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Earlier today I posted a comment to this list about barley amylase possibly
being used in the production of sake. I also posted this question to the new
sci.bio.food-science newsgroup and have already received two replies. Note
comment about production of potato liquors in the first reply. I will repost
here any other answers received.
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From: [log in to unmask] (Mikael Larsson)
Newsgroups: sci.bio.food-science
Subject: Re: Is barley amylase used in liquor production?
Date: 6 Jun 1995 16:36:36 GMT

Don Wiss ([log in to unmask]) wrote:
: I once heard that barley amylase (a starch-splitting enzyme which
: hydrolyzes complex sugars to glucose) was used in the processing of sake.
: Is this true of all sakes? Is barley amylase used in the production of any
: other alcoholic beverages?

Hi,

>From what I have picked up in books and on other newsgroups
(rec.crafts.brewing), traditional Sake is not made by the use
of barley amylase. The starch in the rice is broken down to
fermentable sugars by something called koji, which I believe
is some kind of fungus or possibly an enzymatic substance
made out of certain fungi (hopefully someone else could fill in here).

Whether the enzyme in koji is identical to the enzyme in barley
malt, I don't know. I don't know if the products of the "starch-splitters"
are the same either. As for malt, alpha amylase produces maltose,
whereas beta amylase produces dextrine, a more complex and non-fermentable
sugar.

As for your second question, barley malt is one of the ingredients
in whisky. I also believe that is is used to split the potatoe starch
in potatoe based liquors (It certainly was in the olden days at least,
but perhaps there are other enzymatic substances used today - could
anyone fill in?).

Only my 2 oere,
Mikael Larsson

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From: [log in to unmask] (Jeremy Ballard Bergsman)
Newsgroups: sci.bio.food-science
Subject: Re: Is barley amylase used in liquor production?
Date: 6 Jun 1995 11:24:42 -0700

As a homebrewer (beer) I can speak to a few of these questions:

Mikael Larsson <[log in to unmask]> wrote:

>...The starch in the rice is broken down to
>fermentable sugars by something called koji, which I believe
>is some kind of fungus or possibly an enzymatic substance
>made out of certain fungi (hopefully someone else could fill in here).

Koji is a fungus.  I believe the genus is aspergillus.

>Whether the enzyme in koji is identical to the enzyme in barley

The enzyme is not the same.  I say this because it has a different
optimal temperature.  I don't know what kind of sugars the Koji
enzyme(s) produce(s).

>malt, I don't know. I don't know if the products of the "starch-splitters"
>are the same either. As for malt, alpha amylase produces maltose,
>whereas beta amylase produces dextrine, a more complex and non-fermentable
>sugar.

I believe you have alpha and beta reversed here.  Also it is not so
much that alpha amylase produces dextrines than that it cleaves
alpha 1-6 glycosidic linkages in the middle of starch chains, as
opposed to beta amylase which cleaves them specifically two from the
end of the chain (maltose is 2 glucoses).

Commercial brewers of beer use various starch- and dextrine-degrading
enzymes.  This is mainly in the production of "lite" and dry beers.
I don't know what the biological source of these enzymes is.

Jeremy Bergsman
[log in to unmask]
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Don <[log in to unmask]> New York City