A second boy on the way, a company on the way out, a capsule machine humming on the counter, and a hand grinder in a hallway at five in the morning because the electric one wakes the house. Where the money should go, and why.
It is five in the morning in July and already light, the pale, washed light of a Colorado summer before the heat arrives, and I am grinding coffee by hand in the hallway with the door shut, because the electric grinder wakes everybody, and this is how I found out that the hand grinder was the better machine all along.
There are thirty seconds of resistance in the wrist, and a sound like gravel under a boot or like the old dial-up modem finding its voice, and a smell that arrives before I have done anything else at all, dark and sweet like a bakery at closing time, and under all of it, every morning, the memory of the first grinder I ever heard. It was in my grandmother's kitchen in Tamluk, and it was made of stone: the shil, a flat grey slab on the floor, and the nora, a stone roller she rocked across it with both palms, so that the kitchen filled with a slow rumble like a train crossing a far bridge at night, and the mustard seeds became a yellow paste that stung the nose, and the turmeric left a stain on the stone that no scrubbing ever lifted. She said mustard turns bitter if you grind it too long or too hard, and she added a green chilli and a pinch of salt to keep it sweet, and I understand now, half a world away, that she was controlling extraction with her wrists long before anybody taught me the word.
Everybody, this summer, means my son, who is nearly four and sleeps like a starfish, and my wife, who is carrying our second boy, due in November, and sleeping badly in the heat. I am happier about the baby than I have been about anything, and I know now that the tiredness passes, and meanwhile Plexflo, the company I build on a screen at night with a small team in Bengaluru, is unwell, and I keep feeding it my own money, because we are so close, and because I have already fed it so much that stopping would feel like admitting the first money was wasted. I know the name of this mistake well enough to teach it, and next month we will spend more than we should on a trade show in Houston that I am about ninety percent sure will change nothing, and we will go anyway. My wife was going to begin a business degree this autumn, and with the baby coming she has withdrawn. I believe a house runs on roles, a mother's and a father's among them, and that the responsibilities those roles carry weigh more than any quarrel over whether they are equal, and we have taken ours up with our eyes open: hers, this year, to carry the boy and let the degree wait for a kinder autumn, and mine, the one my father carried in Howrah and his father in Tamluk, to hold the roof up, which is exactly the duty I betray a little every time I wire another month of our savings into a company that has not yet earned it.
There is also, since March, a capsule machine on the counter, which I wrote about with some shame and which makes the second cup at my desk with a whirr like a small drone, while the hand grinder makes the first and stays the one part of this restless summer that does exactly what I ask of it.
The question I am asked most often is where, with a certain sum to spend on coffee equipment, the money should go, and the answer is the grinder, every time, by a margin so wide that I will argue it with anyone.
Why the grind is the master variable
I wrote in the note on extraction that one idea governs coffee, which is how much of the bean dissolves into the cup, and that three dials move it, and of those three, grind size is the biggest by a distance you could measure in miles.
Extraction speed against particle size, as a rule of thumb. Surface area grows faster than the particle shrinks, which is why grind is the biggest dial you have.
Surface area governs how fast water pulls things out of coffee, and surface area grows faster than the particle shrinks, the way a sheet of paper torn into confetti has far more edge than the sheet ever had, so that when you halve the size of the pieces, extraction runs roughly four times as fast, and every other dial moves the same outcome by less.
There is a second, quieter reason, which is that ground coffee goes stale within minutes, all surface and all exposed and oxidising like a cut apple browning on the counter, and so grinding fresh, just before you brew, is by itself a bigger improvement than any brewer you could buy, and the grinder hands you both gifts at once.
Blade or burr
A blade grinder smashes beans the way a blender smashes ice, producing powder and boulders in the same batch with a noise like a coin in a washing machine, and the powder over-extracts while the boulders under-extract, so the cup is sour and bitter at once, permanently, whatever else you do.
The writer whose book I keep beside the kettle has the best picture of this: boil a quail's egg and a hen's egg and an ostrich egg in the same pan for three minutes, and something will always be wrong.
A burr grinder crushes the beans between two hard surfaces set a fixed distance apart, so the pieces come out close to one size, like sand from a sieve, and that is the difference that matters.
Find your starting grind
Burrs, and what actually differs
Conical burrs are a cone turning inside a toothed ring, where big teeth break the bean and finer teeth further down slice and crunch it, and they are forgiving, and they make a little more fine dust, and they give more body, which is to say more of the oils and the weight I want in a cup.
Flat burrs are two rings facing each other, and the beans are flung outward through the gap between them in something closer to a nibble than a chew, which gives cleaner separation and more clarity in the cup and usually leaves more coffee stranded inside the machine; a flat burr, when I think about it, is my grandmother's shil and nora stood on edge and set spinning, two hard faces and a narrow gap and a seed with nowhere else to go.
The geometry also changes how fine your adjustment is: on flat burrs, moving the burr a small distance changes the gap by that same distance, and on a cone the same movement changes the gap by less, because the faces are angled, so a conical grinder gives you finer control for each click of the dial, the way a long lever gives finer control than a short one, which is worth knowing for anyone grinding in a hallway in the half-dark.
Steel burrs and ceramic burrs both dull eventually, like kitchen knives, and replacing a worn set improves a cup more than most people expect. On hand grinders, the single largest difference in daily life at any price is whether the adjustment sits on the outside or the inside, and outside means you can switch from filter to espresso and back and keep your place, like a bookmark.
