Final Gravity 1.020, OK to bottle yet?

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Farpin
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Final Gravity 1.020, OK to bottle yet?

Post by Farpin »

I'm a brew greenhorn. Second 5 gal. batch of what is supposed to be Snow Cap.

When I took my final gravity last week (after the 1-2-3 rule of thumb) it was higher than I expected. Local brew shop noted I forgot to add the amylase enzyme with the yeast and suggested I add it now, mix the crap up at the bottom of the carboy, and check it again in a few days. I did as suggested 6 days ago; just checked and now it is 1.021, with a slow but steady airlock bubble going (no foam).

Given the situation, is this FG to be expected or should it be a concern? and
when should I consider bottling (how long does the amylase enzyme and reactivated yeast need)?
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slothrob
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Snow cap and amylase

Post by slothrob »

It looks like Snow Cap Ale has an FG of about 1.015.

Did the shop say how to stop the amylase enzyme? I've never used amylase after the boil. I'd think it would bring the beer down close to 1.000.
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Farpin
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Post by Farpin »

The shop suggested the amylase enzyme would break larger sugar chains into smaller chains. Once broken down the yeast would then be able to do its magic on the smaller sugar chains.

I assumed, like the yeast, the enzyme would go dormant when it ran out of things to do. It was also my understanding from the recipe, the enzyme was supposed to be added with the yeast; after the boil.

I'm going to let it sit for a while until the yeast settles down and my airlock stops, then bottle.

BTW had a few sips and it tastes great.
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slothrob
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amylase

Post by slothrob »

Yes, that all fits my understanding of amylase, but what prevents it from breaking down all the large sugars into small sugars digestable by the yeast?

The big concern I have is that you will bottle the beer and the amylase will continue to slowly break down complex sugars into small sugars. Then, the yeast will eat those sugars and over-carbonate the beer. That could lead to exploding bottles, or "bottle bombs". This can be dangerous, so watch for signs that the bottles are becoming over-carbonated (gushing bottles, beer glasses full of foam) and be prepared to deal with them before they become a hazard.

I have to make it clear, though, that I'm making suppositions here because I don't have any experience with adding amylase after the boil. This is not a standard brewing practice, so I don't know any other brewers who have experience with it either.
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Farpin
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amylase

Post by Farpin »

Thanks for the heads up. I'll keep a lookout for over-carbonated bottles. I keep them in an enclosed bathtub - just in case.

I'm hoping once the sugars have been converted by the enzyme and consumed by the yeast, the yeast will go dormant and it will be safe to bottle. I just don't know how long this will take or if it will have any impact on the flavor. I took a sip from the gravity tube and, at least for now, it taste good.
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