GuidesHow to Use a Moka Pot (Step-by-Step)
Grind size, water temperature, heat control, and the exact moments that separate a bitter stovetop espresso from a genuinely great cup
Read the guideCoffee EducationLatte vs Cortado: Key Differences
Expert breakdown of strength, flavor intensity, and caffeine content
Read the guideCoffee EducationMacchiato vs Latte: The Difference
Expert breakdown of these two Italian espresso classics—from ratios to technique to taste
Read the guideGrinder GuidesManual vs Electric Grinders (2026)
Discover which grinder type matches your brewing style, budget, and lifestyle
Read the guideCoffee EducationWhat Is a Cortado? Cortado vs Latte
The complete barista guide to the cortado coffee drink — origin, 1:1 ratio, glassware, recipe, and how it compares to a flat white or latte
Read the guideCoffee EducationFlat White vs Latte: The Difference
The barista's guide to the flat white — milk ratio, microfoam technique, flat white origin, flat white size, and how it compares to a latte and cappuccino
Read the guideEspresso GuidesWhat Is a Lungo? The Long Espresso Shot
Same dose, more water — lungo vs espresso, lungo vs americano, brew ratio, caffeine, and when the long shot actually makes sense
Read the guideEspresso GuidesWhat Is a Ristretto? Espresso Guide
Same dose, half the water — ristretto vs espresso, why it tastes sweeter, and the one grind adjustment that makes or breaks it
Read the guideCoffee EducationWhat Is a Cappuccino? Espresso Guide
The exact 1:1:1 ratio, the dry vs wet distinction, Italian tradition, and why most café cappuccinos miss the mark — explained by a former barista trainer
Read the guideCoffee EducationWhat Is Coffee Bloom? Explained
Why those 30 seconds at the start of your brew matter more than most people realise — and how the bloom connects directly to freshness, extraction, and flavour
Read the guideEspresso GuidesWhat Is Espresso Crema? (2026)
The golden foam on your espresso shot — what it is, why it forms, what good crema really looks like, and the honest answer on whether it matters for taste
Read the guideEspresso GuidesWhat Is Espresso? Expert Barista Guide
From grind size and 9-bar pressure to crema, extraction ratios, and tamping — a plain-English walkthrough of what espresso actually is, and everything you need to pull great shots at home.
Read the guideCoffee EducationWhat Is a Moka Pot? Complete Guide 2026
The stovetop espresso maker demystified — a clear explanation of exactly what a moka pot is, how it really works, and why it's not quite the same as espresso
Read the guideBrewing GuidesPour Over Coffee: Complete Guide 2026
From bloom to final sip — a former barista trainer explains the pour over method, grind size, water temperature, and how to dial in your best cup
Read the guideEspresso GuidesWhy Does My Coffee Taste Bitter? (Causes & Fixes)
Bitter coffee is one of the most common home-brewing complaints, and it nearly always traces back to the same five root causes.
Read the guideGrinder GuidesCoffee Grind Size Chart: Expert Guide
Espresso, French press, pour over, cold brew, AeroPress — exact grind sizes, micron ranges, and calibration steps for every method. No dial numbers. Just results.
Read the guideBrewing GuidesHow to Make a Latte at Home (2026)
The exact ratio, milk steaming technique, and pour method — everything you need to make a café-quality latte at home
Read the guideBrewing GuidesHow to Make an Americano (2026)
The correct ratio, pour order, and the small details that turn a diluted espresso into a genuinely excellent cup.
Read the guideBrewing GuidesHow to Make an Iced Latte (2026)
Espresso over ice with cold milk — the right ratio, the right pour order, and how to avoid the watered-down version.
Read the guideCoffee EducationWhat Is Single-Origin Coffee? Explained
Learn what single-origin means, how it differs from blends, and why traceability matters for flavor
Read the guideCoffee EducationWhat Is Specialty Coffee? SCA Grades
Understand the SCA scoring system, 80+ point grading, and what separates specialty from commodity coffee
Read the guideEspresso GuidesWhat Is a Doppio? Espresso Guide
Why the doppio became the default espresso, how it differs from a single, and what it means for every drink on the café menu — explained by a former barista trainer
Read the guideCoffee EducationWhat Is a Macchiato? Complete Guide
Two drinks, one name — traditional espresso macchiato vs latte macchiato explained: ratios, taste, glassware, and which to order
Read the guideProduct Reviews by Sarah Chen(31)
Blue Bottle Coffee Three Africas Review
A fruit-forward, third-wave roast that shines in pour-over and rewards a dialed-in espresso setup — not a beginner-friendly dark roast.
illy Classico Review
A smooth, balanced 100% Arabica blend with caramel and chocolate notes — best enjoyed as straight espresso rather than buried in milk.
