A coder’s guide to coffee (2002) | Hacker News Reader

A coder’s guide to coffee (2002)

blog.moertel.com

41 pointsTomte61 comments

> Buy only whole-bean coffee roasted within the last few days

Ah, but can you actually taste this? (Holding all other variables constant, and grinding the beans before brewing either way.)

My friend Jerry and I are working on a series of articles on Triangle Tests that we've been doing. As it happens, we did this exact test at Google with 14 volunteers, testing whether people could tell the difference between beans roasted within the last day vs. beans two weeks off roast.

Spoiler: no, they can't. In a Triangle Test, you have three samples, two the same and one different. You have to pick the one that's different.

Caveat: maybe you can tell. If you can, that's all that matters to you. I can tell coffee made with a bamboo coffee filter from the same made with paper, so I don't really care if the general population can.

I'd put up the video, but Jerry did one with faces blurred and I don't remember where that is, at the moment. I'll put it up when I get it.

Edit: here's the video. https://www.youtube.com/watch?v=LyjQAvFs6w0

I think 2 weeks off roast is close enough to 'fresh' that the difference is going to be subtle. I'd love to see an experiment like this with 3-day old vs 2-months old. I'd guess most people could tell in that case.

And maybe then bring that two months in and see where the cutoff is that people can/can't tell. I'll guess it would be 3-4 weeks or so for most subjects.

I've never heard of a "triangle test" before but I like that format!

Yes. 1/3 chance of being right randomly. So even 3 right answers is 1/27, which is below the p = 0.05 threshold commonly used.

Not an expert by any means, but given personal experience: By taste it feels fairly obvious when the roast is over 3-4 weeks old. And it's not only perceptible by taste, it is fairly difficult to ignore while blooming a pourover when it's fresh but specially so during calibration for espresso: when a grind is on its first week it's much harder to find the right spot, and when it's over ~3 you're clearly grinding noticeably finer.

Caveat: If you're unfamiliar with what "normal fresh" is for a specific bean of course it's going to be hard to tell at which stage it is but it doesn't mean that you wouldn't be able to state a clear preference if presented with the same bean before, during, and after its ideal degassing window.

And double caveat: A bean is not a bean is not a bean. Dark roasts degas much faster than light roasts and there's some wild variation out there in what's grown.

You probably don't want to test 1 day vs 2 weeks. At day 1 the beans have not degassed enough to release all their flavor unless you take special care during the brewing process. Around 1 week after roast is optimal for a regular v60 brew. 2 weeks isn't long enough for the beans to have gone (very) stale. After 3 weeks is when the taste really drops off.

What brewing method did you use, regular cupping procedure?

It was done in one of the Google coffee bars. I don't remember exactly how that works, but you can be sure it was done with professionalism

So you’re saying there should be a difference between 1 day and 2 weeks, but the google story said otherwise, basically no one could tell.

More accurately, not enough people could tell to be statistically significant. This is all explained on the video.

People who say "use 4 weeks" are right. It's just hard to organize a whole lot of these things. We're lucky we could do it once.

Most definitely, but it depends on a lot of factors, like how and when the beans and coffee were prepared. Overly fine ground (maybe with a blade?) dark roast in a filter pot? It's going to be terrible coffee regardless.

A high quality bean lightly roasted and ground perfectly just now in a pour over? Two days ago versus two weeks will be noticeably different, three to four weeks after it'll be obvious.

Edit: I'd like to know more of the variables that went into this. "Most people" I know don't drink black coffee, if they drink coffee regularly, or don't drink coffee at all. If you're used to drinking store bought grinds and using a filter pot (or some kind of pod system) then you're probably already a lost cause here.

You're right about black coffee (I use a teensy bit of milk & sugar myself, way less than a tsp), but for a test you want consistency.

Actually I think the last few days recommendation is off by quite a bit. Most boutique roasters I know about typically recommend to use the beans within 2 month after roasting and some even recommend to not use the before 1 or two weeks after roasting .

A different test would be the grinding one. I am very sure I can taste the difference between fresh ground and ground a day or two ago coffee (for espresso however). I would be interested what you get for that experiment.

Spitballing from the basic chemistry, freshness is mostly about the time before the beans are rancid, the packaging used will hold in volatiles but oxygen + heat will make beans unpleasant. I wince a bit when I see coffee in the coop-style dispensers, that's a recipe for unsavory flavors.

So date-since-roast is also a proxy for likelihood of rough treatment, and it's lore from a world which includes roasted beans which aren't stored sealed in any way. I have had coffee taste fine a month after roast if stored carefully, and in the tropics, fresh roasted beans can go off on you in a few days, if they live in a kraft paper bag at outdoor temperatures and humidity.

