help with astringency

[beanless]

I am having problems with astringency in my finished chocolate and assume it is my roasting. The last batch was Peruvian criollo/trinitario beans which I roasted in oven for
5 min at 297
5 min at 255
5 min at 290 (was aiming for 250)
5 min at 250
5 min at 255
5 min at 255
2 min at 250 stirring at rotating top to bottom in oven at each interval.
I think I taste the astringency decreasing or even disappearing during the roasting.
It is not really noticeable after conching (40 hours) but it is definitely there after molding.
After burning a batch am I being to cautious on the times and temps?
Any suggestions?

[Brad]

My experience with astringency tells me that it's directly related to the fermentation (or lack thereof) of the beans, and there's not a heck of a lot you can do, other than a long roast to "toast" the beans more.

When roasting in my home oven, I use 300 degrees F as the baseline to begin with, and don't adjust the temperature at all during the roast.

I do however stir the beans regularily to ensure an even roast.

Then, every few minutes I open the oven door and take a good, deep sniff. You will notice that during the first few minutes, there's almost no smell, to maybe a light brownie smell. Then the smell gets very acidic, and there's a light smoke that is visible when you open the door of the oven.

In time, that smell will change from being acidic, to an amazing "baking brownie" smell.

When there's almost no acidity in the smell, your beans are pretty much done.

Every variety of cocoa beans is different. I have 4 different varieties in my shop, and the roast times range from 30 minutes, right up to 1 hour and 15 minutes.

To address astringency, I would suggest a higher temperature, or a longer roast. Keep in mind however, there will be a point in the roast where there is no longer even a "baking brownie" smell. My experience says not to go beyond that point, or you will in fact burn the beans.

Hope this helps.

Brad.

[FeralOne]

The Peru is my absolute favorite bean right now. After a few batches the one that turned out perfect was roasted at 300 for 25 minutes. I use a 'crisper' baking pan. It's an oval cookie sheet with little holes all over the bottom, and I find that I don't need to open the oven door to stir them so the temperature doesn't fluctuate so much.

The end result of this batch was a sweet bean with a slight fruity flavor and very little astringency.

It seems that Brad and I can agree that 300 is a good roast temp. I know some people will roast at lower temps, but for my oven (which is kind of inaccurate) anything lower will just heat the beans but not roast them, anything higher starts to scorch them.

Andrea

[Brad]

Andrea;

Good point with regard to the perforated pans. We use commercial versions of exactly that in our shop.

Brad

[beanless]

Thanks for the advice all.

I have just returned from holiday and am about to order some more peruvian beans and will try roasting at 300.

With the perforated pans is it just the peruvian bean you found didn't need stirring? Also I use a pizza stone - but would I be right in assuming the perforated pan could not be put on top?

Ali