Scientists Designing Fish for Better Taste, Nutrition

Jan. 8, 2003 -- Researchers at Purdue University are creating designer diets for farm-raised fish that could make fish healthier and tastier for humans to eat.

That's good news, considering the avalanche of reports in recent years from organizations like the American Heart Association and the National Academy of Sciences showing that a regular diet of fish, even if it's just once or twice a week, could help stave off heart disease and several other crippling illnesses.

Don't get your hopes up too soon, though. They aren't even close to making a catfish taste like a hot fudge sundae, or a Big Mac, but according to Paul Brown, a "nutritional aquaculturalist" who is leading the research team at Purdue, they're figuring out how to make it much more palatable.

"If the consumer will tell us what they want in a fish, we can make it taste that way," says Brown, a forestry and natural resources professor at Purdue.

Fattier Fish

Of course, making fish taste better isn't the primary goal of the research. What Brown and his colleagues are putting the most effort into is enhancing the package of natural fatty acids that make fish so beneficial to the human diet.

Some fish, especially mackerel, lake trout, herring, sardines, albacore tuna and salmon, contain two types of fatty acids called Omega-3s that protect against heart disease, according to a recent report by the American Heart Association. The acids make the blood less likely to form clots that cause heart attacks, and they protect against irregular heartbeats that cause sudden cardiac death, according to the study.

Omega-3 fatty acids also help bones grow, according to other research at Purdue.

Fish naturally have those acids, and in fact need them for their own survival, but they don't have another kind of fatty acid, called conjugated linoleic acid, which research has shown can help fight against certain cancers and diabetes.

Discovery of the health benefits of that particular fatty acid caused a stir a few years ago because it occurs naturally in cooked ground round, and health officials worried that might send the wrong message, leading to even greater consumption of beef. It does not occur naturally in fish.

And that's something Brown and his colleagues are trying to change.

"We're just seeing if we can put it into fish, and at what levels fish can retain it, and what happens to the other N-3 fatty acids that we would also like to keep in the fish because of their health benefits," he says.

Two very different species are being tested, a hybrid striped bass and the yellow perch, and so far the experiment has been a resounding success, according to Brown.

Fishy Tasting

"It's retained at very high levels [in both species], he says, much higher even than in cattle where it is normally found.

But does it affect the taste?

Brown says he doesn't know yet. It seems that nobody in the lab had taken a bite out of one of the fishy participants in the study.

However, it seems reasonable to assume that even the perch, noted for its mild taste, would taste, well, fishier. The diet consists of more fatty acids, which make the fish fatter, and consequently fishier.

But that shouldn't be a problem, Brown insists.

It turns out that fish prove that old axiom, "we are what we eat."

By simply modifying the diet in the two or three weeks before the fish is transferred from the pond to the barbecue, Brown insists that he can make it taste better.

"It's just a function of what we feed it," he says. "We can make a fish taste fishier [by giving it more fish meal], or milder [by giving it more soy beans]."

In fact, he adds, he can make it pretty boring.

"Some people call it bland, like chicken," he says.

Farm-Raised Mushy

Brown might be able to make it taste better, but most fish lovers will tell you that some farm-raised fish, like salmon, have a different texture than wild fish. In a word, it's mushy.

Apparently, farm-raised fish don't have to work as hard as wild salmon, so they don't get enough exercise to make them a tad tougher. And they are fed a lot of fat to make them grow quickly.

But some species, he insists, seem to thrive on the farm.

"We did a series of taste tests at four different state fairs, and the farm-raised perch was preferred over the wild perch by a wide margin," Brown says.

But, chances are, some folks are going to be hard to convince, especially young people who so desperately need to break away from fast food and develop a taste for fish. A small serving of salmon, about the size of a deck of cards, can have a major impact on human heath if consumed once or twice a week, according to new guidelines put out by the American Heart Association.

There would be no problem, of course, if Brown and his colleagues could figure out how to make a sardine taste like a bag of french fries. Wouldn't mind having one of those puppies myself.

Lee Dye’s column appears weekly on ABCNEWS.com. A former science writer for the Los Angeles Times, he now lives in Juneau, Alaska.