Here in Australia the purgative properties of Escolar are known. Last year a report was produced by Nick Ruello, one of our eminent marine biologists.
Mark Boulter
QA Manager
Sydney Fish Market
Report On The Oil Content, Composition, And The Consumption Of Escolar
Prepared For The Australian Government Department Of Health and Ageing
By Ruello & Associates Pty Ltd April 2004
The conclusion in Nick Ruello's report reads;
This study indicates that there is a huge and essentially unpredictable variability in total oil and wax ester content of escolar caught on either the east or west coast. There also appears to be no significant difference between the oil content of fish on the west and east coast of Australia, for at least the summer season.
Although much remains unknown about the cause of the serious symptoms reported by some escolar consumers it is evident that fish of all sizes have very high wax ester content and may cause keriorrhoea or serious illness to some consumers at any time. Nevertheless it is noteworthy that more than a million portions of escolar are likely to be eaten each year in Australia with very few reported problems.
There was no evidence to support the belief that deep skinning the fillet reduces the wax ester content of the flesh; indeed trimming out the red muscle from the midline of the fillet is counterproductive given its relatively low oil content. The skin does have a very high oil level and it is therefore recommended that fish cutlets are skinned before sale to reduce the oil content.
There was no evidence to support the common perception that the wax esters can be "grilled out" of the fish, or otherwise substantially reduced by normal cooking methods; cooking actually "concentrates" the oil as water is expelled from the flesh. Freezing the (raw) fillet for as long as 9 months also fails to noticeably reduce the capacity of escolar to induce keriorrhoea.
There are however significant differences in oil content of different parts of the fish. The tail end is the least oiliest part of the fillet, on average, and is therefore the best cut to offer a first time buyer while the belly flesh on larger fish may be the oiliest flesh and should be eaten with greater moderation by any newcomer. Pregnant women and persons with digestive tract problems should take particular care.
The consequences of eating the fish are essentially unpredictable because of the variability in wax ester content of fish portions and the individual consumer's susceptibility or tolerance to the wax esters, which may of itself also vary from one meal to another. With the high oil content of some escolar a serve as small as 140 g has been recorded as capable of inducing keriorrhoea in some individuals.
The high variability in oil content between fish and within a single fish means that an even smaller serve of very oily flesh may have the same impact; portion size is no indicator of the oil content of the piece. The common advice to only eat a small portion of escolar if uncertain appears inadequate in the absence of sufficient data to nominate a safe portion or safe wax ester "dose"; such advisories should therefore suggest first time consumers eat only a very small portion (eg 50g) if uncertain.
Additionally, there is clearly a need for careful analysis of a consumer's account of the food and drink consumed, and all other related factors in any escolar/rudderfish/butterfish public health problems to gain a better understanding of the precise nature of the illness so that appropriate remedial action, and preventative measures, can be initiated. After all a consumer who has had such an unsettling gastrointestinal experience would hardly be at ease in divulging embarrassing or personal details to a stranger or be favourably disposed to escolar.
It may well be that the "watery diarrhoea" and other serious symptoms reported by Yohannes et al(2002), Givney (2002), Gregory (2002) and Delroy (personal communication 2004) are due to more than just the wax esters in the fish. Givney (2002) implied this and recommended "... that advice be sought to arrange testing to exclude microbiological and toxic causes". This recommendation is endorsed because without closer scrutiny of the symptoms, chemical analysis of the raw and cooked fish and microbiological analyses of stool samples there will be uncertainty.
Nevertheless there is clearly a need for trade and consumer education to raise awareness of the escolar and oil fish and the possible consequence of eating these and other species such as orange roughy; an informed consumer is less likely to be startled or frightened by keriorrhoea and probably better able to describe and manage any symptoms in case of serious illness.
Any communications program needs to cover consumers, the seafood and catering industry as well as medical practitioners and public health agencies so all can be better informed and take appropriate preventative or remedial measures as needed.
Furthermore the seafood industry needs to be more diligent, by using the correct marketing name and clearly informing its customers of the purgative qualities of these fish. Fish merchants may not be certain about the correct marketing name for escolar but most of those who sell it are aware of its purgative qualities.
Nichols et al(2001) have reported that the oil composition of true rudderfish are dominated by diacylglycerol ether (DIAGE) which does not have the purgative qualities of the wax esters. Seafood industry leaders should therefore use whatever means they have available to stop wayward colleagues from hiding escolar or oil fish behind the rudderfish or butterfish alias and to have them advise first time buyers of the possible consequences of consumption with explicit labeling.
History suggests that there will continue to be transgressors, so the pertinent authority will also need to pursue those merchants and restaurateurs who continue to deceive and endanger public health and consumer confidence in seafood.
The unusual oil profile of escolar offers opportunities for new product development which can enhance the fish's reputation and help mankind. Ukishimi et al(1987) reported that the refined wax from L. flavobrunneum was "highly safe", indicating the usefulness for a base of medicine or cosmetics. More recently and closer to home, Nichols et al(2001) reported that wax esters oils from orange roughy are being used in cleaning, degreasing and other products.
Finally, the seafood industry should encourage and support Australian medical scientists to research the purgative qualities of escolars so that the fish flesh, skeleton or skin can be put to medical use in this age of natural medicines. The good taste and purgative qualities of the flesh can then be promoted to an informed public seeking natural remedies for their individual medical conditions.
----- Original Message -----
From: Kevin JK Choi
To: Seafood research and extension information exchange
Sent: Tuesday, April 05, 2005 4:11 PM
Subject: Is "Escolar" poisonous?
Greetings Seafood List Serve,
Does anyone have any information about fish "Escolar" that they can send
to
me?
I currently have a big argument with one salesman.
He said that Escolar is poisonous without question and not allowed to
cook
for a human being. He thinks that Escolar is resulting in the violent
diarrhea every time whenever people have. He also thinks that Escolar
is
resulting in the violent diarrhea every time whenever people have.
But, I do not think so. I have tried to have this Escolar many times
before, but I was fine everytime. I like this fish, very pleasing
texture.
I know that FDA allowed to sell this fish fillets on 1994 and many
Restaurants in United States are currently selling it as the best dish a
la
carte.
Nevertheless, Is "Escolar" poisonous without question and not allowed to
cook for a human being? I believe that it will be fine, if we have just
little "Escolar" at once.
Please let me know if anyone has any opinion.
Thanks,
Kevin J.K. Choi
HANAMI FOODS CORP
Phone : 201-857-2175
201-657-3386
Fax : 201-581-0238
email : mail@hanamifood.com
This archive was generated by hypermail 2b29 : Tue Apr 05 2005 - 18:41:23 PDT