From: jil@donuts0.uucp (Jamie Lubin)
Subject: Re: Cooking/Heating Protein--Last Beating of A Dead Horse??
Reply-To: jil@donuts0.uucp (Jamie Lubin)
Organization: Bellcore, Piscataway, NJ
Distribution: na
Date: Mon, 28 Sep 92 13:36:47 GMT

Found a few things over the weekend that I'd like to share.  First, let me
state that I haven't been proposing eating raw chicken (I never do).

Let me begin with what I couldn't find.  Re Dr. Bruce Miller's statement,
"many milk proteins can be denatured by the usual pasteurization methods,"
the listed source was Tobes, John, Milk--Friend Or Fiend?, p. 68.
St. Catherine's, Ontario: Modern Publications, 1967.  I had no luck with this
at my county library (I assume because it's a Canadian publication?).

However, I did get the following from Diet And Disease by E. Cheraskin, M.D.,
D.M.D., W.M. Ringsdorf, Jr., D.M.D., J.W. Clark, D.D.S.:

(p. 22) Although not usually recognized, considerable protein destruction takes
place as foods are heated.

Butterworth, M.H. & Fox, H.C. The effects of heat treatment on the nutritive
value of coconut meal, & the prediction of nutritive value by chemical methods.
Brit. J. Nutrit. 17: #4, 445-452, 1963.

Clarke, J.A.K. & Kennedy, B.M. Availability in wholewheat bread & in selected
breakfast cereals.  J. Food Sc. 27: #6, 609-616, November-December 1962.

Gates, J.C. & Kennedy, B.M. Protein quality of bread & bread ingredients.  
J. Am. Dietet. Assn. 44: #5, 374-377, May 1964.

This has been underscored by an editorial in Nutrition Reviews.  It has been
postulated the dry heat processing of proteins produces a new lysine linkage
which is either not digestable by enzymes or is so slowly digested that lysine
enters the bloodstream too late to participate with the rest of the assimilated
amino acids in tissue formation.  More severe heat damage to proteins results
when moist heat is used.  When reducing sugars (e.g. glucose) are present true
destruction of amino acids has been repeatedly corrorborated.  This destruction
may account for a loss of 50% of the lysine, arginine, tryptophane & histidine
content.

Present status of heat-processing damage to protein foods.  Nutrit. Rev. 8:
#7, 193-196, July 1950.

A startling example of protein destruction during the cooking of food was
reported at the Mead Johnson Research Center in Evansville, Indiana.  It was
discovered that the stockpile of survival biscuits & crackers developed by the
Office Of Civil Defense for use in catastrophic emergencies was significantly
deficient in essential amino acid content.  Actually 2/3 of the lysine was
destroyed presumably during the baking of these foods (Table 1.14).  As one may
note in Table 1.14 (sorry, I'm not going to type a 5-column table), there was
a great discrepancy between the lysine content of the survival rations as
calculated from food tables & the actual amount based on chemical analysis.

Longenecker, J.B. & Sarett, H.P.  Nutritional quality of survival biscuits &
crackers.  Am. J. Clin. Nutrit. 11: #5, 291-296, November 1963.

(p. 278-9)  A recent literature review cites evidence which may possibly
indict the heating of animal protein as a factor in the etiology of
atherosclerosis & subsequently, coronary thrombosis.  Experimental studies
are noted to show that both heated animal protein & cyanocobalamin, freed
during the heating process, enhance membrane permeability.  The reviewer
concluded that any factor enhancing this physical characteristic (membrane
permeability) would tend to increase the deposition of lipids.

Annand, J.C.  The case against heated animal protein.  J. Atheroscler. Res. 3:
#2, 153-156, March-April 1963.

Comments please.
Newsgroups: sci.med.nutrition