Fines and boulders
Coffee is brittle, like a biscuit, and however good the grinder, some of it shatters into dust, and most grinders make about a tenth of their output as these fines, which over-extract and clog paper and make sludge in a press and wreck the flow of an espresso, while at the other end the oversized rubble under-extracts. Uniformity is the whole game, and the reason a commercial grinder can cost as much as a small car is that it makes fewer fines and less rubble than anything else.
Two pieces of real science you can use this morning
I read papers for a living, and two pieces of physics have changed how I grind.
The first is a paper from a few years ago that measured how the particle sizes of ground coffee change with the temperature of the bean, and found that neither the origin of the coffee nor its processing changed much while the temperature changed a great deal: colder beans shatter into a narrower, finer range of sizes, the way cold chocolate snaps clean and warm chocolate smears, and the biggest change happens between room temperature and the freezer. This is the scientific basis for freezing your beans, and I keep single portions in small sealed jars in the freezer now, next to the peas, and grind them straight from cold, and the note on freshness says why that helps twice.
The second is closer to my own trade, because it is electricity: breaking a brittle solid moves charge from one fragment to the next, the same physics that throws lightning through the ash above an erupting volcano, and the static makes the grounds clump and cling inside the grinder like a balloon rubbed on a jumper. Water lets charge leak away, which is why the clinging is worst in a dry Colorado winter, and home baristas have been passing around the trick of a few drops of water on the beans before grinding, and I suspect that one day somebody who studies lightning in volcanoes will measure what that drop does to an espresso and find it stronger and more even. I put one drop on the beans with a fingertip every morning now, and the grounds fall from the chute as meekly as sand in an hourglass.
The words for grind size do not travel
There is no universal scale, and two identical grinders from the same factory differ slightly, so anyone who tells you to grind at eighteen clicks is describing their own machine, the way a friend's directions only work if you set out from their house, and words and a notebook will serve you better.
Grind
What it looks like
What it is for
Finest, just before it clogs
Flour
Turkish coffee
Fine, clumps a little
Fine sand
Espresso
Fine-medium
Between the two above
Moka pot, cloth filter
Medium
Caster sugar
Pour-over with paper
Medium-coarse
Granulated sugar
Slower pour-overs, the Clever
Coarse
Sea salt flakes
French press, immersion
Very coarse
Rock salt
Long steeps, cold brew
Start in the middle of the range for whatever you brew.
Taste, then move one step.
Sour: go finer.
Bitter: go coarser.
Write it down, as the brewing note keeps asking you to.
What to actually buy
Prices move, and this is one particular summer, so read what follows as the outline of a shelf with the names left blank.
A good hand grinder with steel burrs, at the price of a few bags of coffee, is the best value in the whole of coffee equipment, and I would rank it above anything else on the shelf. In India there is one obvious choice at that level, and a step up buys smoother bearings and the adjustment on the outside, and the top of the hand-grinder range, at a few times the price, competes with electric grinders costing far more, and there is one model made only for filter coffee that produces fewer fines than anything I have used.
For electric grinders there is one honest default for filter coffee that has held that place for a decade, and a version of it for espresso, and a more expensive flat-burr model for people who want maximum clarity and brew only filter; I am not one of those people, because clarity is a fine thing and I would still rather have the body and the oils of a dark roast that coats the tongue like warm ghee.
List prices for two common electric grinders, with the Indian price converted to dollars. The gap is import duty and a thin market, and it changes with the exchange rate.
When I priced the same grinders in India, the electric ones carried a heavy premium, and several of the best-known brands were not sold there at all through any retailer I could find, while the hand grinders, lighter and simpler to ship, suffered less. If you are buying in India, this tilts the decision even further toward a hand grinder, which was already the right answer and which, in a country that has ground its masala on stone for millennia, feels like a homecoming.
Maintenance that nobody does
Every few kilos of coffee: cleaning pellets through the burrs, or a handful of rice if the maker allows it, until the sound changes from gravel to something cleaner.
After every change of setting: grind a few grams and throw them away, because the path from the burrs to the spout holds the old grounds, and the first cup after an adjustment is a lie.
The hallway
By any sensible accounting the hallway is a small hardship at five in the morning, and yet it is thirty seconds in which I use my hands and my nose and nothing else, with no screen and no invoice and no decision about a company whose answer I already know, and I wonder now whether my grandmother's hour at the stone, the rocking and the rumble and the yellow on her fingertips, was the one part of her day that belonged to her alone. My wife is asleep behind one door and my son behind another, and in a few months there will be a third door, and I will still be out here, turning a handle, and if I had to give up every other part of the ritual, this is the part I would keep.
One thing to do this morning:
Open your grinder and look: blades or burrs.
Blades: your next purchase is a burr grinder, and all other equipment advice can wait.
Why is the grinder more important than the brewer?
Because grind size is the biggest dial you have. Halving the particle size roughly quadruples how fast coffee extracts. A cheap brewer with a good grinder makes better coffee than an expensive brewer with a blade grinder.
Is a hand grinder good enough?
Yes. A steel-burr hand grinder in the range of five to ten thousand rupees, or about a hundred dollars, makes coffee that rivals electric grinders costing several times more. It takes about thirty seconds of turning for one cup.
Should I freeze coffee beans?
You can, in sealed single portions, and grinding them from frozen gives a more even grind. Research in 2016 found colder beans shatter into a narrower range of particle sizes. Do not open and refreeze the same container repeatedly.
