Help with Amylase

Folks,

A few weeks ago I started a dark ale batch. I had picked up the recipe from my local brew shop.The grain bill was mostly two row with a little Cara Munich and chocolate malt thrown in. The yeast was Wyeast Irish ale yeast. The recipe also called for amylase enzyme.

It didn't make any sense to me that I should have to use it so I asked some of the more experience Brewers in my brew guild for their opinions. They were evenly split as to whether I should use it or not. I decided to split my 7 1/2 gallon batch into a 5 gallon batch and a 2 1/2 gallon batch. I added about 1/2 tsp of amylase to the smaller batch. The results were impressive. The fermentation took off much faster in the smaller batch, and went much further. The larger batch went from 1074 to 1010, which was exactly on target. The smaller batch went all the way to 1002, which is dryer than I wanted.
So this is where things went sideways. I combined the two batches into one large carboy for secondary. Suddenly it starts bubbling again. Am I going to end up with 7 1/2 gallons of a very dry, thin dark ale? If so, can I add a little lactose and maltodextrin to bring the body and the sweetness back?

 

If the enzyme was used in the mash, and then you boiled the wort, the enzyme would be deactivated by the boil. That 1.002 is the reason you don't want to use it in the future.

 

Your beer contains a large amount of CO2, more than it can possibly hold more than temporarily. When you move the beer that movement causes the beer to expel some of the excess CO2. That's probably why your airlock started bubbling again.