Jan (jan.verhoeven@foodfocus.nl)
Tue, 25 Jan 2000 08:43:22 +0100
My point was that the fish might have ingested carotene containing
natural algae.
Jan
On 24 Jan 00, at 20:07, Andrew Strak wrote:
> The issue is that nobody would buy yellow haddock fillets. And even
> the regulatory bodies would object to the colour. Therefore that kind
> of discolouration is considered at present a defect and loss to the
> processor.
>
> Andrew Strak
>
>
> ----- Original Message -----
> From: J. (Jan) A.M. Verhoeven <jan.verhoeven@foodfocus.nl>
> To: <phowgate@rsc.co.uk>; 'Seafood List' <seafood@ucdavis.edu>;
> <abstrak@accesswave.ca>
> Sent: Monday, January 24, 2000 6:56 PM
> Subject: Re: Haddock Flesh Discolouration
>
>
> >
> > Hello,
> >
> > I am in the process of compiling a publication about permitted food
> > color additives and came across the following. Maybe it is of help:
> >
> > In the EU, like in USA, carotenes are permitted as food colors:
> > E-no. 160a(i): mixtures of carotenes. One of the permitted mixtures
> > is derived from algae, i.c. Dunaliella salina. These mixtures
> > contain (according to the "annex" of the legislation covering the
> > purity of the permitted colors): alpha- and beta-carotene, lutein,
> > zeaxanthin and beta-criptoxanthin.
> >
> > Zeaxanthin occurs in the publication mentioned by Andrew Strak.
> >
> > Best regards,
> >
> > Jan
> > visit my restyled site (also in English):
> > http://www.foodfocus.nl
> >
> >
> > On 23 Jan 00, at 20:54, Andrew Strak wrote:
> >
> > > Peter,
> > >
> > > Thank you for your insight. The fish was from the Barents Sea
> > > (unknown exact location, though). In the meantime I have come
> > > across one old paper by E.G. Bligh and W.J. Dyer 'Orange-red Flesh
> > > in Cod and Haddock" - J.Fish.Res.Bd. Canada, 16(4), 1959 not
> > > probably listed in any database anymore. Astaxanthin and
> > > zeaxanthin in the proportion of 2:1 were found to be responsible
> > > for the pigmentation of the flesh of Cod. Zeaxanthin was the only
> > > pigment detected in the flesh of a similarly pigmented haddock.
> > > Therefore concerning the carotenoid identification you are
> > > probably right on the point. What strange is that the colour
> > > intensity seems to be increasing with the time in frozen storage.
> > > And the incidence of the number of fish affected by the phenomenum
> > > in this case is also pretty high (5%), unlike your experience or
> > > reported by Blight and Dyer. Apparently there must some cargo ship
> > > carrying corn went down recently :-).
> > >
> > > Andrew Strak
> > >
> > >
> > > ----- Original Message -----
> > > From: howgate <phowgate@rsc.co.uk>
> > > To: <abstrak@accesswave.ca>; 'Seafood List' <seafood@ucdavis.edu>
> > > Sent: Sunday, January 23, 2000 5:36 PM Subject: Re: Haddock Flesh
> > > Discolouration
> > >
> > >
> > > > Andrew
> > > >
> > > > On 21 January you showed two pictures of haddock, one
> > > > discoloured. I
> > > assume
> > > > you were referring to the bright yellow fillet.
> > > >
> > > > Carotenoids can be taken up from the diet of animals and can
> > > > colour the flesh. A common example, in the USA at least, is the
> > > > yellow colour of corn-fed chickens. I assume this is due to the
> > > > carotenoid, zeaxanthin,
> > > that
> > > > imparts the yellow colour to corn. Nearer to home, the pink
> > > > colour of salmon, in the wild, is due predominately to the
> > > > carotenoid astaxanthin, and other carotenoids in minor amounts,
> > > > from crustacea in the diet. I can only write from experience of
> > > > haddock landed in Britain. I have come across light pink
> > > > colouration in haddock, and in cod, which is assumed to come
> > > > from crustacea in the diet, but I have not come across the
> > > > yellow colour shown in your picture. A number of carotenoids
> > > > other than the pink astaxanthin and canthaxanthin are found in
> > > > marine animals. Polychaete
> > > worms
> > > > are sources of a variety of carotenoids and, as I recollect, are
> > > > described in: Simpson K.L. Katayama T. Chichester C.O., 1981,
> > > > Carotenoids in fish feeds. In: Carotenoids as Colorants and
> > > > Vitamin A Precursors, J.C. Bauernfeind, ed., Academic press, New
> > > > York, pp 463-534. I write
> > > 'recollect'
> > > > because I do not have a copy of this chapter, but I consulted
> > > > the book in one of the academic libraries in Aberdeen and I no
> > > > longer live in that city). Chemical analysis - not too difficult
> > > > - will be able to identify if the colour is a carotenoid, and
> > > > its nature.
> > > >
> > > > Let me put forward as a hypothesis that the haddock in question
> > > > have been feeding on polychaete worms that contain a yellow
> > > > carotenoid. If you know the catching ground of the haddock, you
> > > > might be able to confirm from a marine laboratory if polychaete
> > > > worms are likely to be an item of the haddock diet. Unless they
> > > > had been feeding on corn!
> > > >
> > > > Given the known free-radical scavenging properties of
> > > > carotenoids, and the benefits to health of carotenoids in the
> > > > diet, the yellow colour should perhaps be seen as a benefit, not
> > > > a defect.
> > > >
> > > > Peter Howgate
> > > >
> > >
> > >
> >
> >
> > ____________________________________________
> > Ing. J.(Jan) A.M. Verhoeven, director of:
> > Foodfocus, consultancy- & service bureau food: technology and
> > quality
> assurance
> > De Volder 32, NL-5283 ZD BOXTEL, The Netherlands
> > tel +31 411 67 56 39 fax +31 411 67 11 56
> > E-mail info@foodfocus.nl
> > http://www.foodfocus.nl
> >
> >
>
>
____________________________________________
Ing. J.(Jan) A.M. Verhoeven, director of:
Foodfocus, consultancy- & service bureau food: technology and quality assurance
De Volder 32, NL-5283 ZD BOXTEL, The Netherlands
tel +31 411 67 56 39 fax +31 411 67 11 56
E-mail info@foodfocus.nl
http://www.foodfocus.nl
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