Subject: Jellied Turbot/Greasy Haddock
Date: 15 January 1999
sort of jumping into the middle of a discussion here.
But when I read the recent postings on this topic, I started thinking
about a similar problem which existed in the herring industry in Denmark 3-5
years ago. A small percentage of
herring (Clupea harengus) would simply be so degraded that they couldn´t be
filleted. It was discovered that
the reason for this phenomenon was an infection with ichthyophonus hoferi and a
colleague of mine back then, Dr. Bettina Spanggaard (e-mail: firstname.lastname@example.org)
did extensive research on this problem. I.
hoferi has previously been found in Pacific waters around Japan and in various
areas of the Atlantic Ocean, and is therefore not a local problem.
This organism is also known to attack other fish such as haddock,
mackerel and plaice. Hope this may
refer to the message of 15 January from Lisbeth Hansen concerning ichthyophonus
hoferi, (this organism is, or was, also called icthyosporidium hoferi).
As Lisbeth relates, it is a parasite that occurs in several species of
fish and can affect various organs in the fish body, including the muscle.
It gives the muscle a soft, slimy texture and an offensive odour.
In Britain it is known mostly in haddock when the condition is referred
to as ´greasy haddock´. The
condition is another example of abnormal textures in fish, and should be noted
by quality controllers, but it is not the same, and has different causes from,
the chalky and the jelly conditions. An
account of the relevant, for fish technologists, part of Spanggaard´s work is
given in Spanggaard, B. and Huss, H.H. 1996 ´Growth of the fish parasite
ichthyophonus hoferi under food relevant conditions´, International Journal of
Food Science and Technology, 31, 427-432. This
provides a bibliography of other published work, including other papers by