coffee math

We all love that cuppa joe first thing in the morning, or several, and maybe throughout the day.  That was me when I was working.  But for the past 3 and a half years caffeine has been just a pleasant occasional distraction.  Maybe that job wasn’t so stimulating after all.

But nowadays a simple cuppa just isn’t enough.  Ever since Howard Schultz started rolling Starbucks over us in ’87 (1), that brew’s gotta swim with some fuzzy milk.  Never mind his coffee is swill, overpriced and overroasted – burn, baby,  burn! – with way too many preciously named varieties to choose from.  The die is cast: latté or cappuccino, please!  And if you’re tried to order one of the latter in a proper coffee shop, you’ll realize ol’ Howard has supersized that drink from the dainty cup of dessert beverage those monks intended.  You can’t get a cup of coffee for a dime anymore, maybe a buck.  But count on wasting the better part of a 5-spot for one of those milky numbers.  It can add up.  Every list I’ve seen from a financial counselor advising ways to save money lists cutting out, or cutting back on, Starbucks.

But I love my lattés, a lot!  Well, it’s just coffee – anyone can make that – and milk – easily foamed with some simple equipment.   In my house, we’re on our second espresso maker/frother.  The first, a Krups, set us back ~$200 and served us well for many years.  For Valentine’s Day 2008, I was looking for something special for my cappuccino loving sweetheart.  I splurged and bought a Rancilio Silvia M.  You can get one on Whole Latte Love (WLL) for less than 900 bucks (2).  It’s been well worth it.  It’s still going strong, needing only a little tinkering now and then.  I get my sweetie out of bed every morning by carrying to her the nice big triple cappuccino I’ve just made. 

She loves it and I swear the practice lets me get away with all sorts of other stuff.    I like ‘em too, making myself one maybe once a week.  If that model’s not to your liking, Whole Latte Love has 371 others from 21 manufacturers ranging from Bezzera to Rocket Espresso.  Prices run from $49 to $9400, with many on sale (3)!  If you want to take a flyer on slightly used, there’s e-Bay, with over 9500 listings (4).

 The other good coffee capital investment is a proper grinder.  We’re on our 4th or 5th, finally graduating from Krups when we got one when we bought our Rancilio.  I know you can buy coffee already ground, or ground at the store, but you can’t beat the freshly ground bean, its many freshly jagged edges having minimal time to hydrate.  We love our Baraza Virtuoso.  If you’re noticing something about the names so far, you’ll know which country takes their coffee molto seriamente.  .  The machine is very simple, just a hopper, adjustable burr grinder, and the spilt ground tray.  

The burr has needed attention a time or two, but WLL has helped Kathy diagnose the problem, sent her the necessary part, and talked her through the repair process.  Today’s Virtuoso has added a timer and will run you 250 bucks (5).   As with espresso machines, WLL offers variety, with 193 models from 20 different manufacturers, ranging from Baratza to Yama, costing from 170 to 900 bucks (6).  Of course, once you’ve set up your fancy expensive home coffee shop operation, you’ll not want just any beans.  Best to identify a local roaster and get those beans as fresh as possible.  We’re fortunate to have two of those in Tree Town, and we are friends with the owners of both.  Dave and wife Nic’s Mighty Good Coffee has been at it since 2006 (7).  Nic was an AA in my Division for a while as Dave was getting things off the ground.  Tall, pretty, and funny, I was sad when she left.  John started RoosRoast a year before Dave (8).  Both also run coffee shops in town.  We prefer Dave’s Espresso 46 and David’s Dark Decaf for espresso drinks and John’s rotating Small Batch single origin varieties for regular coffee.

The stuff is not cheap, with Dave’s 12 oz bags running $14.69 and 12 ounces of John’s running $14-$17 depending on variety.  But well worth it.  Neither Kathy nor I are the coffee hounds we were when we were working.   One maybe two preparations a day, tops, but always pure pleasure from first smell to last sip. 

