Last week I posted about a new brewing method I was experimenting with, aimed at keeping the water temperature of the brew in the optimum extraction range (i.e. 90-95°C) for longer.
What’s wrong with the standard method?
In the standard method, you allow the water in your kettle to cool after boiling to around 95°C before adding to your cafetiere. The problem is that once the water is poured into the cafetiere, the cafetiere sucks heat out of the water until the cafetiere and water are at the same temperature. Even with pre-heating the cafetiere, inside a few seconds of adding the water, the temperature has already dropped by 4-5°C. As the temperature will continue to drop by 2-3°C every minute during the brew, the time spent in the optimum extraction range could be less than 1 minute.
The Reverse Brewing Method
In the reverse brewing method, water is added to the cafetiere first then the coffee – hence the name.
- Once the kettle has boiled pour the water into your pre-heated cafetiere.
- Now allow the water to cool to below 95°C. This should take between 45 secs – 1min 45 secs, depending on the size of your cafetiere (a 3 cup size cafetiere will cool quicker than a 8 cup cafetiere as the volume of water in the 3 cup is smaller).
- When the water has cooled, add the coffee and stir slowly until all the coffee is thoroughly saturated. If the coffee is not completely soaked, it will rise up out of the water as it starts to expels CO2. Tip: When the coffee looks all mixed in on the surface, continue to stir another 5 times.
Start stirring
Keep on stirring
Reverse Vs Standard Method
I conducted some comparison tests with both the standard and reverse brewing method using a glass 3 cup cafetiere. From the graph below, you can see how quickly, with the standard method, the cafetiere loses heat. After only 30 seconds it’s already out of the optimum temperature range. Whereas with the reverse method, it stays in range for nearly 2 minutes.
As for taste, when comparing the resulting cups side by side, the reverse method is definitely sweeter. Strength wise, they were both the same. Which is interesting; because of its higher temperature throughout the brew you would expect the reverse method to extract quicker. I assume that this is a result of pouring water over the coffee in the standard method. As well as agitating the grounds, the coffee is also under some pressure (i.e. from the weight of the falling water above it) and this kick starts the extraction.
Still the reverse method is not perfect. Assuming your total brewing time is 4 minutes, then using a glass cafetiere, the brew temperature is only in optimum temperature range for half the time. Maybe it would be better to grind the coffee finer to reduce the total brew time or opt for using a thermal cafetiere.
Tags: cafetiere
