Extraction is a dense topic...
and this experiment may lift off a bit of that density. It will provide some answers, depending on how you feel about my scientific methods, or in some peoples views, lack thereof. Armed with an idea, a refractometer, and two bags of the same coffee I decided to dig in to the topic of if bean temperature and extraction percentage are in any way linked. I took both bags and split them into three different categories. One category would be kept at room temperature, another will be heated in the microwave, and the final would be frozen.
Each coffee type was dialed in to a very similar shot time and output to minimize the differences between each of category. The shots included in the testing results are all within the following recipe: 18 grams of ground coffee in, 40-41 grams of espresso yield out, in 24-25 seconds. Testing was conducted using nine bars of pressure and water set to 200 degrees Fahrenheit. Seven shots within each category met the standards for testing, and one additional shot was pulled for tasting purposes.
The results of this experiment were pretty surprising. Although, I didn't really have any real expectations about what I would find. I don't want to spoil the entire experiment though, so hit play on the video and make your way down the rabbit hole of bean temperature and extraction.