Brewing enzyme = amylase?

[tonybrown]

Planning a Durden Park recipe (26degree Porter Extra (1810) Brakspear's).

The recipe calls for a 1:1:1 ratio of Pale, Amber and Brown Malt grist. It further notes that a brewing enzyme will be needed for complete mashing.

My question: is amylase (as available from Hop & Grape) the brewing enzyme that the recipe will require? And what would the proportion of alpha and beta amylase be (if this matters)?

My understanding is that brewing enzyme is required becuase modern Amber and Brown Malt has no diastatic enzyme so will not contribute to converting starch into sugar; ordinarily these malts would not be used in a >10% of total grist bill quantity for this reason. However, I am going for a historical recipe recreation.

The general advice from Durden Park in their book 'Old British Beers and How to Make Them' is to mash stiff (1:1 grist to liquor by volume?) at 66 degrees centigrade for 3 hours.

Share your wisdom please!

[Aleman]

I'd use the diastatic amber

but it will still not convert fully, the enzyme you are looking for is amyloglucosidase which is better known as dry beer enzyme . . . Unlike with a 'stuck beer' you are not adding it to the fermenter this time but to the mash tun ( another article for Brewers contact 'additional enzymes and how/when to use' ). I would use a couple of sachets and add it to the grist, before mashing, and mash it cool at around 62-64C

[Graham]

It looks as if that might be the stuff you want, but it isn't clear (Why are home brewing web sites so ruddy awful and non-descriptive). There a several forms of commercially available amylase, and that is listed as a wine additive, after all. Without knowing what is in it, it is not worth gambling with it.

Amyloglucosidase is not what you want because it attacks non-fermentable dextrin and breaks it down into simpler sugars that are fermentable. If you used this you would have a dry, bodiless beer.

However, the enzymes do not get used up, as such, but when they have nibbled at one link they move on and nibble at another. Even though your grist will have only a third of the normal enzymic activity, it will eventually convert all of your starch; it just takes longer. You say that the recipe does advocate a three-hour mash; which might be long enough. I would resign yourself to a long mash period and mash until starch end-point is reached, or even mash overnight.

That book, or at least the early editions, gets away with murder in my view. Old-time brown malt, although diastatic, was nowhere near as brown as modern brown malt; a fraction of the colour. I would be wary about the the 1:1 grist-to-liquor ratio too. That might be a tough one to implement and you run the risk of achieving a poor mash efficiency. The grain will absorb most of the liquor if not all of it. You do not want any dry pockets remaining.

[tonybrown]

Thanks for the advice guys.

The 1:1 grist to water ratio is my interpretation of 'mash stiff'; would 1:1.5 be safer given Graham's contribution?

In fairness to Durden Park they do detail how to roast Pale Malt to re-create Brown Malt, though I can't be bothered. Of course the smokey character would be missing unless the heat source was a wood fire. What type of wood to burn though?

If I mash overnight should I start at the highest temperature (68 degrees centigrade) and hope that my basic mash tun (converted cool-box, 21L capacity), with the addition of my down filled winter coat, will stay warm enough through the night?

Thanks again.

[Aleman]

The benefit of adding the enzymes to the mash is that you will be terminating the enzyme activity in the boil, so you will not end up with a thin dry beer.

One of the problems with going for a long mash time is that mash enzymes are thermally labile . . . temperature destroys them . . .this does not happen instantly, but its more of a half like reaction only the half life decreases with increasing temperature. Another important thing is that beta amylase has a shorter 'half-life' than alpha amylase, so even though eventually all of the mash converts you may very well end up with a thick sweet mash (IIRC David Edge has reported this happening several times when he used high qtys of Amber/brown malt).

A thick mash would be around 2L/Kg, and a thin one around 3L/Kg personally I wouldn't worry about it as it only really has an effect with bigger beers . . . and they turn out sweeter and less fermentable than normal ones.

[Graham]

The benefit of adding the enzymes to the mash is that you will be terminating the enzyme activity in the boil, so you will not end up with a thin dry beer.

It'll be too late by then by a long way; the damage will already have been done. An enzyme is not going sit around and wait patiently to discover whether or not it is going to be boiled.

[johnmac]

Why are home brewing web sites so ruddy awful and non-descriptive

Maybe because the manufacturers are to lazy to provide the information, the shops are too lazy to ask for it and so are we, the punters? Who do you blame first