Charles
CO content of fish flesh can be determined by GLC, but unfortunately the
papers I am aware of with the procedure are, with 1 exception, in Chinese or
Japanese. The bibliography is appended to this message.
The paper, Ishiwata, H., Takeda, Y., Kawasaki, Y., Yoshida, R., Sugita, T.,
Sakamoto, S., Yamada, T., 1996, Concentration of carbon monoxide in
commercial fish flesh and fish flesh exposed to carbon monoxide gas for
color fixing, Journal of the Food Hygienic Society of Japan, 37, 83-90, is
in English and the procedure for CO measurement as given in the Methods
section is:
"Determination of CO in fish flesh by gas chromatography
CO was determined according to the Notice from the Ministry of Health and
Walfare8) as described below. Fish flesh was homogenized for 1 min with
twice its weight of water under ice cooling. The homogenate was centrifuged
for 10 min at 3,000 rpm at 10?C. The supernatant, 50 ml, was poured into a
100 ml head-space bottle, then 5 drops of n-octyl alcohol, 5 ml of water,
and 20 ml of 20% sulfuric acid were added. A cap with a septum and an O-ring
was placed on the bottle, which was closed as quickly as possible. The
mixture was shaken vigorously for 2 min and left for 10 min. The mixture was
again shaken for 1 min just before sampling of the head-space gas. One
milliliter of the headspace gas was taken and injected into the gas
chromatograph. CO was separated from other gases on the column and was
reduced to methane in the methanizer for detection by FID. The retention
time and peak area were compared with those obtained with the calibration CO
gas."
Additionally the abstract of Takeda, Y., Kawasaki, Y., Sugita, T., Sakamoto,
S., Sato, K., Yoshida, R 1995, Inspection of carbon monoxide in imported
tilapia, Bulletin of the National Institute of Health Sciences, 133, 74-76,
(in Japanese), states:
"Carbon monoxide in imported tilapia was determined with a gas chromatograph
equipped with a molecular sieve 13x column (2.3 m), a methanizer and a FID
for the inspection of imported food."
Carbon monoxide treatment of fishery products is not permitted in the EU and
imported fish should be tested if its use is suspected, but I do not know
the recommended procedure.
Peter Howgate
Bibliography
Chow, C.-J., Hsieh, P.-P., Tsai, M.-L., Chu, Y.-J. , 1998, Quality changes
during iced and frozen storage of tuna flesh treated with carbon monoxide
gas, Journal of Food and Drug Analysis, 6, 615-623.(In Chinese)
Hsieh, P.-P., Chow, C.-J., Chu, Y.-J., Chen, W.-L., 1998, Change in color
and quality of tuna during treatment with carbon monoxide gas, Journal of
Food and Drug Analysis, 6, 605-613. (In Chinese)
Miyazaki, H. Abe, M., Asanoma, M, Nagai, Y. Nakajima, M., Miyabe, M., 1997,
Simple determination of carbon monoxide in fish meat by GC, Journal of the
Food Hygienic Society of Japan, 38, 233-239. (In Japanese).
----- Original Message -----
From: "Santerre, Charles R" <santerre@purdue.edu>
To: <seafood@ucdavis.edu>
Sent: Monday, May 14, 2007 7:56 PM
Subject: Testing for carbon monoxide treatement
Dear members: Is anyone aware of a way to test for carbon monoxide
treatment of tuna loins? The outside of the loin was a beautiful crimson
red and the inside was brown. I have received a request but do not have
the answer. Thank you in advance for providing some information. Charlie
Charles R. Santerre, Ph.D.
Professor of Food Toxicology
Foods and Nutrition
Purdue University
Stone Hall, Rm. 205
700 W. State St.
W. Lafayette, IN 47907-2059
ph 765/496-3443
fax 765/494-0674
email: santerre@purdue.edu <mailto:santerre@purdue.edu>
http://fn.cfs.purdue.edu/santerre/
________________________________
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