I suppose I can believe people will do anything-- and even a tablespoon of pure caffeine can mess you up, in case you mistake it for sugar- but 50g? That’s insane, and so would be the intended 1/2 bottle of No-Doz. Kids know basic facts like that even a gram of let’s say Cocaine HCl is “a lot”, right?
Way back when (1930s-40s??), we are told people in Soviet prisons would prepare tea using something like 5-8 tablespoons per person. I’ve done that myself, but then they went on to brew it basically overnight…
Also just to add to the discussion, Keurig mentions that each coffee pod can be used for 2 servings but mention that the second cup will be not as flavorful. So there seems to be ‘room’ for a slower brew.
I can fill my 24oz cup with 2 10oz brews from one pod, plus a little whole milk & sugar-free syrup. I set most of them on “strong” for both cup. and pour them in the cup. Usually, it’s plenty strong, with 2 plebtsa. No grounds get in it. It’s good.
Okay, I now realize all my comments concerning my experience with capsule coffee machines (Lavazza, Nespresso, etc) and with regular espresso machines are based on 1 normal shot = less than 1 oz. So no idea what the Keurig machine in question does to make 8 or 10 oz; I use different techniques to make that much coffee but not an espresso machine (that would be a decuple espresso!)
One way to get a large amount of strong coffee is to grind the beans coarse; boil your 10 oz or 24 oz or 30 oz or whatever of water, then turn off the heat (this isn’t black tea), stir in 2-3 tablespoons of coffee per cup, plus sugar if you want, stir slowly for a bit, then let it infuse for 5 minutes and finally pour off or strain the coffee. You can use a French press, of course. The point is, compared to an espresso, you use a coarse grind and steep for much longer. (To be precise, espresso is not steeped or decocted, espresso means hot water is forced through ground coffee.)
I’m not familiar with how the Keurig machine works, but for most coffee, the water is gravity fed. Meaning it just falls through the coffee grounds. There is no way for the machine to “run the water more slowly”. Even in an espresso machine, the pump only has one speed. It’s on, or off. The flow is controlled by the grounds themselves. Finer ground coffee makes the flow slower, coarser coffee makes the water flow faster. So this is the variable people change when they want to “dial in” a brew. They’re looking for 25-30 seconds for espresso, or 3-5 minutes for a pour over. If it’s not right the first time, adjust your grinder and try again. I would be very surprised if a Keurig machine had any kind of flow control. So my guess is that “stronger” just means “less water”.
My understanding (I’m a self educated coffee connoisseur, but not an expert) is that caffeine is one of the very first compounds to be pulled out of the grounds and into the water solution. So basically, all brewing methods or “strengths” have the same caffeine content. If you want more caffeine, you need to use more coffee. Other compounds and flavors come out later, in a certain order. That’s why you want to shoot for a particular brewing time. If you brew for too long, all sorts of nasty, bitter flavors come out of the beans. If you don’t brew long enough, none of the good flavors come out. But the caffeine pretty much always does, right away. So I don’t think you can control the caffeine content through brew method like you can for the other flavors in coffee.
Water doesn’t flow through the Keurig pod by gravity alone; it’s pushed through the pod. Letting it sit in the pod a bit longer before injecting additional water to push out the coffee water is what extracts more flavor from the grounds.
A Keurig has fairly close control over the brewing cycle; it pumps in a volume of water at a set pressure and temperature to ensure water flows over all of the coffee in the pod (as opposed to blasting through a little channel in the middle) and for a specific brewing time. It isn’t just a scaled down drip coffeemaker.
The water reservoir is at the base of a Keurig, and the pod is at the top, so it has some kind of pump. If it has a pump, then the speed of the pump can be controlled. Since the coffee comes out a small hole in the pod, and not the large hole of a drip machine, you really can steep the coffee at different rates, and this must be what they do, as someone else already explained.
(bolding mine) Not trying to be snarky, but this is a pet peeve of mine - why would someone answer a question in the GQ forum about the workings of a specific machine without knowing anything about the specific machine? A quick Google would have straightened you out (or reading previous posts in this thread).