It’s one of the first things new baristas learn: before making a pour-over, rinse the filter with hot water.
This is supposed to do two things:
- Remove any paper dust that might be imparting a papery taste to your brew.
- Preheat your dripper so that it absorbs less heat from your slurry, resulting in a higher total extraction.
But is it necessary?
In the process of finding the best filter for the Etkin Dripper, I started asking a different question:
Would we be better off not rinsing the filter?
When looking at the risk/rewards of rinsing a paper filter, it’s helpful to consider the filter itself. Paper coffee filters come in a variety of shapes and sizes ( for a deep dive that literally puts paper filters under the microscope, check out this article by Jonathan Gagne ). Depending on the weight of the paper, not to mention if it’s bleached or unbleached, rinsing your filter paper might be more or less necessary. The conventional logic is that thicker filters and unbleached filters require more thorough rinsing.
In the case of the standard basket coffee filters used by the Etkin Dripper, these tend to be lower weights of bleached paper, so already rinsing was having less of an effect.
Having been taught the importance of rinsing filters, I was surprised to learn one of my coffee heroes, Peter Giuliano, advocated skipping rinsing.
Giuliano mostly was speaking from a sustainability standpoint. Filtered drinking water is a finite resource. Heating water requires energy. Why waste resources doing something with minimal effect on cup quality? Giuliano argued the difference between a rinsed filter and an unrinsed filter was practically undetectable in the finished brew. The opinion would be echoed by James Hoffmann, who argues rinsing Aeropress filters makes an imperceptible difference compared to not rinsing.
What are the risks?
Beyond sustainability concerns, rinsing your filter raises the additional question, what if it harms your brew?
Here I am thinking of the standard basket coffee filters that are used by the Etkin Dripper, and practically any consumer autodrip machine. These filters tend to be very thin.
When rinsed, these filters tend to lose their shape and stick to the walls of the brew basket. This loss of airflow can cause the brew to choke. In the case of batch brewers, they can even collapse, causing coffee ground to get in the finished beverage.
Given the potential risks and rewards, I’ve started not rinsing my filters when using the Etkin Dripper and I’ve never been happier with the results.
But what about heat loss?
When we’ve shown our friends in the coffee industry the Etkin Dripper the number one question we’ve received is about temperature stability. I plan on taking a deeper dive into slurry temperature in a future blog post, but now, suffice it to say the point of water temperature is extraction. You need energy to dissolve the soluble compounds.
If you achieved your target extraction and the coffee tastes good, then I’m not worried about slurry temperature.
Of course, you can preheat the Etkin Dripper with hot water before you put in the filter if you really want to— but most mornings I have a simpler solution:
I start brewing with 98° C water— which is technically slightly above SCA standards (92-96° C / 195-205° F) knowing that the dripper and the coffee is going to absorb some of that extra heat.
I’m hitting my target extractions. The coffee tastes great. Mission accomplished.
I know to a certain degree, it’s inevitable. Haters gonna hate. Baristas are going to rinse. But if you’re using a standard basket filter — the sort you can buy in any grocery store — we don’t recommend rinsing.
But don’t take our word for it. Test it for yourself and let us know the results via email or on Instagram.