the following link shows a similar method to that one described by Peter
Howgate
http://www.accessdata.fda.gov/scripts/oc/scienceforum/sf2006/search/preview.cfm?abstract_id=1072&backto=category
Board Number: A-86
Title: Gas chromatography/mass spectrometry determination of carbon monoxide
in commercially treated tuna and mahi-mahi
W. H. Wu , C. R. Anderson , PRLNW/SPRC, ORA, FDA, Bothell, WA
Background: Discoloration of tuna product can be effectively
prevented when carbon monoxide (CO) is bound to the Fe(II) binding site of
myoglobin in tuna muscle. Commercial CO treatment of tuna and a few other
finfish species is therefore an increasingly popular practice to improve
product acceptance in the commercial market. In the US, tuna treated with
CO should display labeling indicative of that process.
Methods: CO contents in tuna and mahi-mahi were measured by a GC/MS
method developed in our laboratory. GC/MS analysis was completed by
injecting 100 mL from headspace of a mixture of CO-distillated water, after
bound CO was chemically released from fish tissue using sulfuric acid (5M).
Results: Using the method described in this study, indigenous CO
contents of fresh Ahi tuna and mahi-mahi samples were found to be close to
or less than 150 ng/g and 100 ng/g, respectively. Commercially CO-treated,
vacuum-packaged tuna from multiple sources consistently showed CO level near
or greater than 1 mg/g, while CO level in the only CO-treated frozen
mahi-mahi sample was in the 500 ng/g range. Treated specimens appear
distinguishable from untreated samples as the difference in CO content
between these two categories was in the range of one order of magnitude.
Conclusions: Our findings suggest an easy quantitative and
confirmative method for CO in fish using widely available instrumentation.
This method may be useful for regulatory purpose, with proper validation, in
determining whether a commercially available fishery product has been
exposed to CO even if not labeled as such.
Jerry Oliveras, Laboratory Director
AEMTEK, Inc. - www.aemtek.com
46309 Warm Springs Blvd., Fremont, CA 94539
phone 510-979-1979 fax 510-668-1980 Cell: 510-520-0755
email: jerryo@aemtek.com
----- Original Message -----
From: "Seafood research and extension information exchange"
<seafood@ucdavis.edu>
To: "Seafood research and extension information exchange"
<seafood@ucdavis.edu>
Sent: Tuesday, May 15, 2007 10:01 AM
Subject: SEAFOOD digest 2593
>
> SEAFOOD Digest 2593
>
> Topics covered in this issue include:
>
> 1) Testing for carbon monoxide treatement
> by "Santerre, Charles R" <santerre@purdue.edu>
> 2) Re: Testing for carbon monoxide treatement
> by "P Howgate" <phowgate@clara.co.uk>
> 3) re: temperature control chart
> by DENNIS TIOTANGCO <dtiotangco@yahoo.com.ph>
> 4) Re: temperature control chart
> by CANSALMON@aol.com
> 5) New EU Health Certificate
> by "Evert Liewes" <evertliewes@hotmail.com>
> 6) RE: New EU Health Certificate
> by Ivan Bartolo <I_Bartolo@Seafish.co.uk>
> 7) RE: New EU Health Certificate
> by "Sanchez, Sergio" <Sergio.Sanchez@inspectorate.com>
> 8) Re: New EU Health Certificate
> by shetty TS <ts_shetty@yahoo.com>
>
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