We decided to run the numbers recently.  Figuring five bucks a pop on the capp, conservatively estimating 6/week, 50 weeks a year (we don’t take our machine on the road), we’d be spending $1500/year for an equivalent amount of cappuccino from a coffee shop.   By this past Valentine’s day, we’d been doing this 15 years. That’s $22,500, excluding interest.  With the Rancilio and grinder costing a little over a grand total, how’s that for ROI?  Of course, there are materials costs for each preparation.   I use 23 grams of beans to make 3 shots (all at once) for Kathy’s triple capp.  With 28.349521 grams/ounce, that’s 0.81 oz per preparation.   With Dave’s beans costing $14.69/12 oz, that’s $1.22/oz, or 99¢/capp.  Call it a buck to make it easier.  Then there’s the milk, of course.  At my last trip to Busch’s, a gallon of skim cost $4.49.  I half-fill the frother pitcher, strictly by eyeball.  I measured it today for the first time, just for this piece.  Comes to a full cup, almost exactly.  With 16 cups to a gallon, I’m spending 28¢ for the frothy component of Kathy’s capp.  So the materials cost of a triple capp is $1.28.  How much did you pay for that last Starbuck’s again?   Taking it back to that ROI calculation, the 4500 triple caps brewed from Valentine’s Day 2008 to Valentine’s Day this year, if we’d paid Biden ’23 era prices, cost $5700, or $16,800 less than store bought.  That Rancilio and Virtuoso are still looking like a pretty good investment.

There are 2 other – much less expensive – pieces of equipment that I find essential to the way I brew coffee.  Actually, now 3.  The first is a digital scale.  Now, I’ve been accused of being an anal retentive chef (9).  But I took to measuring beans as I was getting tired of struggling with the portafilter.  That’s the device that holds the basket that holds the grounds that you screw onto the espresso machine for it to pump steam and water through to make that shot.  Somehow, the scoop would often give me just a little too much, begetting the portafilter struggle dance, cursing the machine , scraping off some grounds, trying again, repeating until I finally got the damned thing on.  I found that scoop and beans weighing 32 grams gave me a perfect fit.  The scoop weighs 9 grams, but I don’t go through the tare process.  You can get a decent scale for less than 12 bucks on Amazon (10).  With many other kitchen and postal applications, you’ll be glad you bought one.   Then there’s the water kettle.  C’mon, you say, how hard can it be to boil water?  But if you’re pouring boiling water over grounds, you’re burning them a bit.  Do you want your coffee to taste like Starbucks?  I know, we’ve been talking about espresso machines, which handle all that heating automatically, but if you’re doing regular old drip coffee, or using the neat little apparatus I’ll be telling you about shortly, you’re in charge of the water going over the grounds.  The Coffee Brewing Handbook published by the Specialty Coffee Association states that a water extraction temperature of 92–96 °C (1980F-2050F) is optimal for drip coffee (11).  However, scientists in the department of Food Science at UC Davis assessed coffee qualities drip brewed with water at 870C (1890F), 900C(1940F), and 930C(1990F) and found that coffee brewed at 870C retained all the qualities of coffee brewed at higher temperatures, recommending using the coolest temperature as the resultant cuppa is less likely to scald (12).  I actually heat the water only to 1750F.  Tea should be brewed at even lower temperatures, varying according to type of tea (13).  So having an apparatus to heat water to a selected temperature, rather than just boiling is, is advantageous to the meticulous brewer.  Amazon  has 6 pages at 48/page and 22 on the last page (there were some dupes, you do the math) ranging from a little more than 20 bucks to some high end numbers well into 4 figures (14).  I like my minimalist Consori just fine, which set me back a little over 50 bucks (15).   

A late addition to my coffee side gadgets is my hand tamper.  I made plenty of espresso without one, but what I make now using my tamper is better and much more consistent batch-to-batch.  There are many forms of hand tampers – WLL has 136 tamping tools from 21 different manufactures arranging from Asso Coffee to WLL itself, priced 224 to 190 bucks (16).  My little Espro cost me 90 bucks, perfectly fits my 58 mm basket, has some nice heft, and clicks once pressure applied to the grounds reaches 30#/PSI.  Not all tamping tools have this feature.  Why do this?  Tamping removes gaps and air pockets between the coffee grinds, creates a tight seal around the edges of the portafilter and when done correctly, creates a flat and even bed of coffee for the water to through, promoting an even extraction of flavor (17).  With the pressure feedback, you do it the same every time.  Whether you. uy a tamper with or without the pressure option, be sure it will fit sungly in the diameter of the basket in your portfilter.  A single press on the grinds is what you want, not multiple daubs.  Espresso makers often come with cheap simple tampers, but they tend to fit.

