RE: [Irradiation of foods]

[Marty Jamieson <martyj@swiftdesk.com>]

Keith and Chris:



One of my concerns is the possible formation of trans-fatty acids, which are considered to be a significant contributor to heart disease.  I personally do not look forward to the widespread use of food irradiation.



Marty Jamieson



-----Original Message Starts Here-----

From: Keith.Millington@csiro.au

Sent: Thu, 21 Nov 2002 15:55:17 +1100

To: chofmeyr@nnr.co.za, radsafe@list.vanderbilt.edu

Subject: Irradiation of foods



Hi Chris, 



One of my current interests is in free radical oxidation of proteins. If dry

proteins, for example the fibrous proteins wool and silk, (and also certain

amino acids)  are mildly irradiated with gamma or UV radiation you can

easily detect free radicals using ESR (electron spin resonance)

spectroscopy. It is interesting to note that "dry " wool is hydrophilic and

contains about 15% w/w adsorbed water, which varies depending on relative

humidity.



In the presence of oxygen these radicals very gradually decay (if left for

more than 24 hours or so) and form oxidised products. In a nitrogen

atmosphere the radicals persist indefinitely (if the irradiated samples are

kept in the dark). They will later decay if exposed to atmospheric oxygen.

My naive knowledge of food oxidation processes suggests that oxidation is

usually associated with spoilage, particularly for fresh foods. Clearly

thermal oxidation occurs during cooking, although in my experience there are

usually  different mechanisms and products involved in thermal, photo and

radiolytic oxidation processes.



One of the other factors involved in treating proteins with

gamma-irradiation is they quite often undergo serious colour changes. 



My question is, has much research been reported on various different

foodstuffs  to look at the nature of the oxidation products  and colour

changes that occur by using gamma irradiation ? It seems to me that may be

some interesting R&D to do in this field. To my knowledge, the only

foodstuffs imported into Australia for human consumption that are gamma

irradiated are certain spices and herbs, and I am aware of some reported

work on these. 



Best regards, Keith 





************************************************************************

You are currently subscribed to the Radsafe mailing list. To unsubscribe,

send an e-mail to Majordomo@list.vanderbilt.edu  Put the text "unsubscribe

radsafe" (no quote marks) in the body of the e-mail, with no subject line.

You can view the Radsafe archives at http://www.vanderbilt.edu/radsafe/





-----Original Message Ends Here-----

 

-

Marty Jamieson

martyj@swiftdesk.com

____________________________________________________________________________

Swift Desk

http://www.swiftdesk.com/

Free E-mail, web site hosting, file storage, online bookmarks, & day planner