Wednesday, April 30, 2008

Time to brew

I am very busy this time of year, but the yeast starter bubbling on my kitchen counter will force me to brew tomorrow.

Yesterday, I made a yeast starter using some Wyeast 1056 (American Ale) that I had harvested from a different starter 2 months prior. I had it stored in a capped bottle in the back of my fridge. It woke up rather nicely. The bubbling is consistent. A swirl every now and then rouses the yeast and keeps everything moving. I should have a very nice stock of yeast to pitch into my wort.

I am going to brew my standard Metathesis Ale. It is a simple American Pale Ale made with an excessive amount of cascade hops. Cascade hops are currently hard to find. I have about 8 ounces in my freezer. I have had them for a while, so they need to be used.

The last time I made this beer, the product had a distinct grapefruit aftertaste to it. Since I'm a fan of grapefruit, I enjoyed this. I assume this was the result of some esters formed during fermentation. Over time, this flavor faded and became less noticeable.

4 comments:

the indefatigable mjenks said...

I guess you could always stir in some esterases during the course of the fermentation if you're that worried about it. Mmmmm...protein-y beer.

milkshake said...

There are some monoterpenic thiols actually used as grapefruit flavoring - they are extremely potent but oxidise easily. It would explain the fading-away effect.

Chemgeek said...

Really??!! I gotta look into that. I've never thought of anything related to a terpene and much less a thiol as having a pleasant taste or aroma.

the things one learns by having a blog....

milkshake said...

1-p-Menthene-8-thiol, see

http://www.givaudan.com/givcom/jsp/channelViewUtil.jsp?channel=Ingredients/Flavour/Products

Also menthenone-8-thiol has a black-currant notes and there are several other thioether-esters with fruity characteristics. Whereas the furane thiols have very strong Starbucks-like French Roast coffee roasted flavor. There are many other thia compound that have pleasant meaty broth-like flavor. The thing about these flavorful thio compounds is that they are ridiculously potent and in concentrated form smell awful, only once you get down to ppm levels and mix them with other stuff they become nice.