Arkan Trading wrote on 27 February:
"I have recently heard about carbon monoxide gas treated tuna in the form
of vacuum packed tuna loins. Can anyone comment on the effect of carbon
monoxide gas on humans? Is it acceptable according HACCP norms ?"
It would have been useful if anonymous correspondent from Arkan Trading had
been a bit more specific about how they came about this information, and
made clearer if they really meant vacuum packed tuna, MAP tuna, or frozen,
packaged or not, tuna as the heading has it.
I believe tuna and salmon have been packaged as MAP products with the
addition of carbon monoxide in the gas mix, but I do not know if this has
been on a commercial basis. The question of the use of CO with fish
products was put to me a few months ago and I looked at the literature,
particularly reviews, on MAP and did not come across any mention of use of
CO in fish products other than aside in a report by the UK MAFF Advisory
Committee on the Microbiological Safety of Food, 'Report on Vacuum
Packaging and Associated Processes' to the use CO for maintaining the red
stripe of salmon, but no references are cited. Of course that does not mean
it has not been used, even if only on a trial basis. It has been at least
investigated for red meat products. It gives the meat a pink colour which
is thought to be desirable. There is a review of this by Sorheim, O., Aune,
T, & Nesbakken,T. Technological, hygienic and toxicological aspects of
carbon monoxide used in modified-atmosphere packaging of meat, Trends in
Food Science & Technology, 1997, 8, 307-312. The review refers to meat
being packaged in gas mixtures containing 60-70% carbon dioxide, 30-40%
nitrogen, and less than 0.5% CO. The authors concluded there was no health
risk to consumers of meat packaged in this mixture.
Whether or not CO in packaged meats or fish presents a risk to health, food
regulations in some countries will forbid, or at least, not permit, its
use. The EU Directive on food additives (Council Directive No 95/2/EC of
20 February 1995 on 'food additives other than colours and
sweeteners'),does not list CO as a permitted additive so the use of CO in
packaged fish would not be permitted in the EU. I believe its use for
meat/fish products is not permitted in the USA, (though its use for
vegetable products is), but perhaps someone from FDA would state what the
position is.
Peter Howgate