Food irradiation

[Brian_Stymest@uml.edu (Brian Stymest)]

-----Original Message-----
From:	radsafe@romulus.ehs.uiuc.edu [SMTP:radsafe@romulus.ehs.uiuc.edu]
Sent:	Tuesday, February 17, 1998 4:51 AM
To:	radsafe@romulus.ehs.uiuc.edu
Subject:	Re: food irradiation stuff (radiation biology lesson?)


Subject: food irradiation stuff (radiation biology lesson?)
Author:  Chasmig@aol.com at hubsmtp
Date:    2/16/98 10:09 PM


     
The question expressed concern about "living" food, fruits and veggies. 

[*]  	During the food irradiation process, fruits, vegetables, and seeds have already been "picked" from their stems, with the 	exception of the seeds, of course. The fruits and vegetables at this point have become static. Their cells are no longer 	dividing, they are no longer growing.

How is it that radiation alters bacteria and parasites to the point of  death but 
does not significantly affect the living veggies?  A complete carrot plant can 
be grown from a single cell.
     
[*]  	Bacteria are present and still living on the now static "picked" fruit, or veggie. However, the bacteria or more specifically, 	their cells are still dividing and multiplying. The irradiation of the fruit or vegetable affects the bacteria by damaging their 	ability to reproduce, their ability to divide. Since they cannot divide properly they, the bacteria, die off.

     
How can you say that radiation kills bacteria but does not affect the food "in 
so many words", without it sounding like an article of faith? Why doesnt the 
DNA damage to the bacteria also damage the DNA of the food? I guess the hard 
part is explaining why damaged veggie DNA doesnt matter. I suppose it would 
account for the slight loss of vitamins.

[*]  	As in any pastuerization process or in a process where a food product is exposed to heat or ultraviolet, chemical bonds are 	broken. Free radicals are produced in pastuerization as well as from irradiation. These free radicals go on to later 	recombine or break down some molecular chains, but nothing toxic comes about from this.
   
  [*]  I hope this helps,

	Brian Stymest
	UMass Lowell
	Radiation Safety Office

	Standard Disclaimer as usual, this my opinion.