In this video, I show how I prepare my brew water with a 4L of distilled water and the Rao/Perger concentrate detailed in this blog post.

At first, I show you the material I used:

- A 4L of distilled water
- A Hario coffee spoon
- A small glass with the same diameter as the Hario spoon
- A glass pipette
- A bottle of concentrate
- A brew scale

The 4L of water I start with is actually not exactly distilled water, but rather microfiltered ozonated water. This is practically the same thing, as microfiltering leaves water with a very low amount of total dissolved solids (1-2 ppm), and the ozone kills all bacteria (no ozone is left in it).

I like to use the Hario spoons because they have a hydrophobic coating that causes liquid to pearl and makes it easier to transfer all concentrate into the brew water.

The bottle of concentrate that I use is a food grade plastic dressing bottle (I found this one at Stokes, a Canadian cookware shop). I like it because it is not perfectly hermetic (allowing the concentrate to degas), has no metal parts (which would quickly corrode) and it is easier to share. As you can see, the Rao/Perger concentrate precipitates after a while, and thus I need to shake it thoroughly before using it.

The glass pipette is also easier to clean than a plastic pipette, which is important if you don't want to affect the content of your concentrate.

This particular recipe requires 4 grams of concentrate per liter of distilled water, so I used 16 grams of concentrate. I placed the glass on the scale, the Hario spoon in the glass and I tared the scale. I then used the dressing bottle to get slightly more than 16.0 grams of concentrate, and used the glass pipette to correct and get exactly 16.0 grams.

I then carefully poured the concentrate in the bottle. I brought it closer to the camera to show how the last few drops of concentrate are pearling in the Hario spoon. I then poured a bit of brew water back in the spoon to rinse the last few drops of concentrate, and poured that back into the brew water. Finally, I shook the brew water thoroughly and left it rest for about 10 minutes before using. I always keep both my brew water and concentrates in the fridge, to avoid any bacterial build up. If you haven't used your brew water in a while, it's good to smell it and make sure it doesn't smell like an old towel (this is caused by bacteria and may affect the taste of your coffee).

Let me know if you have comments or questions !