Coffee Quantity vs Grind Size for Extraction Time

#1: Post by **bgm1911** » January 12th, 2016, 4:32 pm

Unfortunately, I just received my replacement K30, with only having the first one for 2 weeks, and now will have to start all over.

Changing either grind volume (as weighed with a scale), or the coarseness, it appears to me (after dozens of sink shots) that there has to be a point where the coffee volume plays a large part in the extraction time.

Example 1: grinder set to 5 coarseness, and weight ground is 16g = 25sec extraction time
Example 2: grinder set to 6 (coarser than 5), and the weight ground 18g = 25 sec extraction time

Because neither of these will produce a drinkable shot, how do I determine which grinder parameter I should be adjusting?

It doesn't help that I have the flu trying to do this!

#2: Post by **yakster** » January 12th, 2016, 4:37 pm

Start with your target weight for your coffee (16 g, 18 g) and adjust the grinder for the optimum extraction time. Once you have it dialed in, you can compensate for day-to-day variations by varying the weight of coffee that you use if you prefer, instead of changing the grind size but you should start with your preferred weight (ensuring that this gives you adequate headspace for your espresso machine) and adjust the grind.

#3: Post by **Double Shot** » January 12th, 2016, 4:47 pm

You would need to figure out if your shot is over extracted (bitter/ashy) or under extracted (sour/acidic).
Once you have that info you can either tighten the grind (if it's under extracted) and lower the dose, so you remain within the 25 - 30 sec window or loosen the grind (if it's over extracted) and raise the dose. The trick is to find a happy medium. Brew water temp also plays a part (cooler water will enhance the acidic properties and hotter water the bitter) but it pays to alter one parameter at a time initially. another_jim has written an awesome thread somewhere on here about this. It will be in the FAQ's or Espresso Newbies section. Your flu may not be helping with taste diagnosis though...

#4: Post by HB » January 12th, 2016, 6:26 pm

bgm1911 wrote:...how do I determine which grinder parameter I should be adjusting?

Most baskets have a recommended dose. The stock baskets for Quickmills work well with 16 grams; above 18 grams you risk crashing the puck surface into the dispersion screen. Have you read Espresso 101: How to Adjust Dose and Grind Setting by Taste? It offers good advice.