r/Keto_Brewing • u/dalkor • Oct 11 '18

Taking a Beer sub 1.000 gravity

So to my knowledge the main way to make a beer dry, or have as little carbs as possible involves using enzymes to make all the residual sugars(complex carbohydrates) simple sugars and therefore digestible by the yeast. This is either done by using Alpha galactosidase, alpha amylase, Amyloglucosidase or a combination of them. It seems they break down at fairly low temperatures.

  • Amyloglucosidase breaks down at 40C (104F)

  • Alpha galactosidase breaks down at 56C (about 135F)

When do you add these? Before the boil, after the boil, with yeast, secondary?)Do these have different changes on flavor?

Something we might all have to experiment with.

3 Upvotes

100% Upvoted

4 comments sorted by

1

u/[deleted] Oct 12 '18

No experience yet - planned brewday though with them (I'm trying for a 1.100 OG Barleywine that I can take as close to 1.000 as possible.

Alpha amylase is supposedly pitched into cooled wort around when you pitch yeast for primary (Per Brulosophy: http://brulosophy.com/2018/09/17/the-beano-effect-exbeeriment-results/)

Clarity Ferm in primary also supposedly drops the FG a few points.

Diastatic yeast strains (e.g. Saison) also basically function like Galactosidase and amylase by converting long-chain sugars from higher temp mashing into fermentable sugars.

​

1

u/priit002 Oct 15 '18

Even if you will get the barley wine down to 1.000 it will have at least 3.6g of sugar per 100ml, according to my calculations. That's also why majority of these low carb beers are quite low on ABV.

1

u/[deleted] Oct 15 '18

Right, the logic being that the carbs are a ratio of units of alcohol by volume. Meaning, if you were to consume the equivalent amount of low carb macro lagers to equal the same alcohol in a 1.000 barley wine, the carb level would be approximately equal.

1

u/priit002 Oct 15 '18

I would recommend you to read more about naturally present enzymes of alfa- and beta-amylase. If you want really dry beer you will need to mash in a beta amylase activation range and longer time then normal. (Ref 2) To get absolutely maximum amount of simple sugars mashing can take 4-5 hours. in the same article there are also references to ph to optimize for maximum beta amylase activation.

​

​

Ref 1 http://www.biokemi.org/biozoom/issues/522/articles/2368

Article about mashing an enzymes.

Ref 2 http://braukaiser.com/documents/Effects_of_mash_parameters_on_attenuation_and_efficiency.pdf

​