If you want to get real cheap, here’s what you do.  Buy yourself an AeroPress, a simple apparatus that makes a shot of coffee by having you pour the ground coffee in a cylinder, followed by hot water, stirring, then pushing a plunger down that forces that mix through a paper filter (18).  Not exactly a shot of espresso, but pretty darn close.  I’ve been making triple capps for my sweetie by grinding those 23 grams of beans that would have one into the

portafilter basket and dumping them into the AeroPress cylinder.   Then you get yourself a frother, whose spinning blades whip up some foamy milk.  Combine the two and there’s your latte, or cappuccino if you really whip up the milk.  An AeroPress costs about 35 bucks, and frothers can be had for less than that (19).  Take care shopping for milk frothers, as there are hand-held stirrers that also list in that category, but really don’t do the trick and are messy.

One beauty of this system is you can take it into the office, where if you’ve got a way to boil water and keep milk cool, you’ve got all your ingredients.   It’s what my sweetie did for years, although in place of the AeroPress she had a Keurig.

As Thomas Jefferson said “Coffee is the favorite drink of the civilized world” (20).  I hope my calculations and demonstrations have shown you a way to stay civilized without going broke.


1. About Us.

2. Rancilio Silvia M Espresso Machine.  Whole Latte Love.

3. Espresso machines.  Whole Latte Love.

4. ebay.  Espresso machine.

5. Baratza Virtuoso + Coffee Grinder.  Whole Latte Love.

6. Whole Latte Love.  Coffee and espresso grinders.



9. Anal Retentive Chef -Saturday Night Live. YouTube.

10. Etekcity Food Kitchen Scale, Digital Grams and Ounces for Weight Loss, Baking, Cooking, Keto and Meal Prep, LCD Display, Medium, 304 Stainless Steel.

11. Lingle TR. The Coffee Brewing Handbook: A Systematic Guide to Coffee Preparation.  Santa Ana: Specialty Coffee Association of America, 2011.

12. Batali ME, Ristenpart WD, & Guinard JX. Brew temperature, at fixed brew strength and extraction, has little impact on the sensory profile of drip brew coffee. Sci Rep 10, 16450 (2020).

13. Why Water Temperature is Important When Brewing Tea.  RISHI TEA AND BOTANICALS.

14. water kettle temperature control.

15. COSORI Electric Kettle Temperature Control with 6 Presets, 60min Keep Warm 1.7L Electric Tea Kettle & Hot Water Boiler, 304 Stainless Steel Filter, Auto-Off & Boil-Dry Protection, BPA Free, Black.

16. Espresso Tampers.  Whole Latte Love.

17. Tamping Coffee. Zando.,an%20even%20extraction%20of%20flavour.

18. AeroPress Original Coffee Maker.

19. Bodum 11870-01US Bistro Electric Milk Frother, 10 Ounce, Black.

20. Carter M.  How the Boston Tea Party Turned Americans into Coffee Drinkers.  Behind the Cup 7/7/22.,party%20did%20not%20go%20unanswered.

    Published by rike52

    I retired from the Rheumatology division of Michigan Medicine end of June '19 after 36 years there. Upon hitting Ann Arbor for the second time (I went to school here) it took me almost 8 months to meet Kathy, 17 months to buy her a house (on Harbal, where we still live), and 37 months to marry her. Kids never came, but we've been blessed with a crowd of colleagues, friends, neighbors and family that continues to grow. Lots of them are going to show up in this log eventually. Stay tuned.

    2 thoughts on “coffee math

    1. That’s a lot about coffee! I Like a espresso once in a while. I started driving truck in 72 back then there were no fancy coffee shops just truck shops with diners in them they only had one coffee it was called 500 hundred mile coffee that was it sill drink it today If you want to have some fun go into a fancy coffee shop and ask for a large coffee don’t say anything more, the server face will go blank and they will stutter and what do you want in it and you respond coffee they will have a meltdown


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