The reason I recommended buying coffee within days of its roast is that you'll probably drink that same batch over the next week or more. Things start going downhill after around a couple of weeks off roast. So, if your coffee is 1+ week old when you buy it, it's probably going to be missing something for at least some of the days you drink it.

I drink mostly decaf these days, and it stales even faster than regular. The difference is so stark, that to get a consistent espresso extraction I have to adjust the grind setting finer as the coffee ages. If a 10 on the Niche Zero is where I dial in coffee 4 days off roast, I'll typically need to dial down to an 8 by the end of two weeks.

Still, I don't have any trouble believing the results of your experiment, or the YT video's experiment. Two weeks is still pretty fresh. But if you repeat your experiment with 4-day coffee vs. 4-week coffee, maybe your tasters will be able to detect a difference. (Also, depending on how you prepare it, 1-day coffee might be "too fresh"; it's still outgassing a lot. I'd suggest you try 4-day coffee as your control.) If you try decaf, I'd expect the difference to be more detectable.

Anyway, thanks for the empirical evidence.

Any experiment is going to leave questions, but unfortunately, not many people or places have the luxury of getting 17 people together many, many times.

That said:

> Things start going downhill after around a couple of weeks off roast

"a couple of weeks off roast" is exactly the test we did. It's reasonable to propose other ages and you could well be right that results would be different.

You should try fresh, 30 days, and 60 days. The cafe I worked only adjusted grinds for coffee which was 30 days after the roast date. Allegedly this was decided through many many taste tests.

I wrote this quick guide two decades ago, so imagine my surprise when I stumbled upon it today while browsing Hacker News!

Anyway, a lot has changed since then, so I'll give a quick update.

First, the coffee situation in the United States is much improved. In most towns, you have multiple great coffee shops to choose from. Many fast food chains and even gas stations (!) have pretty good coffee. Nothing like the sour institutional coffee you'd find cooking away in massive vat-like dispensers back in the day.

These days I mostly drink decaf espresso. My grinder is a Niche Zero. My brewing apparatus is a Cafelat Robot, an ingenious lever machine for making espresso (and, I recently discovered by happy accident, 'spro-overs). I also continue to enjoy pour-over coffee, but now I lean toward the Clever Dripper system for convenience.

If I were writing the Guide again today, I'd add the Aeropress and Clever Dripper as great options. I'd still say that drinking fresh coffee and grinding on the spot is the way to go. And, of course, I'd multiply all of the equipment prices by a factor 3.

Anyway, thanks for the trip down memory lane. And do enjoy your next cup!

Blade grinder? Please, do yourself a favour and don't use a blade grinder as they produce a big variation in particle sizes - you need to get a burr grinder (there are cheap ones available) and it should be the most expensive part of your coffee equipment. (Large particle sizes will lead to under-extracted coffee and small particles will lead to over-extracted coffee so you end up getting the worst of all worlds).

Also, get an Aeropress instead of using a filter machine as they tend to over-extract the middle of the filter and under-extract the outsides. Pour-over filters can work-around those problems, but takes a bit of skill. Aeropress uses full immersion so it's much easier to get consistently great coffee out of it without too much skill involved. (I prefer cooler temperatures with the Aeropress - I usually aim for about 80°C)

I used to use a popcorn machine to roast beans and it's great fun though I've moved onto using a Behmor roaster now. If you get a popcorn maker, it has to be one with hot air vents at the bottom rather than a wire grill to avoid the fire risk from the chaff that comes off the beans. It's easy to drill a hole into the top and put some kind of digital thermometer in there to get a good feel for what's happening to the beans.

Or do whatever you enjoy! I've done the whole list (including roasting beans in a popcorn popper! when living in an area where good beans weren't available), and what I've settled on for myself is a hand burr grinder and a small french press. I have an aeropress (with a separate hand grinder set finer), but I don't like the idea of brewing in plastic. I have a pourover, but I don't enjoy the flavour as much. I have a large french press, but I find it gets a thinner filter bed and ends up grittier (plus I'd rather just make two small press pots and have them fresh). I've tried espresso, but I always end up making an americano anyway so why bother? I've used cotton filtered pourover, but the filter kinda grossed me out. I've used automatic drip pot and they aren't bad sometimes (but most people who use them buy cheap pre-ground, which sets you up for failure). I've used vacuum pot (they're a neat gimmick but not an everyday thing in my opinion). I've tried making turkish coffee, cowboy coffee, electric percolator, manual percolator... always wind up back with the small press pot.

