Mashing enzymes such as Amylase powder convert the starch in beer malt into soluble sugars
With this knowledge, the home brewer can manipulate enzyme activity to can control the fermentability of their wort.
Amylase enzymes are proteins. Their specific role is to 'catalyze biochemical reactions', which means that they enable a reaction to occur quickly and crucially at the temperature of living organisms (talking yeast here).
Amylase enzymes are proteins. Their specific role is to 'catalyze biochemical reactions', which means that they enable a reaction to occur quickly and crucially at the temperature of living organisms (talking yeast here).
There is amylase in human saliva - digestion starts in the mouth after all!
A starch molecule, as a basic description, is a group of glucose molecules linked together. Enzymes will break those links allowing yeast to better ferment.
Alpha-amylase contributes to the digestion of starch by breaking internal bonds between the glucose molecules. As the starch molecules are opened up, they break into a range of intermediate sizes.
In comes beta-amylase which further digests these newly sized molecules mostly into maltose—a sugar of two glucose units—but also to glucose itself and to the three-glucose molecule maltotriose. You can add glucoamylase instead of beta as it does the same job on starch.
This will occur effectively when the wort is properly pH balanced and the ideal temperature has been realised.
The temperature of your mash is key to how effective amylase.
In terms of timings, some brewers will add amylase immediately after adding strike water or about 30 minutes or so into an extended all-grain mash taking longer than 60 minutes.
So, brewers use amylase to ensure an efficient breakdown of the malt into maltose and sugars - meaning there is more food for the yeast to eat, meaning you get more alcohol - this is called attenuation.
I'm a hungry enzyme... |
The one-two punch of alpha and beta amylase in starch digestion
In a brewer’s mash, we are concerned with the activity of two main enzymes, alpha and beta amylase, and their effect on starch.Alpha-amylase contributes to the digestion of starch by breaking internal bonds between the glucose molecules. As the starch molecules are opened up, they break into a range of intermediate sizes.
In comes beta-amylase which further digests these newly sized molecules mostly into maltose—a sugar of two glucose units—but also to glucose itself and to the three-glucose molecule maltotriose. You can add glucoamylase instead of beta as it does the same job on starch.
This will occur effectively when the wort is properly pH balanced and the ideal temperature has been realised.
These two compounds are also great for breaking down corn-type adjuncts when making spirits (just watch that methanol production eh?)
When to add amylase enzyme to the wort
The temperature of your mash is key to how effective amylase.
If you increase the temperature immediately after adding amylase you're working against yourself.
Amylase works best at 150-155°F. Much higher than that and the enzyme is destroyed by the heat.
Amylase works best at 150-155°F. Much higher than that and the enzyme is destroyed by the heat.
A common practice is to hold it at its activation temperature for an hour to allow full conversion of starch, then cool it rapidly to your fermentation temperature once the gelatinization of the malt/starch is complete.
This wiki advises:
This wiki advises:
The ideal situation you want is to attain is one in which your mash rests at a temperature between 66° and 70° C (150°-158° F) to allow the amylase enzymes to do their work. The colder the rest, the more fermentable sugars will be available for fermenting, and therefore the higher alcohol content in the final beer. The hotter the temperature, the more unfermentable sugars will reach fermentation, and thus the fuller the mouth-feel. This is, of course a comparison of otherwise duplicate mashes. Remember, the enzymes will work outside their optimum temperatures, so given an adequate amount of time, all starches can be converted to fermentables.
We suggest you read the whole wiki as it gives a very sound scientific description of mash temperatures and the various methods use you can use enzymes with. This page is a great read too.
The pH level of your beer (both mash and wort) affects the way your beer turns out in several ways. Enzyme function is affected by an out-of-whack pH level, the efficiency of your hops can be manipulated and it affects how well your yeast ferments your brew.
Brewers test for pH using meters - a sample is taken from the work and an electrode is used to take the reading - pH is then adjusted accordingly using chemicals like calcium chloride or lactic acid.
This video gives a really great introduction in to using alpha and beta-amylase and its relationship to beer mash:
Extra for experts: Does adding enzyme to the mash influence the taste of the beer?
Why ph of the mash is important for enzyme action
The pH level of your beer (both mash and wort) affects the way your beer turns out in several ways. Enzyme function is affected by an out-of-whack pH level, the efficiency of your hops can be manipulated and it affects how well your yeast ferments your brew.
Brewers test for pH using meters - a sample is taken from the work and an electrode is used to take the reading - pH is then adjusted accordingly using chemicals like calcium chloride or lactic acid.
This video gives a really great introduction in to using alpha and beta-amylase and its relationship to beer mash:
Extra for experts: Does adding enzyme to the mash influence the taste of the beer?
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