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From:	John Mayer (c-71-236-40-29.hsd1.tn.comcast.net)
Subject:	Re: SOYMILK CRISIS
Date:	July 18, 2007 at 9:32 pm PST

In Reply to: Re: SOYMILK CRISIS posted by Marie Oser on April 15, 2007 at 8:21 pm:

RE: the question regarding the use of raw soy beans to make soy
milk; it is my understanding that soybeans should be cooked for
good nutrition. Otherwise the digestion of not only the proteins in
soybeans is inhibited but, also, that of any other proteins you
ingest at the same time. Quoting from THE NUTRITIVE QUALITY
AND THE TEYPSIN INHIBITOR CONTENT OF SOYBEAN FLOUR
HEATED AT VARIOUS TEMPERATURES by B. J. Westfall and S. M.
Hauge, 1947

The presence of a substance in soybeans that inhibited the
proteolytic action of pancreatin was demonstrated by Ham
and Sandstedt ( '44) and by Bowman ( '44). Adding a concen
trate of the inhibitor to an otherwise adequate diet decreased
the growth rate of chicks, as shown by Ham, Sandstedt and
Mussehl ('45). Klose, Hill and Fevold ('46) showed that a
similar concentrate would decrease the growth rate of rats,
although this concentrate was not specifically identified as an
inhibitor of a proteolytic enzyme. A crystalline protein with
strong trypsin-inhibiting activity was isolated from soybeans
by Kunitz ('45, '46), who later ('47) characterized its proper
ties, showing its strong affinity for trypsin and its much weaker
affinity for chymotrypsin. Bowman ( '46) presented evidence
that more than 1 trypsin inhibitor is present in soybeans.
It appeared probable that the trypsin inhibitor caused the
difference in nutritive value between raw and heated soybeans.
The results of the present investigation confirmed this as
sumption. Studies were also made of the period and the tem
perature of heating necessary for the experimental prepara
tion of soybean flour of optimal protein quality.

Has new research disproven this?

Yours truly,
John Mayer

• VSET