Here is the result of my first experiment in cold brewing coffee. The picture attached is my actual setup from my actual kitchen.
I used 2 cups of beans with 8 cups of filtered water out of our faucet Pur system. I’d never ground that much bean at one time, and realized that it just barely fits in the receptacle. I might well do it in halves next times. I reused the plastic container from a 2.5 pound mixed nuts tub from Costco and the water and grounds just barely fit in this. I chose to put in half the water first, spoon the ground coffee in, and then fill it back up. I didn’t want to have clumps of coffee stuck to the bottom of the container, and I didn’t want to just dump it all in, also to avoid clumping. After putting in the coffee, I filled it up with the rest of the water and very gingerly stirred it up to avoid splashing it out. When that was done, I screwed on the lid tight and let it sit overnight for about 14 hours.
The worst part of the whole process of the full-sized batch was the logistics of filtering the coffee. I put in a basket coffee filter from an old coffee pot, which didn’t quite fill up the strainer and set the strainer on this big glass bowl. On first pour, a giant lump of grounds fell into the strainer, overflowed the filter paper and went everywhere. Three seconds into filtering, I had an unacceptable level of grounds in the liquid. I dumped the filter paper, rinsed out the strainer, dumped the contents of the bowl back into the tub and washed out the bowl. Having returned the liquid back into the tub, I tried filtering agin more carefully this time. It worked fine but I had to go very slowly to avoid overflowing the coffee filter inside the strainer. There were enough grounds that I had to empty the filter one more time in the middle and put in a third and final coffee filter. When it was finally in, I tamped the grounds down a little with the spatula, dumped the grounds and transferred the contents of the bowl into the pitcher. As I poured it in, the liquid in the pitcher bubbled in an interesting way. I have no idea what was happening chemically but it looked really cool. Before I put it in the refrigerator, I poured myself the first cup, added water and heated it. It tasted great.
I bought the strainer and the pitcher from Dollar General to avoid putting coffee funk in any of our existing pitchers. I’m hoping the pitcher seals relatively well. It remains to be seen how well this will keep over time but I am being optimistic until it is proved otherwise to me. The total outlow in materials was under $7 and if the experiment ever stops, all of the stuff I bought can be used generally in the kitchen. I had looked at things like the Toddy T2N Cold Brew System but didn’t want to either spend that money or put more kitchen gadget crap in our house. Assuming that the concentrated coffee tastes as good at the end of the pitcher as it did at the beginning, I’ll call this a big success. I’m worried about oxidation and/or reaction with the plastic of the pitcher, but will assume it is good until it stops tasting good.
The only part of the process I don’t like is the filtering. I think the first adjustment I’ll make is to ditch the coffee filter. I will either get a pack of the huge filters they use in restaurant coffee makers or just line the strainer with paper towels and call it good. Longer term what I’d like to do is somehow rig together some way of taking two of those lids from the nut tubs, cutting out the middles and putting a filter between them and then affixing them together securely. If I had that, what I would do is to steep with a solid lid, then screw on the filtering lid and a second empty tub on the other top of it. Then I’d just turn the whole thing over like an hourglass and let it drip until it stops. That would be way less trouble than what I went through, would eliminate dirtying up the glass bowl and would keep the whole “dirty” part of the process in disposable bits that can be thrown away at will. We buy those tubs of mixed nuts periodically anyway, so we have a steady supply of them.
All in all, this has been fun. I’ve enjoyed playing with the process and tasting the results. I’m calling this a provisional success. If the concentrate fails to hold up, I’ll get a better storage mechanism. Other than that and the possible filter improvements, I’m good with what I have. Onward to a coffee full future!