Amylase Enzyme how much to use

[ChrisKennedy]

Can unconverted starches increase a gravity reading?

Because amylase enzyme can't work on sugars, right, just starches?

So there would never be a threat of amylase enzyme making a thin beer like Beano would, since it isn't touching the dextrins that won't ferment, just any unconverted starches that happened to be left over from an inefficient mash.

[ajdelange]

Can unconverted starches increase a gravity reading?

Yes, soluble ones and small particles (i.e. small enough that they are displaced along with the fluid displaced by a hydrometer) will increase the gravity reading.

Because amylase enzyme can't work on sugars, right, just starches?

What's the difference between starch and sugar? Just the size of the molecule so yes, amylase can effect sugar. This particular product (see Crosby and Baker's web site), however, does not lyse 1-6 linkages, just 1-4 so it does leave the dextrines. You should not get an overy thin beer for this reason.

So there would never be a threat of amylase enzyme making a thin beer like Beano would, since it isn't touching the dextrins that won't ferment, just any unconverted starches that happened to be left over from an inefficient mash.

Essentially. alpha-Galactosidase (the enzyme in Beano) can break 1-6 linkages. C & B's amylase cannot.

[ChrisKennedy]

I am not a chemistry guy, so could you explain a bit more about amylase enzymes and their effects on various sugars? If they can't touch dextrins, can they touch anything shorter? Anything smaller than amylopectins?

[11amas]

Here is a good thread on the subject: viewtopic.php?f=6&t=11988

[greggor]

Thanks all for the excellent advice. I chose the amylase enzyme over beano so the beer wouldn't over attenuate. I first raised the temp of the ferment to 80 F then added half the recommended amount of B&C enzyme (1/2 teaspoon) waited 24 hours and added a healthy dose of WLP 01 that I harvested and washed from a my last beer. made a starter (using the same wort from the original batch that I had canned) oxegenated the starter real good and pitched when the starter was at high krausen, 24 hours later I have a very active fermentation again with a thin Krausen head on top of the carboy. So far this method seems to have unstuck my fermentation. Hoping this one will finish around 1.010-1.008. I'll report back in about a week.

[Cambrinus]

How did you get on? Did the gravity ended up at what you expected, 1.010-1.008?
Is it still fermenting? Did the beer over attenuate?

Sorry for all these questions but I've been following this threat with big interest. I made the mistake of mashing on too high temp and now I have a stout which is stuck at 1.020.
I am thinking of making a priming solution, cool it, add a quarter teaspoon of Amylase. Poor this into a secondary and rack my stuck stout on top.

My biggest worry with adding Amylase to a secondary is that I end up with a very thin, over attenuated, undrinkable methanol tasting liquid.

[greggor]

Ok after 10 days the wort dropped from 1.022 to 1.016 on my golden strong so it didn't get down to the 1.010 I was hoping for. I still have the other batch (trippel) in the fermenter I'll have to check the gravity this weekend as its now been almost a month since I added a half teaspoon of enzyme to each (half the recomendation on the label). Overall I would say it was a success. I bottled the Golden strong 2 weeks ago Sunday, I'll be cracking one this weekend and I'll check the gravity again to see if it came down any lower than 1.016. When I sampled it during the bottleing it tasted great no thin and no off flavors. Maybe next time I would add a whole teaspoon of enzyme.