I enjoy the process of using a vacuum pot, but I also found the cloth filter was hard to keep clean and non-mouldy.

Hand-burr grinders are great - I can highly recommend the Knock grinders and the Aergrind is my favourite for travelling as it's sized to fit partially inside an Aeropress. I usually aim for somewhere closer to french-press grinds and use the inverted method to give total control over the brewing time.

Edit: A small press pot is going to work in a similar fashion to an Aeropress, though the Aeropress has the advantage in making just a single cup of coffee and completely separating the grounds from the water so that the coffee doesn't keep brewing after being made. I'd love to see a glass version of an Aeropress made.

My small press pot actually makes around 12 us fluid ounces of coffee at the strength I like, with a fairly thick filter bed. Almost identical shape and dimensions as an aeropress, so it works interchangeably in that regard.

I agree, would be great to get a glass aeropress cylinder - though what makes me most hesitant to use one is actually the plunger/seal. I had one that I bought about 10 years back that sat for a couple months without use and it got very tacky and sticky, and it was very difficult to clean off. I'm not sure what that material was, but the fact that it isn't there when I used it regularly told me that whatever it was, it was going into my cup. Now when I use (my new aeropress), I wash the plunger first and I don't brew inverted - ensuring that my beverage doesn't come in direct contact with the rubber part.

I've had the sticky plunger happen to me when my work aeropress was sat unused for a few months. I thought it was the sunshine/UV degrading the rubber and didn't really think about whether it puts contaminants into the coffee - I just bought a replacement rubber bung for it (they do wear out over a few years usage as well).

Edit: Just looked it up and the plunger is made out of thermoplastic elastomer (food grade)

Edit2: Found a discussion about a glass aeropress and there would be a couple of drawbacks. Firstly, the glass would likely need to be pre-warmed due to the increased heat capacity. Secondly and more importantly, glass wouldn't be strong enough to survive daily usage and I know I've certainly dropped my aeropress onto the floor enough times to know that indestructible plastic is definitely better for me.

They actually changed the seal material to silicone in 2018[1] - that's why I got a new one to try. So far so good!

[1] see the fourth last answer in their faq https://aeropress.com/pages/faq

If you're inclined to futz more with your gear you might really enjoy a Hario Switch. It's an immersion + percolation brewer that takes paper filters and is made of glass.

I have almost your exact preferences and settled on this as a great middle-ground between futsiness and taste. I do a sort of vietnamese coffee that's clean, strong, forgiving to brew time and grind, well-extracted and easy to clean up. Can't recommend it enough!

Sounds like a good candidate for next time I want to try something new, thanks!

My pleasure! I guess I wrote all that without really explaining what the difference would be: a much cleaner cup from the paper filter vs the french press mesh.

If I use my large french press (which tends to have a thinner filter bed), I sometimes will pour it through a paper filter set in my ceramic pourover to accomplish the same thing.

Wow, you've tried 'em all!

This is awesome. Instead of listening to some "expert" tell you what to do, just try it yourself. Like I said: I know I can taste bamboo vs. paper filters, so I don't need to care if other people can.

I endorse Sweet Maria's! I've been ordering from them every few months for many years, and I think they're great. Aside from good raw coffee, they usually add a little postcard or other nice touch inside the package as well. Last time I got a whole (empty) burlap coffee sack that must have come from the grower. Neat!

I also use the popcorn-popper roasting method and with just a little practice turns out excellent results. I've been doing it this way for 10 years. While I could upgrade to a fancier roasting method, I've never found the need. If this seems like too much time/work considering it's 15min of constant attention over the stove, consider whether it's any faster to go out and buy pre-roasted coffee.

One word of caution on the espresso section of the article: I think his price-point thresholds are too low. I don't think you will have acceptable results less than double those numbers. You might get away with a $300 grinder, but even $500 is at the very lowest end of an acceptable espresso machine. You're better off with pour-over then.

I found using the popcorn machine for roasting took too much attention, but here in the UK I had to adjust for external temperatures and resorted to putting the machine in a large cardboard box during winter to get the temperature high enough (re-cycling the hot air) which of course is a bit of a fire risk. Also, you can only roast quite small amounts at a time (e.g. 100g) whereas my Behmor can happily handle 150g, but doesn't need constant watching.

Edit: Just realised you're likely using a stove-top popcorn maker which I've never tried. I used an electric hot-air popcorn maker which has the advantage of blowing the beans around so they roast evenly and also blowing the chaff out of the top/side chute (outdoor usage recommended).

Yes - for clarification I'm talking about using a stove-top whirly-pop style pop-corn-popper. I can do about 250g at a time.

