I have been making pourovers using Peet's decaf house blend (pre-ground). It makes an amazing cup of coffee 75% of the time. However, I have noticed that when it does not turn out so well, it is because it failed to bubble up when I initially wet the grounds.

I am doing the pourover the exact same way every day, and using a water kettle with the temperature set to 210 degrees. I let it sit for about 20 seconds after it boils, then I pour. Assuming the conditions (coffee amount, water temp, and my method) are the same every day, what would cause the larger bubbles to not form on approx. 25% of my pourovers? This has me very perplexed and frustrated.

Thanks for your help.

Let's assume you're talking about blooming.

The bubbling is caused by degassing. If the beans are past their prime, there will be no degassing, so blooming will be a pointless procedure. If you don't see any bloom and only large bubbles coming to the surface, those are just trapped airpockets making there out of the brew. This generally doesn't happen with fresh coffee that blooms properly.

Agreed. My wife only drinks decaf and I've found that decaf coffee generally stales faster than regular coffee, which makes sense when you think about the additional processing involved. That being the case, if you shop around you can find decaf coffees that are nice and fresh-and you'll know it when you find it by the vigor of the bloom. You can also avoid premature staling by grinding to order rather than buying pre-ground coffee.

kewpcg wrote:I have been making pourovers using Peet's decaf house blend (pre-ground). It makes an amazing cup of coffee 75% of the time. However, I have noticed that when it does not turn out so well, it is because it failed to bubble up when I initially wet the grounds.

I am doing the pourover the exact same way every day, and using a water kettle with the temperature set to 210 degrees. I let it sit for about 20 seconds after it boils, then I pour. Assuming the conditions (coffee amount, water temp, and my method) are the same every day, what would cause the larger bubbles to not form on approx. 25% of my pourovers? This has me very perplexed and frustrated.

Thanks for your help.

Get yourself a grinder... The beans were probably fresh at the time they were ground.

+1. Pre-ground coffee is inherently stale, since grinding greatly accelerates the staling process. Get yourself some freshly roasted beans from a good roaster, and get a good quality burr grinder. You will notice a huge difference not only in the bloom of the coffee, but also and much more importantly, the flavor.

Thanks everyone. I know... buying pre-ground is not ideal. We always used to grind and brew our pot of coffee fresh each morning, but that was before I switched to decaf. I don't want to mess with the noise and hassle of grinding if at all possible, especially now that I have had great results with Peet's house decaf, for the most part. (I keep it in the freezer too, but I'm sure that doesn't help much.)

The thing is, one day the pourover results in marginal tasting coffee and the next day it comes out perfectly. This is with the same bag of Peet's pre-ground, same method and temp. I'm just trying to figure out if there is some very subtle variable I'm overlooking. On the days it turns out bad, it's almost as though the coffee grounds are repelling the water when I pour it in. When it "sinks in" and a few air bubbles percolate up, it tastes much better. I'll keep and eye on things and let you know if I figure it out.

I know I was happy with the taste of a bag of fresh ground coffee purchased from Intelly when we were visiting in Chicago. On such occasions that I must use preground, I store it packed fairly tight and bag folded down to keep air away from the grounds. And I used it within one week. But you find a difference day to day, not just after the bag has been open a few days. Perhaps something about how you settle the grounds in the filter?

I think Chert is onto something... I've seen stirring used in pourovers, could that be something to try to mix better?
I also noted that tapping my Kone to settle the grounds had a similar sounding repelling effect, so is it possible that some of the grounds are compacted? I seem to recall way back when, that freezing pre-ground tended to make it clump/compact...so maybe a stir of the dry grounds might loosen them up a bit...
Best of luck!

Hmmm, a new twist... Considering the grounds are coming out of the freezer, are the grounds the same temp before each pour?

kewpcg wrote:On the days it turns out bad, it's almost as though the coffee grounds are repelling the water when I pour it in. When it "sinks in" and a few air bubbles percolate up, it tastes much better. I'll keep and eye on things and let you know if I figure it out.

This is why some pro baristas make a well in the center of the coffee before they start pouring, so the water can find a way easily into the bed of coffee. In regards to bloom, getting more bubbles, more expansion etc. this is actually related to the carbon amount. Simply explained, water in, Oxygen in, Carbon out = more fizz
The carbon trapped inside the beans during roasting would escape faster due to enlarged surface area of pre-ground coffee. You should seriously consider buying freshly roasted beans and grind on spot. Opening a well in the center and buying fresh beans, grinding fresh will resolve your problem since you say all other parameters stay same for each brew. Also, I would not suggest keeping pre-ground coffee in refrigerator due to humidity. Both beans and pre-ground coffee gets affected from the humidity. If you insist on buying pre-ground, then divide them into equal portions and keep each portion in mini zip-locks, try not to leave air inside, zip and keep them inside a box or something where it won't have any contact with light and heat/cold. Use 1 portion at a time. Keep the empty zip-locks and re-fill next time you buy from Peet's. This way you would still be consuming stale coffee regardless, but considerably less stale. Also it could be a better practice if it is possible to buy pre-ground only 1/2 lb at a time. Alternately you can buy 1 lb beans and ask Peet's to grind half of it for you. Later on you can take the other half there and ask them to grind remaining beans. I don't think they would object to it as long as you keep buying coffee from them