Intelligentsia Black Cat Classic Review
An approachable specialty-grade espresso blend with milk chocolate and dried cherry notes, consistent enough for daily milk drinks.
Lavazza Super Crema Review
A forgiving, classic Italian-style espresso blend that builds reliable crema and performs especially well in flat whites and cappuccinos.
Onyx Coffee Lab Geometry Review
An award-winning medium-light blend with dark chocolate and dried stone fruit complexity — versatile across espresso and pour-over alike.
Peet's Coffee Dark Roast Whole Bean Review
A bold, chocolatey dark roast with no sourness, well suited to French press, lattes, and entry-level espresso machines.
Stumptown Holler Mountain Review
A Pacific Northwest-style dark roast with a bold, chocolatey body that holds up well across espresso, Americanos, and French press.
aarke Coffee Maker Review
A clean, Scandinavian-designed drip maker with honest SCA-range brew temps and a built-in bloom cycle.
BALMUDA The Brew Review
A design-forward automatic brewer using swing-arm tech to mimic pour-over — best for smaller households with a grinder on hand.
Fellow Aiden Review
A precision brewer with app-controlled bloom, flow, and temperature per recipe — for enthusiasts who rotate coffees.
Keurig Smart Brewer Review
A Wi-Fi-connected single-serve machine built for busy, multi-person households wanting app-scheduled brews over extraction precision.
Miele CM 5310 Silence Review
A notably quiet bean-to-cup super-automatic making fresh-ground espresso drinks at the push of a button.
Mr. Coffee 14-Cup Programmable Coffee Maker Stainless Steel Review
An affordable, large-batch programmable drip maker built for fast wake-up brewing rather than precise extraction.
Outin Mino Review
A pocket-sized portable espresso maker for travelers and campers who want real coffee on the go, charging via USB-C in minutes.
OXO Good Grips Cold Brew Coffee Maker 32 oz Review
A tap-release cold brew system that delivers cleaner concentrate than a basic pitcher, without the mess of straining by hand.
VINCI Express Cold Brew Coffee Maker Review
An on-demand cold brew maker for anyone who wants concentrate without planning an 18-hour steep in advance.
1Zpresso K-Ultra Manual Coffee Grinder Review
A manual grinder with 8-micron adjustment precision that handles both espresso dialing and filter coffee equally well.
Baratza Encore ESP Review
An electric grinder with stepless micro-adjustment under $250 and Baratza's repair-friendly design, spanning espresso through French press.
Baratza Virtuoso+ Review
A filter-first electric grinder with solid espresso capability, a large hopper, and a digital dosing timer for household use.
Breville Smart Grinder Pro Review
A versatile electric grinder for both espresso and filter coffee, with a Dosing IQ feature for consistent shot-to-shot repeatability.
Capresso Infinity Plus Conical Burr Grinder Review
An affordable conical burr grinder for drip and French press drinkers stepping up from a blade grinder, under $110.
Comandante C40 Review
A premium hand grinder with Nitro Blade burrs delivering lab-grade precision for pour-over and filter coffee.
Turin DF64 Gen 2 Review
An electric grinder with factory-aligned 64mm flat burrs and sub-0.2g retention, built for single-dose espresso workflows.
Eureka Mignon Specialita Review
A notably quiet 55dB Italian flat-burr grinder with commercial-grade durability, built for daily espresso use.
Fellow Ode Gen 2 Review
A single-dose grinder built specifically for pour-over and filter coffee enthusiasts — not intended for espresso.
Fellow Opus Review
A well-rounded electric grinder spanning espresso to French press, with working anti-static tech at a competitive price.
Hamilton Beach Fresh Grind Electric Coffee Grinder Review
A basic, budget electric grinder for casual drip coffee drinkers wanting fresher grounds without much upfront cost.
KINGrinder K6 Review
A high-capacity manual grinder with 48mm titanium-coated burrs, well suited to batch-brewing filter coffee for two or more.
Mavo Phantox Pro Review
A stepless manual grinder with titanium burrs and infinite micro-adjustment, built for filter-focused precision brewing.
Timemore Chestnut C3 Review
A portable, all-metal manual grinder built for travel and manual brewing rather than daily espresso use.
Turin DF64 V5 Review
An electric grinder built for true single-dose espresso workflow, with sub-0.2g retention and exceptional grind quality.