I'm someone who doesn't drink a lot of coffee. I've noticed co-workers, often, who will be cranky and apologize in the morning hours because they are dependent on caffeine to function.

This seems like a bad state of affairs when what 90%? of developers are dependent on caffeine to function.

A good excuse to be cranky in the morning is worth the price of addiction.

Michael Pollan has an interesting take on being addicted to Coffee. He suspects most of the modern world is thanks to caffeine and coffee breaks. His conclusion is: although there are some 'negative' side effects, those effects are minimal and the positive effects outweighs them considerably.

Not denying that caffeine addiction is real, but I also think "lack of coffee" has become a sort of blanket excuse for just being sleepy or not fully energized, regardless of the actual coffee intake. It's a common thing to just say, sometimes as a joke and other times as a convenient lighthearted excuse when someone misses a social cue or does something silly: "Sorry, haven't had my coffee yet!"

And most people who hear it kind of get it as well. They don't _actually_ think this person is physically addicted to caffeine. They hear it with the understanding that this person is just a bit tired, distracted, or out of it that morning/day/whatever.

Assigning some reason to anything someone wants to say is the most common conversation pattern I consistently see. It's not specific to coffee. People may be cranky, but the excuse that it's because they haven't had their coffee yet is an ad-hoc justification. If you handed them a coffee to drink in that moment, they would just have another excuse.

It's the same conversation pattern that people follow when they say: "I think X, because Y". You then go and show they that Y isn't true. They come back with "Ok, but I still don't like X". Y was never relevant.

I am so glad that availability of good coffee has improved since 2002.

I will admit though, sometimes nothing hits the spot like some cheap instant and non dairy creamer though.

>I will admit though, sometimes nothing hits the spot like some cheap instant and non dairy creamer though.

Depends on where you are I guess. If you're in a big city with tons of options for gourmet coffee then cheap instant is an awful proposition.

However, if you're on a multi day hiking trip through the mountains with your tent and sleeping bag, then a hot cup of instant in the morning will taste like angel juice in your mouth.

I'm in a small city, but it has a bunch of extremely good local roasters and cafes (along with a thriving food scene).

I can go get gourmet coffee easily (walking distance), or buy extremely good beans, but heck - sometimes I want absolute shit tier coffee. Its what I grew up on!

Yeah I saw the date before I read the article, and the thing that struck me is that specialty coffee wasn't very good. I grind at home and have a midtier home espresso machine, but I still treat myself to a local cafe espresso drink from time to time. I just can't compete with a commercial espresso machine, or experienced barista for that matter.

I also think you'd be hard-pressed to find robusta served outside of a diner these days

Yeah, even Walmart-brand instant coffee is Arabica.

A Coder’s Guide to Coffee (2002) - https://news.ycombinator.com/item?id=22026141 - Jan 2020 (4 comments)

A Coder's Guide to Coffee - https://news.ycombinator.com/item?id=620157 - May 2009 (55 comments)

A coder's guide to coffee (cheap, easy, and delicious) - https://news.ycombinator.com/item?id=88228 - Dec 2007 (16 comments)

I do not feel it’s right to “Buy only whole-bean coffee roasted within the last few days.” - what should we do with coffee that was roasted weeks or even month ago? Throw it away? My mantra is to never throw away food - I will keep on drinking my coffee until I’m done, then I’ll move on to the next pack. Difference is so small that it’s not worth it.

I don't think anyone is telling you to throw away old beans - the author is just providing accurate information that beans go stale in a couple of weeks and that you should try to plan accordingly if you care about good coffee. Avoid buying old beans. And don't overbuy fresh ones thinking you're going to keep a 2 month supply around.

Just buy what you think is a 2 week supply, and when that's gone go buy another 2 week supply.

And if you don't care about optimizing your coffee experience - that's cool tool. Most of us have better things to worry about.

The assumption here is that you are buying them fresh and then using the entire bag within 1-2 weeks (while they are still fresh). If you don't go through coffee that fast, then that probably doesn't apply.

A lot of instant coffee (3in1 or 2in1) these days are quite good especially from Vietnam. In Asia, these are quite commonly sold in supermarket. In western countries not so much (guess quality of living in the west are lower than Asian sides these days). Seriously speaking, non of the coffee either self-roasted or instant able to match coffee luwak. If you are coffee afficianado, luwak is a must.

>coffee luwak. If you are coffee afficianado, luwak is a must.

Do you mean Kopi Luwak, the coffee from Indonesian civet poop?

