Hi,

My name is Sebastian and I own a coffee bar in Cartagena, Colombia. I've been in this community for not so much time, nevertheless I love how everyone is constantly helping members with differentes issues/questions. This thread is about something weird that happened to me 4 days ago. I've been searching for the "perfect espresso" since we opened, and boy, we've done pretty awful espressos at the beginning. Over the course of some months we were achieving better results. So, what happened is that we were pulling espresso shots as usual, but out of the blue the extractions were almost perfect. I mean, perfectly balanced sweet, full bodied and rich espressos. We didn't change any setting at all. Everything was just how it was, except the espressos changed from regular to exquisite without any modification in the grinder and machine.

The next day, we opened as usual and left the settings of the grinder the same, and for the machine too as well. Unfortunately the espressos weren't as good as the day before but they were relatively close. The grinder was now dosing 20.5 grams (Mythos one grinder) of coffee whereas the day before, using the same configuration, the grinder was dosing 17.3 gr.

Our real question is this: ¿How is it possible that the grinder started to dose WAY higher under the same configuration (same coffee, same machine, same EVERYTHING)? ¿Why was the extraction good for 1 day and the next day was just horribly off?

The only variable that really changes drastically over the day is the A/C of the place. We are located in a hotel's lobby, therefore is difficult to maintain the same temperature over the course of the day.

Please feel free to comment!

I am not a pro or anything, but this happens with coffee. Humidity, temperature, fate will affect your grind. That's why HBers always advocate dosing by weight, and not by time. Your dose has increased in the meantime, so probably your shots are underextracted?

I have no experience with your grinder in particular, but changes in ambient conditions throughout the day effect grinding behavior for sure. If temperature and/of humidity increase, the grind setting usually has to be tightened to produce the same yield of espresso in the same amount of time. I imagine that this might affect the dispensing flow rate of the ground coffee as well. Keeping the timer setting constant could then result in dosing variations, though to go from 17 to 20 grams overnight seems like a lot to me. Workflow-wise to regularly weigh the dose prior to pulling a shot takes some getting used to, but it Will be good for consistency.

As a test you can adjust your timed grinder three times a day (morning, lunch and dinner) to achieve your desired weight based on time knowing that factors such as humidity effect weight of grind from a timed grinder.
If the time vs weight is dramatically off you can adjust more often and if it steady throughout the day you can adjust less often.
I also have a timed grinder but being in a home setting I find it more steady. Curious to know your feedback.

@dillin and @DeGaulle I always weigh my shots because its the only way to be consistent with the product. Just rather weird I got such a change in the dosing system of the grinder. I actually searched the wheather conditions to check out of something changed drastically over the day. I know that climate factors will utterly change the grind settings and therefore extraction, but I never thought it would change 3 grams under the same dose configuration.

Anyways, thanks for the help. I will let you guys know what happens in these couple of days.