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This question didn't come via AskDrGourmet@drgourmet.com but was asked recently during a conversation that I was having with someone using one of the meal plans in my books (there are plans, all based on a Mediterranean style diet, for those taking Coumadin, who have GERD, or need a Low Sodium Diet.)
She was asking about the number of seafood meals. Her concern wasn't how much fish she would be eating (and those of you who often read these columns know that eating seafood is really good for you) - she was concerned about storing fish and shellfish, telling me that she couldn't get to the fish store in her area every night because she works until after it closes at 6:30. She had to buy fish a day or two before cooking it, so how could she store it so that it stayed fresh?
Storing fish is something that I know a lot about, because when I first moved to Northern Virginia in 1994 I lived far enough outside of Washington, D.C. that good quality fish wasn't available in my small town. This isn't as much of an issue as it used to be, but at the time I would drive an hour each way twice a week to shop for quality meats and fish.
The first step to storing fish is to buy the freshest fish possible. If you are in a large city, make friends with a fish monger or at a specialty grocery like Whole Foods. Ask them when the fish came in to the store and where it came from. Build a relationship so that you know you can trust them. If the fish has already been filleted, look for a clear, shiny flesh. Fish that is older will begin to take on a dull look, and fish that has been frozen will start to separate along the striations of the meat (you can see that in the bottom filet in the picture above). It takes some practice and you have to look carefully at a lot of fish, but think of fresh fish as being like clear water and less fresh as being like dishwater with a slight milky color. If the seafood smells too much of a fishy odor, it is likely older.
Once you have your fish home, it's key to 1) keep it very cold, and 2) keep it moist - but not overly so. I choose the coldest part of the refrigerator and keep my fish in plastic containers that I only use for seafood. I place a round steamer basket (the kind that folds up) in the bottom of the container, place ice in the strainer, then place the fish on top of the ice. The melting ice well drip into the bottom of the container, away from the fish.
If you aren't going to use the fish pretty quickly, place a sheet of plastic wrap over the ice to protect the fish. Because the flesh of most fish will absorb a lot of water, putting ice directly on top of the fish can harm your seafood, making it mushy.
Don't be afraid of frozen fish. While it's not "perfect," frozen fish is pretty darn good. Seafood is often flash frozen onboard the ship, or at the very least kept on ice and then frozen right after being trimmed. Much of the fish, even at specialty groceries, has been frozen anyway. For instance, the vast majority of shrimp sold has been flash frozen shortly after being caught. (We are very lucky here in New Orleans - as with other coastal cities - that finding shrimp that has not been frozen is pretty easy.)
For the most part you can keep fish fresh and great tasting very easily and safely by keeping it ice cold and moist (but not wet) for about 48 hours or so after you purchase it. For most of us this means that a second smaller trip to the grocery mid-week is a good idea (but it's likely that you're going anyway). As I have said before, eating great food and eating healthy is about planning and this is one of the best examples of that. It's easy and oh, so worth it.
Timothy S. Harlan, MD, FACP