A cold brew is quite simple
Which coffee is best for a cold brew? Generally, we can use every coffee for a cold brew. But there are some coffees available which suit a cold brew much better. With lighter and medium roasts for filter coffees, we will have much tastier results due to the quantity of preserved aromas. Dark roasts have less acidity but much more bitter compounds. It just doesn`t work right.
The best grind size is a medium one. If you use a very fine grind size, such as for an Espresso, an over-extraction will occur and we have a considerable bitter coffee.
A cold brew is quite simple, just leave the ground coffee in cold water for some time. I recommend 100g ground coffee per one litre of water. Due to the permanent extraction a lot of bitter compounds will dissolve from the coffee, therefore I endorse a maximum extraction time of 15 hours before straining the coffee through a paper filter or a very fine sieve.
A really nice cold coffee can be done using a Cold Brew Dripper. The advantage is a round coffee without any over-extracted bitter substances, just purely aroma notes. Using a Cold Brew Dripper an evenly extraction takes place. One drop every two seconds will result in approximately 115ml coffee per hour.
If the cold brew or the cold drip coffee is too intense you can add cold water when serving.
You can also try using Tonic Water instead of water for a Coffee Tonic, the bitterness of the Tonics fits perfectly with the aromas of the coffee!