Why coffee needs to ''rest'' before making espresso - Page 4

[luca]

+ syrupy
+ tigerstriping and speckles in the crema
- Very very very sour
- extraction starts all crema but the crema dissipates very fast and a couple minutes after the extraction the crema has reduced to about 1mm and can't support a spoonful of sugar anymore
- crema contains very large bubbles

Are these typical signs of beans that are too fresh or is this a quality of this particular roast (especially the sourness which is simply unbearable if it remains this way)? The extraction ran for 25secs and gave about 40ml or 1.3oz.

Yep, all typical. Except for it being syrupy; usually it would be a bit more watery. Tiger striping and speckles are sometimes said to be due to the grinder, not the coffee.

[Merlino]

Thank you very much for the reassurance! This is the first time I've bought beans that were this fresh. Normally my beans via the mail are about 2-3 days old when they arrive...

[HB]

Are these typical signs of beans that are too fresh or is this a quality of this particular roast (especially the sourness which is simply unbearable if it remains this way)?

Yes, especially the fast dissipation of the crema. You could raise the temperature to address the sourness, or wait until the coffee has degassed for 3-4 days. The peak period varies among coffees. For example, Tony recommends 5-7 days post roast for his Caffe Fresco blends and Intelligentsia recommends 3-4 days.

[Merlino]

Thank you! The coffee is gradually becoming less sour but the crema is still gone within a matter of seconds if I pull two singles from a double basket. Takes a bit longer if I pull one double with the same amount of coffee...

[oregonbarista]

I have noticed that there is a huge difference in our espresso between fresh roasted and having let it rest for a few days. We use the Sweet Espresso blend from Longbottom in Oregon.

We have it delivered fresh every Wednesday from the roaster. Using fresh beans the extractions blond early and are full of dissolved CO2 gas. The crema dissipates very quickly due to high levels of carbonic acid in the shots. The acidity greatly overwhelms the sugars in the espresso. We also have to use a finer grind with the fresh espresso to control the flow rate.

After 2-3 days of resting and degassing the shots are alot darker and flow evenly. The crema is alot tighter and remains for a long time. It seems without so much carbon dioxide being dissolved alot more solids from the coffee are getting dissolved giving a longer lasting crema and fuller body. The espresso tastes much sweeter as the caramalized sugars are not overwhelmed by carbonic acid. The grind for our rested espresso blend is also a bit coarser.

Obviously we and our custys prefer rested and degassed espresso beans. We go thru our entire stock in 7 days and even on day 7 the espresso is still flowing dark and syrupy.

Hopefully this helps someone as for the longest time we could never figure out why the fresh beans tasted so sharp and acidic. The crema was very thick but dissipated very quickly. We were stumped. Now we know the chemistry behind it.

[LeoZ]

Yesterday I roasted a Brazil/Sum/Uganda blend. About an hour afterwards I pulled a couple espresso shots with it.

For the first shot, I let the grounds sit in my Mazzer Mini for two minutes before dosing/distributing/packing. The shot had an eye-watering bitter grapefruit front end. It was hard to take.

I let the grounds sit for six minutes before preparing the second shot. It was a lot better. The grapefruit was still there, but the flavors had rounded out a bit and included marzipan and light roasty notes.

Based on this testing, i'd say that a 11.45 minute rest period would have hit the sweet spot with this coffee.

what do you roast to?

im typically in the FC+ range.

i think this depends a lot on the beans, and the roast. i try to sample most of my roasts on the first day just for a flavor profile. from my experience, most espresso blends (ive been having greenline, classic italian, and a home-made blend) are a little too bright in the first 2-3 days for me. then again, i prefer these blends to sit a bit, it seems to bring out more caramel and chocolate.

what i have noticed, is that a more earthy or chocolaty SO bean, lets say a sumatra or a daterra, roasted to a FC+ or a vienna, is perfectly drinkable as espresso on the first day. ive actually roasted some beans that were good for only the first 2 days, then were undrinkable, too bitter.

[LeoZ]

im not sure i buy it when coffee is compared to wine or beer, especially regarding aging.

cheese is a food, and it can be aged, but when cheese is aged, the cheesemaker deliberately allows mold to form on the outside to control it. controlled spoilage is how i look at cheese.
meats (prosciutto and sausages) are different as they are dried as part of the aging, but, again, 'spoilage' is part of the aging process.

these are the only food examples off the top of my head that require 'aging'.

beer and wine are completely different in my opinion. without aging, they wouldnt exist. you need time for the sugar to ferment. ok, they peak, but they still require aging first. so, why age coffee? i dont age my chicken. :p


my point - outgassing, for an hour, or a day, isnt aging, so dont compare it to a fermentation process!

outgassing is more like allowing the turkey juices to set in after roasting. it is just the end of the cooking process and in some cases, will produce a better taste after a day or so. (yum leftovers!) coffee (ie, food) doesnt require aging. the cooking is done when you turn off the roaster.

Leo
(i wonder if i can ferment a roasted coffee?)

[AndyS]

what do you roast to?

im typically in the FC+ range.

Holy cow, Leo, you're replying to a post of mine from over a year ago.

I try and roast as light as I dare, but I rarely dare any lighter than first pops of 2nd. I also try and put a significant quantity of bright beans in my blendz, and they just seem to take a few days to get any good.

[LeoZ]

Holy cow, Leo, you're replying to a post of mine from over a year ago.

I try and roast as light as I dare, but I rarely dare any lighter than first pops of 2nd. I also try and put a significant quantity of bright beans in my blendz, and they just seem to take a few days to get any good.

sorry, i saw this thread at the top of the list.. just started reading!