How to make consistent cold coffees?
I make 1-2 cups of cold coffee daily and sometimes for my SO and small inconsistencies have started driving us crazy. Some days it would be perfectly cold and creamy and other days a watery sludge. After months of trying various things and drinking a lot of coffee, I’ve discovered that making consistently great cold coffee comes down to understanding a few key things.
Success criteria for my coffee:
- Must stay icecold for around 15min. I usually finish it by then
- Thick, creamy texture throughout and shouldn’t turn watery like cold brew after sitting on my table for 10min
- Should take less than 1 min to make
Here is what I’ve learnt from my super scientific and rigorous experimentation:
- Shake it, don’t stir it
- Stirring is useless. What takes 15 seconds of shaking needs like 2 minutes of violent stirring to achieve the same results
- Shaking also mixes the drink more uniformly. Stirring always leaves some coffee/sugar at the bottom of the cup
- Shaking also aerates the coffee with micro bubbles giving it a foamy texture (which stirring doesn’t)
- I don’t seem to observe any benefit in over shaking(things seem to plateau after like 20sec of shaking) or how intensive/vigorous I do it (thankfully so)
- You need lots of ice
- There is no problem with using too much ice as they stop affecting temperature or dilution beyond the equilibrium point. So, always ensure to have more ice than needed when you start. I use roughly 200g of ice for 100ml of coffee. It seems excessive but actually achieves ideal temp and dilution
- If you have very little ice, it will result in poor chilling and will end up over diluting your coffee. This is sometimes counter intuitive. You actually want to use more ice, not less, to prevent over-dilution. More ice equals faster chilling because you have more thermal mass to absorb heat quickly, reaching the target temp before too much of it melts.
- There is no problem with using too much ice as they stop affecting temperature or dilution beyond the equilibrium point. So, always ensure to have more ice than needed when you start. I use roughly 200g of ice for 100ml of coffee. It seems excessive but actually achieves ideal temp and dilution
- Size of the ice cube matters (sometimes)
- Ice cube size does matter if you are planning to let your coffee sit on your table for more than 20min. Bigger ice cubes are better because they have smaller surface area per gram and thereby melt slower which has an added benefit of diluting your coffee slower over time
- The size of the ice cubes doesn’t seem to matter for shaking (you end up with similar temp and dilution after 20sec) although theoretically smaller ice cubes chills marginally faster due to more surface area but I haven’t noticed this
All in all, it personally takes me less than a min to assemble all this and the results are fairly consistent