According to James Hoffmann[1], people should stop consuming that as the industry is based on animal abuse and it's nearly impossible to verify your Kopi Luwak has been gained through fair practices that haven't harmed the animals.

If you are coffee aficionado then better stick to Fairtrade coffee that doesn't involve any animals.

[1] https://www.youtube.com/watch?v=pkbuFwHnJQY

I think most "kopi luwak" nowadays is produced chemically, rather that using a weasel's digestive system (OK, that's "chemically" too, but you know what I mean :)

A while back I visited a kopi luwak farm in Vietnam, Hue I think it was. The animals were treated really well, but I'm sure that's not going to be the case for all these places.

Anyway, kopi luwak really is amazing stuff - but at the farm I tried "weasel coffee" and "chemical coffee" side by side (the same beans, with the same grind and roast), and I couldn't tell the difference.

> non of the coffee either self-roasted or instant able to match coffee luwak. If you are coffee afficianado, luwak is a must.

If you're a coffee afficianado, watch this video [0] and don't try it.

[0] https://youtube.com/watch?v=pkbuFwHnJQY

> If you are coffee afficianado, luwak is a must.

No, it is not. If we disregard the ethical issues surrounding the coffee, this is what a renowned roaster has to say about the coffee

""" Kopi Luwak. Made from poop, smells like poop and tastes like poop. A complete ripoff to buy in to… """

Totally agree. Also, Kopi Luwak will likely by very stale indeed unless you buy it from a specialist.

A much better version of poop coffee is Jacu Bird coffee. They tend to live around good quality coffee plantations and they have a discerning eye for the coffee cherries. Still more of a novelty thing though as it's so expensive. AFAIK Jacu birds aren't force-fed in captivity, so that's much better.

Personally, I can't stand instant coffee and treat it as some kind of insult to decent coffee (I always choose tea in preference to instant coffee). As others have said, Kopi Luwak should be shunned for the animal cruelty involved as well as for the the excessive hype about it.

I am a fan of quite a few Asian coffee beans, however. Monsooned Malabar is one of my faves as well as some strong flavoured Indonesian beans. I really enjoyed some Thai beans that I bought in a small batch although the flavour was definitely funky and not to all tastes.

The best is any pour over or drip with paper filters.

Methods that don't use filter cause a rise in bad cholesterol[0] if you drink a lot of coffee.

[0] https://academic.oup.com/aje/article/153/4/353/129046

The cholesterol issue was part of the reason that the Aeropress ships with paper micro-filters, but they also filter some of the tasty oils out too. I prefer using a permanent metal filter with mine as I prefer the taste.

Drip filter machines are ghastly - over-extracted through the middle and under-extracted at the edges. Also, people always seem to skimp on the amount of grinds they use (or maybe I'm habituated to super strong coffee).

I tried a metal filter in my aeropress for some time, and the coffee was noticably worse. Much more acidic than high-quality paper filters (the aeropress brand paper filters are merely okay). A good paper filter can make good coffee great.

> Also, people always seem to skimp on the amount of grinds they use (or maybe I'm habituated to super strong coffee).

Couldn't agree more. Especially since the extraction is so uneven, you need a ton of grinds to make good coffee. Some of the better machines distribute water more evenly. There was a stretch when I used a drip filter daily and I disturbed the grounds half way through. Regardless, I find myself absolutely packing in the grinds to make a decent pot, whereas my beans go much further in a pour over or aeropress.

I'm very lazy so although I've several machines (drip coffee, french/moka press, nespresso) the one I use all the time is my full auto.

Input: grains, water Output: coffee

Buy a JURA coffee machine (pricey but worth it) and call it a day.

I got an expensive JURA for a wedding gift couple of years ago and it's awesome. Can someone please tell me if there's something I'm missing by not geeking out about coffee? I mean the coffee that thing makes tastes great, but if I haven't tasted really good coffee I wouldn't know I'm missing out ;)

If it's grinding beans to order then as long as you're not buying stale beans, you should be fine as you are. As I see it, the most crucial factor is water temperature (it bugs me to see boiling water used for coffee) and the freshness of the beans is the next important factor (somewhere from 3 days after grinding to two weeks is best).

Thanks! As far as temperature goes I do recall a setting somewhere, I'll check it out. As for the beans, I buy them from a good retailer and I buy more or less 3 months supply at a time.

Moka Pot is the way imo - thick, rich tasting coffee that can be used like espresso (in a latte or Americano, etc...) made by a simple and easy to clean device.

Four Sigmatic with Lion’s Mane has enabled me to get down from 10+ cups daily to one cup daily. I prepare it with an aeropress.

Lavazza made in a Bialetti Brikka. Done!

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