*  Exported from  MasterCook  *
                       SUSHI ETC. FISH AND PARASITES
 Recipe By     : 
 Serving Size  : 1    Preparation Time :0:00
 Categories    : 
   Amount  Measure       Ingredient -- Preparation Method
 --------  ------------  --------------------------------
   Notes on Sushi and Parasites
   Here are a few notes on the subject of parasites in
   fish from Tym Parsons. He asked me mention that he is
   not an expert in the subject, but these notes are
   based on his personal experience. -- Robb Satterwhite
   Since I am a fanatical lover of sushi yet not always
   willing to pay the exorbitant cost of eating it at a
   restaurant, I've learned how to prepare it at home. I
   called my local county health dept. to get some tips
   on how to detect parasites in fresh unfrozen ocean
   One thing to keep in mind is that commercially
   processed fish fillets are over a light table in order
   to screen for parasites, but that will only detect
   something no more than a half inch deep, though
   sometimes now ultra-sound is starting to be used,
   which is better.
   Anyway, I was told that there are two main kinds of
   parasites to look out for: liver flukes and nematodes.
   The flukes shouldn't be much of a problem to detect
   because they're usually the size of your thumb (I've
   never found one BTW). Nematodes are more problematic,
   since they can be as small as three-quarters of an
   inch long and two diameters of a human hair in width.
   They tend to have a white translucent sheen (which
   isn't so helpful, since so is a lot of connective
   tissue) but are _perpendicular_ to the muscle
   striations, since they bore into the muscle. Also
   check for odd things lodged between the skin and the
   flesh. And the more experience you've had examining
   the fish the more you learn to tell what’s normal and
   what’s not. “When in doubt, throw it out.”
   In any case, I understand there are only a couple
   dozen cases a year from fish parasite infestation in
   the _whole_ U.S., usually due to people who prepare
   raw fish at home but don't know what to look for. And
   even then I understand the parasites usually get
   coughed up maybe twenty four hours later. So the risks
   involved (at least for me) are negligible relative to
   the benefit.
   Tym Parsons
   Stephen Craig Sickles wrote: I read with great
   interest your posting about home sushi-making, because
   I too have recently decided to try and break the sushi
   restaurant 'tyranny' over preparation and pocketbook.
   :) I would love to hear more about your experiences,
   particularly: 1) Where do you purchase the fish you
   use? Fresh fish that is flown in daily can be had at
   most large supermarkets in large cities across the
   U.S. nowadays (see qualifications below). 2) Do you
   ever freeze it (a good method, I've heard, for killing
   all parasites)? If you freeze it 24-48 hrs. (differing
   accounts I've read) it will kill the parasites.
   Unfortunately that makes it no longer “fresh”, and
   there is a discernable difference in taste and
   texture. 3) Do you have any 'hints' on selection and
   purchase? The general rule for freshness is: does it
   smell like a “sweet ocean breeze” rather than “fishy”
   or like ammonia; are the eyes clear rather than dull;
   when you poke at it does the flesh bounce back up or
   stay depressed; is there any sign of oxidation
   (browning) of the flesh; is the flesh firm or are
   there gaps developing. As far as purchase, get only
   that which is advertised as “fresh” (That means it
   can't have been frozen, by law). Even then, oftentimes
   it will have been sitting in the case for a few days,
   so it’s good to ask when it actually came in. And even
   then, you'll often get a vague or dissembling reply.
   So it’s a good idea to get to know your fish-monger,
   or at least ask, “what do you particularly ecommend
   today?” 4) What are the 'safer' (less parasitic) fish
   to use as a starting point? ....Snapper or rockfish is
   a good bet. Tuna is a bit more problematic, and I've
   found some oddities. “When in doubt, throw it out.” I
   love mackerel, but I've found parasites there too, and
   it tends to degenerate quickly. *Definitely* do not
   use fresh cod or herring or freshwater fish. I know
   someone who worked on a fishing boat in Alaska and he
   said that cod are absolutely riddled with parasites.
   I've never seen it at a sushi bar at any rate. 5) Are
   there any books on selection/preparation that you
   recommend? The book that I have, “Quick & Easy Sushi
   Cook Book” by Heihachiro Tohyama and Yukiko Moriyama
   is a good one, tells you how to make everything from
   scratch if need be (like eelsauce). Tracking down a
   book can be difficult. I'd look in Asian grocery
   stores. My main interest is sashimi, and I was
   considering asking my sushi chef if I could accompany
   him next time he goes to market. I think it would be a
   great learning experience, and quite a bit of fun too.
   BTW, he once told me that if a fish has NO parasites,
   he is a little suspect of it. It seems that parasites
   rarely attack diseased fish. I don't tell this story
   often, because people who have never tried sushi may
   get the wrong impression, but it makes a little sense.
   Um, maybe. Sounds a little hyperbolic to me though ;).
   I want to emphasise that I don't presume to be a
   “sushi authority” here. The foregoing is based on my
   experience of four years making sushi (with no ill
   effects), and recollection of what I've read. I
   welcome any corrections from anyone who’s in a better
   position to know.
   Tym Parsons
   Recipe By     : Tokyo Food page on the Web
                    - - - - - - - - - - - - - - - - - -