On Nutrition

DEAR DR. BLONZ: How do imitation crab meats compare with regular crab in terms of omega-3 fats? I asked my local fish store and was told that imitation crab comes from pollock, and I heard this is a low-mercury fish. I don’t buy it to pretend that it is crab; I buy it because it’s the only way that I can find pollock locally. And it is generally inexpensive, so that makes it a good buy. But does the processing of the pollock -- including the coloring and the flavor infusion -- change any of the omega-3 levels? -- F.M., Tulsa, Oklahoma

DEAR F.M.: While a good source of protein, and low in mercury, pollock is considered a moderate to low source of omega-3 fats -- comparable, actually, to that found in crab. A 3-ounce serving of Dungeness crab contains 383 milligrams of omega-3 fats, while a similar serving of Alaskan pollock contains 418 milligrams. For comparison with other fish, this is about one-fourth the level found in wild salmon.

While pollock isn’t particularly high in omega-3s to begin with, turning it into imitation shellfish (also called surimi) will reduce the levels even further. To make the fish look and taste like crab or lobster, they are typically deboned, rinsed, minced, flavored, colored and reformed to resemble the muscle fiber and taste impression of the desired variety. It is not a process that’s kind to omega-3 fats. A 3-ounce serving of surimi made from pollock will contain only 26 milligrams of omega-3 fatty acids.

DEAR DR. BLONZ: What are the nutritional consequences of discarding the liquid that separates from yogurt in the container? Since discovering Greek yogurt on my trip to Greece last year, I find I prefer the thicker consistency. However, I like to achieve this by purchasing American yogurt, allowing it to settle and then removing the liquid. However, I’m unsure whether I am losing valuable nutrients with this practice. -- A.A., Denver

DEAR A.A.: The liquid on top is mostly water, but also contains whey. Whey contains a bit of protein, some carbohydrates and a few water-soluble nutrients, including calcium, that remain in solution.

The texture of Greek-style yogurt comes from being strained to eliminate extra liquid. More liquid gets removed with Greek yogurt than from pouring out the liquid from a standard type; this explains why, even if you pour off the liquid and spoon out a serving, you will find some water there the next time you open up the container. Greek-style yogurt has less calcium, but a higher proportion of protein per weight.

But all things considered, when compared with the overall healthfulness of yogurt, the nutritional consequences of going Greek or pouring off the liquid from a standard type is not significant. Go with the type that best pleases your palate. Another yogurt plus is that it’s often better tolerated than milk by those with lactose intolerance. This is explained by the fact that active yogurt bacteria produce a lactose-digesting enzyme.

Send questions to: “On Nutrition,” Ed Blonz, c/o Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO, 64106. Send email inquiries to questions@blonz.com. Due to the volume of mail, personal replies cannot be provided.

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