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Squatchy
11-24-2014, 07:51 PM
Hi

I'm not sure yet what the correct language is as I am very new here but I have some questions. My understanding is if we pitch a yeast in an OG higher than 1.1 or so we stress the yeast because to much atmospheric pressure. See I don't know what we call atmospheric pressure. In any case if I understand what I'm reading it's the pressure on the cell walls that stresses out the yeast. Is this correct?

Assuming this is the case. And if I understand more reading. Why then when we are making a melomel we make the must with honey addition to 1 or 1.1 and then top it off with many pounds of fruit. Isn't that now putting to much stress on the yeast and causing unwanted fusels??? Or is fruit sugar weight not the same as honey sugar weight?

So if this is true wouldn't we do better to step feed the fruit into our batch? So as not to squish the yeast?

In a same, but different scenario if we step feed either with fruit or with honey ( or any other type sweetener) do we then calculate the rise and drop of each new step to get the total of dropped metric to determine the ABV. In other words is it the combined total of dropped points that determine the ABV?

I hope this makes since. I still can't figure out how to use a calculator to know how to "supposedly" know where we end up. I say "supposedly" because it's my understanding that just because a yeast is supposed to pass out from a certain amount of alcohol doesn't mean they will because you can train the little bastards to become alcoholics and increase their tolerances to alcohol :) And they can then not pass out until they have finished 3 40's instead of just two :)

Just playin here a bit but it makes my point clear! At least if you follow my presentation it should seem clear.

I want to make a BOMM melomel and don't know when to add fruit, how much and how to count it in my ABV calcs. Seems like it's somewhat split as to add pre, or post fermentation, or a combined. I'm wanting to understand this so as not to produce the dreaded fusels?

Lastly I can't get enough clear info on pectinaze and fruit. Such as how much, when and why. I guess I would now have to add in there ph levels as well... It just goes on and on and on in my head. I know tons more than I did 3 weeks ago and yet I'm still pretty much paralyzed with too many gaps in my science.



I think that normally, if you ask too many questions in a thread, many remain unanswered. Hopefully you could answer down the line one at a time so I can make sense of things and still not have gaps in my understanding before this thread dies out.

Thanks

Ryan

loveofrose
11-24-2014, 08:39 PM
Hi

I'm not sure yet what the correct language is as I am very new here but I have some questions. My understanding is if we pitch a yeast in an OG higher than 1.1 or so we stress the yeast because to much atmospheric pressure. See I don't know what we call atmospheric pressure. In any case if I understand what I'm reading it's the pressure on the cell walls that stresses out the yeast. Is this correct?

Assuming this is the case. And if I understand more reading. Why then when we are making a melomel we make the must with honey addition to 1 or 1.1 and then top it off with many pounds of fruit. Isn't that now putting to much stress on the yeast and causing unwanted fusels??? Or is fruit sugar weight not the same as honey sugar weight?

So if this is true wouldn't we do better to step feed the fruit into our batch? So as not to squish the yeast?

In a same, but different scenario if we step feed either with fruit or with honey ( or any other type sweetener) do we then calculate the rise and drop of each new step to get the total of dropped metric to determine the ABV. In other words is it the combined total of dropped points that determine the ABV?

I hope this makes since. I still can't figure out how to use a calculator to know how to "supposedly" know where we end up. I say "supposedly" because it's my understanding that just because a yeast is supposed to pass out from a certain amount of alcohol doesn't mean they will because you can train the little bastards to become alcoholics and increase their tolerances to alcohol :) And they can then not pass out until they have finished 3 40's instead of just two :)

Just playin here a bit but it makes my point clear! At least if you follow my presentation it should seem clear.

I want to make a BOMM melomel and don't know when to add fruit, how much and how to count it in my ABV calcs. Seems like it's somewhat split as to add pre, or post fermentation, or a combined. I'm wanting to understand this so as not to produce the dreaded fusels?

Lastly I can't get enough clear info on pectinaze and fruit. Such as how much, when and why. I guess I would now have to add in there ph levels as well... It just goes on and on and on in my head. I know tons more than I did 3 weeks ago and yet I'm still pretty much paralyzed with too many gaps in my science.



I think that normally, if you ask too many questions in a thread, many remain unanswered. Hopefully you could answer down the line one at a time so I can make sense of things and still not have gaps in my understanding before this thread dies out.

Thanks

Ryan

Okay. Lots of questions here, so let's go by numbered paragraph so I don't get lost.

1. Osmotic pressure, not atmospheric pressure. In the case of honey, there is a very low moisture content and a high sugar content. Honey doesn't spoil because all the water is sucked out of micro organisms due to osmosis. If sufficient water is added (<1.12), the osmotic pressure is reduced enough to make fermentation possible.

loveofrose
11-24-2014, 08:43 PM
I had a huge post and it got cut off at paragraph 1. I will try to redo it now.


Better brewing through science!

loveofrose
11-24-2014, 08:53 PM
Fruit has some sugar, but not nearly as much as honey. It also has water and nutrients. Generally, 2-4 lbs of fruit are used per gallon depending on if you want a hint of fruit or a massive fruit flavor. If you start with a good nutrient schedule and buffer the pH (like in my BOMM recipe), you won't have any problems with fusels. I use 1/2 tsp pectinase per gallon and it has never failed to clear.


Better brewing through science!

skunkboy
11-24-2014, 11:12 PM
And you should now lots more three weeks from now :)

+1 for loveofrose's response

Squatchy
11-25-2014, 08:48 AM
I had a huge post and it got cut off at paragraph 1. I will try to redo it now.


Better brewing through science!

I'm sorry you lost all the hard work with your disappearing post. I too spent a good long time replying to your last reply on PM and when I sent it to you it didn't go through and I couldn't retrive it either.