Q. What's the nutritional scoop on dried fruits? I'm fussy about calories, and I know a prune has about 20, a fig about 50, and each apricot half about 8. But I also eat dried apples, pineapple, peaches and pears, and I've been unable to find the figures for these. Do you have them?
A. Remember that, as with fresh fruit, caloric content varies with size and that some dried fruits, particularly figs and prunes, come in numerous sizes. Naturally, how many calories you consume will depend on both the number of pieces you eat and the size of each.
According to data available from the U.S. Department of Agriculture, an average dried peach half contains about 30 calories, just a few less than you'd get from a whole small peach measuring 2 1/2 inches across. Apparently, large peaches were used to derive the dried-fruit estimates.
A dried pear half contains 45 calories, about what you'd get in half a fresh fruit weighing about 5 ounces. And a single apple ring has roughly 15 calories. Thus, five apple rings would be the caloric equivalent of eating a fresh apple weighing four ounces.
Information about dried pineapple is hard to come by, but logic leads us to a ballpark estimate that a small dried pineapple ring would provide the same 45 calories as the fresh piece of fruit.
The real nutritional story on dried fruit is this: It contains neither more nor fewer calories than the fresh fruit from which it comes. However, people tend to eat a number of pieces at once and thereby consume hefty numbers of calories almost without noticing. For instance, you would be unlikely to eat four apricots at one time, but could easily eat 8 dried apricot halves, downing 65 calories without batting an eye.
Q. A friend recently served freshly grated horseradish, which was much more pungent than the bottled kind. She prepared it by simply adding vinegar and it made an excellent salt-free condiment. She gave me some to take home and I put it in the fridge. How long will it keep?
A. Freshly grated horseradish will last three or four months in the refrigerator, although it won't remain as pungent as when first prepared. Grating it can make you weep even more than onions do, but it's well worth the effort in terms of flavor. A food processor will ease the task. But even if you're using one, for the sake of your eyes we recommend getting a long extension cord and moving the project outdoors.
Another suggestion: The unlikely combination of grated horseradish in vinegar mixed with applesauce makes a delicious accompaniment to boiled chicken or pot roast.
Q. I've read that iron from plant foods is absorbed less efficiently than iron from animal foods. Why is this so? Also, does tea interfere with iron absorption?
A. In your first question, we're dealing with two types of iron which the body handles differently. Heme iron, the kind in animal foods, is easily freed from the protein compound to which it's attached and is then absorbed into the lining of the GI tract. There, the iron is extricated from the rest of the molecule and is ready for absorption into the bloodstream.
Nonheme iron, on the other hand, can be hooked onto a variety of compounds in food. During digestion, it is released. But instead of remaining on its own, it rapidly forms new complexes, called chelates. The nature of the chelate determines whether or not the iron will be absorbed into the body's iron pool.
If that complex is a soluble compound and can release iron, it separates as it nears the lining of the gut. In that case, the iron will be absorbed. But if the chelate is tightly bound and insoluble, the intact iron complex will travel, unchanged, through the length of the bowel and be excreted.
As to your second question: Tannin, the compound in tea responsible for its astringent quality, is an example of a chelator that forms a tight bond with nonheme iron and thereby may affect iron absorption if taken at a meal. The actual extent of the interference depends on the presence of other components of the meal, including both ascorbic acid and meat, fish or poultry. Beyond that, some evidence indicates that when milk is added to tea, the casein in it binds the tannin and makes it less available to form iron chelates in the gut.