From: malodah@pbhyf.PacBell.COM (Martin A. Lodahl)
Subject: Re: Quality of malt extract (_long!_)
Reply-To: malodah@PacBell.COM (Martin A. Lodahl)
Organization: Pacific * Bell, San Ramon, CA
Date: Sun, 22 Nov 1992 20:43:50 GMT

In article <92112216458@ritz.mordor.com> ritz@ritz.mordor.com (Christopher Mauritz) writes:
>I remember sometime ago a university (in Canada?) did a study on
>malt extracts from many different sources to check for the addition
>of refined sugar.  Apparently, so many of the brands were
>"contaminated" with added sugar that the school refused to publish
>the brand names.
>
>Could anyone here "in the know" provide more details?  I don't have
>the facilities yet to do my own mashing and I'd like to avoid those
>brands which add sugar to the "broth".

I posted something on this to HBD back in '90 or '91.  Here's an
article I wrote on the subject that originally appeared in the newsletter
of the Gold Country Brewers' Association in September '91:

		STUCK ON EXTRACTS, by Martin Lodahl

Have you ever brewed with extracts?  Ever had a "stuck" fermentation?  
Then this article's for you, though you probably won't like it.  
Because the fact is, malt extracts aren't always what they say they 
are, and the homebrewing community is just beginning to wake up to 
that fact.

The flap all began in Zymurgy, Vol. 13 #5, Winter 1990.  On 
page 15, in Dan Fink's "Brew News" column, was an item describing 
a report entitled "Malt Extract:  Relationship of Chemical 
Composition to Fermentability", by J. Paik, N. H. Low, and 
W. M. Ingledew of the Department of Applied Microbiology and 
Food Science, University of Saskatchewan, Saskatoon, Canada 
S7N 0W0.  It was presented May 15 1990 to the American Society 
of Brewing Chemists, and published in the February 1991 issue 
of their Journal.  In his column, Fink reported on their 
research, a combination of High Performance Liquid Chromatography 
and fermentation studies, which disclosed the disturbing presence 
of substantial amounts of glucose syrup, invert syrup/liquid sucrose, 
and high fructose corn syrup in the extracts tested, without always 
naming those ingredients on the label.  They also discovered poor 
fermentation from some extracts, due to a deficiency in the free 
amino nitrogen (FAN) content normally provided by barley malt (had 
any stuck fermentations lately?).  In the presentation, they did 
not identify the extracts tested.

I don't have to tell you what a storm that raised!  The AHA 
followed up on it, and again in Dan Fink's column (page 14) 
in the Summer 1991 issue of Zymurgy (Vol. 14 #2) they published 
a letter from Professor Ingledew in which he said that they 
indeed were not planning to release the names of the extracts 
tested.  They felt they couldn't be sure whether the adulteration 
was done by the manufacturers, or by the distributors.  They also 
felt their sample might not be representative, as they had only 
tested 44 "lager" extracts, and no "ale" extracts (their 
terms).  They didn't feel they had the time or money to handle 
either additional testing or possible legal action.  They also 
felt that the burden of following up on the problem they'd identified 
rested with the brewing industry, through the marketplace.  Then 
Professor Ingledew closed with this paragraph: 


	In spite of my comments above, I have complete 
	confidence in the results obtained in my lab 
	by my colleagues.  There is no doubt that 
	some manufacturers are profiting from the 
	addition of lower cost corn sugars to malt extract.

Well!  Where does that leave us?  Neither of the Zymurgy articles 
made it clear what percentage of the extracts tested had been 
"juiced", or to what degree.  And, of course, we have no idea 
what they were testing.

Recently, Russ Wigglesworth of the San Andreas Malts provided me 
with a copy of the original report.  It makes fascinating reading, 
and clears up some points raised by the Zymurgy articles.  
Significantly, one of the search keywords is "Stuck 
fermentation".   The early part of the report describes 
the methods used with a level of detail one would expect 
of a paper of this nature.  What would interest us is that 
"Forty-one malt extracts (all of light lager type) were 
purchased from a local brewing supply store.  These malt 
extracts were called beer kits, home brew kits, concentrated 
brewing worts, or malt extracts for home brewing ... In 
addition, one bulk malt extract sample from a malting company 
and two bulk malt extract samples from a local brewpub were 
obtained".  Red Star Lager yeast was used for all the fermentation 
studies.

The first sign of real trouble apparently came when they noticed 
that the time required by the extract brews to drop from 12P to 
6P varied from a low of 45 hours to a high of 173, compared to 
the baseline of 51 hours for the Molsen wort.  In fact, "93% of 
the malt extracts had demonstrably slower fermentation rates 
than the standard wort", and "correlation between initial FAN 
level and fermentation time (to 6P) yielded an r value of 
0.75 -- a correlation significant at the 0.01 probability level" 
for all you statisticians out there.  For the rest of us, that 
means that the slow-fermenting worts were also the ones with low FAN 
content.  They experimented with various supplements in various 
concentrations to improve this, settling on yeast extract with 
added minerals (similar to the commercially available yeast 
nutrients, such as "Super Ferment" and others), though noting 
that performance was essentially the same at all tested 
concentrations, suggesting that saturation is soon reached.  In 
short, yeast nutrients appear to be much more helpful than we've 
previously been led to believe in conducting fermentation with 
extract worts.  That fact is rather surprising:  I, for one, 
wouldn't have expected there to be that much difference between 
the performance of an all-malt extract wort and an all-malt, 
all-grain wort.

The sugar profiles provided the real bombshell.  The researchers 
divided the extracts into 3 groups, according to the contents 
listed on the labels.  Groups 2 and 3 both had various supplements 
and adjuncts listed, and the analyses tracked pretty well with 
the labeling.  Group 1 extracts, however, "were labeled at 
the source as pure malt extracts".  Of the 21 extracts in that 
group, a commendable 14 had carbohydrate profiles "similar to 
the standard all-malt wort", which placed them in class 1.  From 
here I quote:  "Group 1 class 2 extracts had a D-glucose 
concentration 2.7 times that of the standard, with concomitantly less 
maltose and maltotriose.  The two possible explanations for this 
sugar profile are that wort production was carried out using a 
longer saccharification period during the mashing process 
(considered unlikely as the final ethanol concentration of the 
beer would then be >5%), or that a glucose syrup was added to the 
malt extract.  A single Group 1 class 3 extract was found to have 
88% of its total sugar content as D-glucose.  Because this sample 
did not contain any D-fructose, sucrose, maltose, or maltotriose, this 
product was highly adulterated with a high-glucose syrup".  WOW!  
A malt extract, without a trace of malt extract!  I am impressed!  
They continue:  "Carbohydrate analyses of all Group 1 extracts indicated 
that seven of the 21 samples labeled as pure malt extracts were 
adulterated with glucose syrup."

So there you have it.  We all know that it's quite possible to 
make very good beer using malt extracts, but most of us have at 
some time had some problem extract batches.  The degree of 
variation this study identifies suggests we may not always have 
been at fault.  The study suggests to me a few considerations:

*	If you're not at least partial mashing, add yeast 
	nutrient.  It can't hurt, and might help.

*	Don't add sugar to an extract wort.  It may already 
	have all it can stand.

*	All extracts are not alike.  If you're using a good 
	one, stick with it.


-- 
= Martin A. Lodahl    [DoD, AHA, NRA]  Systems Analyst, Pacific*Bell =
= malodah@PacBell.COM		Sacramento, CA, USA     916.972.4821 =
= If it's good for ancient Druids, runnin' nekkid through the wuids, =
= Drinkin' strange fermented fluids, it's good enough for me!!  8-)} =
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