Convertase 300

[NewWestBrewer]

I have read several threads about using enzymes to help with stuck fermentation. I have some liquid Convertase and was wondering if anyone knew the recommended dosage per gallon. I have searched the net but only found one guy saying anywhere from .08ml to 0.28ml / gallon.

Thanks

 

[SpaceManBrew]

Yikes. I personally am not a fan of breaking down the sugars in a stuck ferm... Just like adding beano... IMO I wouldn't add alot, I haven't used the stuff but I do know that it will eat till its gone. You might finish below 1.000, pretty easily. You will dry out the beer pretty fast. I wonder if anyone else has more experience with it... But thats all I have.

You think about re-pitching?

What are you stuck at?

 

[day_trippr]

I found a different guy (here) that says 1 liter per 15-30 barrels.

Worked out the math and indeed on the low side he's at .088 ml/gallon, double that on the high side. That's crazy small amounts. I'd round up to a half milliliter or one milliliter for a five gallon batch and call it done...

Cheers!

 

[pjj2ba]

I don't think these products are really designed to unstick a stuck fermentation. These enzymes break down more complex sugars into simple ones for the yeast to use. However if your yeast has crapped out, having more simple sugar around (more than was already in the stuck ferment) is not going to magically wake up the yeast. By analogy, that would be like going up to someone who has just stuffed themselves with food until they can't eat anymore, and then offering them another plate of food.

They are good for high gravity beers, (and light beers) when properly used. For a big beer, rather than adding extra sugar part way through the fermentation (so the starting gravity is not too high and keep the yeast happier) you can add the enzymes to get more sugars for the yeast to eat - as long as the yeast are still eating

 

[NewWestBrewer]

I don't think these products are really designed to unstick a stuck fermentation. These enzymes break down more complex sugars into simple ones for the yeast to use. However if your yeast has crapped out, having more simple sugar around (more than was already in the stuck ferment) is not going to magically wake up the yeast. By analogy, that would be like going up to someone who has just stuffed themselves with food until they can't eat anymore, and then offering them another plate of food.

They are good for high gravity beers, (and light beers) when properly used. For a big beer, rather than adding extra sugar part way through the fermentation (so the starting gravity is not too high and keep the yeast happier) you can add the enzymes to get more sugars for the yeast to eat - as long as the yeast are still eating

I added under 1 ml for 3 gallons and both are bubbling like crazy again.

 

[pjj2ba]

That is always a question with a "stuck" fermentation - is there no food left, in which case the enzymes can help, or have the yeast crapped out, in which case it won't be useful

 

[NewWestBrewer]

That is always a question with a "stuck" fermentation - is there no food left, in which case the enzymes can help, or have the yeast crapped out, in which case it won't be useful

It looks like the there was still plenty of sugar left as both fermenters were going like crazy again this morning.

 

[helibrewer]

If you have to use enzymes to create more food for the yeast (more simple sugar) then there is something wrong in the mash.

Since adding the enzymes restarted fermentation, the yeast had run out of food which means conversion in the mash was poor. The problem with enzymes is they are very difficult to stop. They will keep chopping up carbohydrate chains until there are no more which can leave the beer without any body. Enzymes are not "consumed" through activity so they proceed until all substrate is gone.

 

[NewWestBrewer]

If you have to use enzymes to create more food for the yeast (more simple sugar) then there is something wrong in the mash.

Since adding the enzymes restarted fermentation, the yeast had run out of food which means conversion in the mash was poor. The problem with enzymes is they are very difficult to stop. They will keep chopping up carbohydrate chains until there are no more which can leave the beer without any body. Enzymes are not "consumed" through activity so they proceed until all substrate is gone.

Yeah we have had a few beers stop fermenting early so we are double checking our thermometers as the only beer that fermented out completely was mashed at 149. All the other that got stuck ranged from 154-157 so I am thinking that maybe the thermometer might be a few degrees higher that it is reading. Does that make sense?

 

[NewWestBrewer]

Well if anyone uses this go VERY lightly on the dosage. I did .0.3ml/gallon and it took both my beers to 1.000!!!!. Samples still tasted ok but next time I will use maybe 0.1ml per gallon.

Live and learn I guess.