Probably a silly question

Bad Fruit Brewing

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I'm trying one of the zombie dust clones I found but was just wondering how long you recommend leaving in primary. Its been fermenting for 48hours now and I'm going to dry hop tonight with the plan of removing hops after 7 days as per recipe and put into secondary. Does this sound right. Thanks in advance for any help.
 
A lot of people wait and dry hop during secondary. By this time, most of the CO2 release is complete. The thought behind this is that the CO2 may strip some of the volatile hops oils and take them out of the beer.

I do not believe that I have seen any data on this other than various anecdotal evidence.

Also, if you have a good primary fermenter, many people now forego secondary fermentation altogether. I quit several years ago. This eliminates additional opportunity for oxidation and outside infection from non-desired organisms.
 
A lot of people wait and dry hop during secondary. By this time, most of the CO2 release is complete. The thought behind this is that the CO2 may strip some of the volatile hops oils and take them out of the beer.

I do not believe that I have seen any data on this other than various anecdotal evidence.

Also, if you have a good primary fermenter, many people now forego secondary fermentation altogether. I quit several years ago. This eliminates additional opportunity for oxidation and outside infection from non-desired organisms.

Thanks for that. I had seen that there are quite opposing view's on dry hopping during and after fermentation and really wasn't sure which way to go. I've got a fastferment conical so when I say secondary I mean after removing most of the rubbish via the bowl and dry hopping using the bowl, so very little oxygen. I think ill leave it a week then dry hop for a week then straight into the keg.
 
There is a chemical response that happens when you hop during fermentation, it is called biotransformation.
This is part of what is responsible for the haze, and in big part what is responsible for the big juicy flavors you are going for with the Zombie Dust. In case you missed it, I brewed a very similar "inspired by" on Saturday. I hit it with dry charge one Sunday morning, and dry charge two this morning.
Here is an excerpt from an article on brewing a hazy (which is what the zombie dust is).

Dry hopping during active fermentation takes advantage of a process called biotransformation. What this means is that the yeast fermenting the beer transform compounds in hop to slightly different compounds. This in part helps to draw out those intensely fruity and juicy aromas and flavours we want. After this initial dry hop, I like to dry hop again either in the keg or a few days before bottling to really bolster the aroma.
 
I'm slowly reducing the length of my dry hops. Currently I'm doing around 3 days. It largely depends on the type of hops you're using but for some you start to hit a point where the more vegetal or tannic flavours hit taste thresholds at around 4-5 days.

And if you want a bit more technical depth, there's a bunch here - http://scottjanish.com/a-case-for-short-and-cool-dry-hopping/
 
There is a chemical response that happens when you hop during fermentation, it is called biotransformation.
This is part of what is responsible for the haze, and in big part what is responsible for the big juicy flavors you are going for with the Zombie Dust. In case you missed it, I brewed a very similar "inspired by" on Saturday. I hit it with dry charge one Sunday morning, and dry charge two this morning.
Here is an excerpt from an article on brewing a hazy (which is what the zombie dust is).

Dry hopping during active fermentation takes advantage of a process called biotransformation. What this means is that the yeast fermenting the beer transform compounds in hop to slightly different compounds. This in part helps to draw out those intensely fruity and juicy aromas and flavours we want. After this initial dry hop, I like to dry hop again either in the keg or a few days before bottling to really bolster the aroma.
Good information. I have always brewed pretty clear beers, but have always waited for fermentation to complete before dry hopping. The good thing is that is what I was shooting for.

I might need to do a little experimentation.
 
There isn't a lot of science behind biotransformation FYI. As in no real studies done, but lots of people making claims about it.

Personally I throw my hops in early so that any O2 I introduce gets scavenged by the yeast.
 
If the early addition of hops provides extra oxygen would adding them possibly help a slow fermentation?
 
There isn't a lot of science behind biotransformation FYI. As in no real studies done, but lots of people making claims about it.

Personally I throw my hops in early so that any O2 I introduce gets scavenged by the yeast.

There's a fair few studies done about biotransformation and what they keep showing is that it is real, but people keep claiming it happens in scenarios where it doesn't. Basically only some of the hop oils can be changed and only a subset of yeast produce the enzyme that can make the change.

And it's now looking likely that many of the effects attributed to hop oil biotransformation were actually related to other substances in hops that are also changed by yeast enzymes during fermentation. The trendy one at the moment is thiols. There's a bunch of science being dragged over from the wine world on the ways that yeast can change thiols to provide specific flavours. They've been using bioengineered yeast to push certain flavours for over a decade.

Thought I should post at least one link - https://onlinelibrary.wiley.com/doi/full/10.1111/j.1567-1364.2003.tb00138.x
 
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I'm slowly reducing the length of my dry hops. Currently I'm doing around 3 days. It largely depends on the type of hops you're using but for some you start to hit a point where the more vegetal or tannic flavours hit taste thresholds at around 4-5 days.

And if you want a bit more technical depth, there's a bunch here - http://scottjanish.com/a-case-for-short-and-cool-dry-hopping/

I’ve started dry hopping for 48 hours at 35f after crashing for a couple days. There was a study that said length and temp is pretty is pretty arbitrary.
 
Another silly question, what's the recommended time scale for this zombie dust. Looks like fermentation has finished already and I don't have any way of cold crashing at the moment.
 
There's a fair few studies done about biotransformation and what they keep showing is that it is real, but people keep claiming it happens in scenarios where it doesn't. Basically only some of the hop oils can be changed and only a subset of yeast produce the enzyme that can make the change.

And it's now looking likely that many of the effects attributed to hop oil biotransformation were actually related to other substances in hops that are also changed by yeast enzymes during fermentation. The trendy one at the moment is thiols. There's a bunch of science being dragged over from the wine world on the ways that yeast can change thiols to provide specific flavours. They've been using bioengineered yeast to push certain flavours for over a decade.

Thought I should post at least one link - https://onlinelibrary.wiley.com/doi/full/10.1111/j.1567-1364.2003.tb00138.x

That's a better explanation of my point. There are things happening, but in typical home brewer tradition we're piling on a ton of anecdote and cargo cult in addition to the real science.
 
I am not trying to pretend I know anything on the matter... But I remember coming across an article on the subject in BYO magazine. If you have a digital membership you can reference it online... I tried reading it but am not really into "hops" yet alone the very science heavy write-up on the matter so - I never really finished the article or understood much of what I read... The Article was called: "Biotransformation - Yeast: the empress of fermentation and her majestic biotransformation" May-June 2020 issue.
 
Scott Janish's book said much the same thing.
 
Another silly question, what's the recommended time scale for this zombie dust. Looks like fermentation has finished already and I don't have any way of cold crashing at the moment.
Time is largely dependent on the yeast, not the recipe. If you are getting the same gravity over 3 days, then it is done.
 
This is a good article on biotransformation:

https://www.goodbeerhunting.com/blo...-understanding-hop-compound-biotransformation

I remember being blown away by the Cloudwater DIPA versions they talk about. I did a split batch recently where one was double dry hopped including under active fermentation and the difference with the one that was just dry hopped Just before cold crash was more than I expected.
Really good article. Very readable and still gives some depth on the science.
 

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