Blueberries are a powerhouse of nutrition

In searching for information about the human brain, researchers commonly use rats. While studying the effects of various fruit and vegetables on aging rats, scientists made some startling discoveries relative to the field of nutrition. For one early project, in the mid-’90s, three groups of aging rats were studied. The first group of rats ate their usual grain diet. The second group had spinach added and the third ate a diet enriched with blueberries.

Rats can swim, but they dislike water. The old rats were put into tanks of water with raised platforms. All three groups of rats swam around in the tank, looking for a way out. After awhile they discovered the raised platforms, and climbed out of the water.

When the rats were returned to the tanks for another swimming session, the first group of rats did not remember that the tank held platforms, they swam around for the same length of time looking for a way out, eventually climbing up on the platforms. The second group, the spinach-eaters, remembered the existence of platforms, but not their exact locations, it took them a shorter time to find the platforms and climb up. The third group of blueberry rats swam directly to the platforms. The research team concluded that both spinach and blueberries could help aging humans recover from short-term memory loss, although they did not know why the blueberriy diet had better results.

Over the past eight years, hundreds of projects have sprung up throughout the United States and Europe looking to find the answers to questions provoked by earlier studies. Some researchers have evolved a system using test tubes, blood and oxygen. They can measure the effect that certain foods, known to be high in anti-oxidants, have on human blood. They know, for example, that consuming 12 ounces of fresh spinach will raise a woman’s blood plasma’s anti-oxidant level significantly.

Another study showed that raising the number of daily servings of fruit and vegetables from five servings to 10 also raised anti-oxidant blood levels significantly, even though the participants were allowed to eat whatever fruits or vegetables they preferred. There was no increase beyond the 10 servings. (This is why I agree with AICR’s 10 serving recommendation and passed it along to readers.)

Today, much more is known about the chemical content of blueberries. Along with the anthocyanin, studied with the swimming rats, which seems to aid in memory loss, balance and eyesight, blueberries contain other phytochemicals such as ellagic acid, a cancer-

fighter.

Blueberries’ guercetin may help raise HDL levels (good cholesterol). It also has high levels of pectin, which lowers bad cholesterol and reduces aging-related nerve disorders.

Subsequent rat brain studies showed exactly where the brain cells are located that control balance. In humans, those cells begin to deteriorate around age 50. Spinach seems to improve middle-aged rats’ ability to balance on beams. That study did not use blueberries, but another one did, with moderate results in improved motor skills for elderly rats. Earlier this year, a European team found that blueberries played a role in good eyesight.

Through their reseach division, the United States Department of Agriculture funds scientists in anti-aging research. The USDA also supports programs directed at helping blueberry growers improve their crops. Commercial blueberry breeders need to replicate the high levels of the anthocyanin found in wild blueberries. Commercial berries, like so many fruits, have been bred to be easily harvested and shipped, to have a longer shelf lives, to be bigger and prettier. In the process, the level of anthocyanin in commercial berries has dropped to as low as one-twentieth the level in a wild berry. Commercial crops’ anthocyanin levels vary widely from season to season, from field to field.

The wild blueberry is one of the few fruits native to North America. Native Americans dried the berries and some tribes used them in making jerky. Others used the berries as a medicine. The USDA also supports research with cranberries, another native American fruit.

Even though scientists have yet to determine exactly how the chemicals in blueberries work their magic in the human body, they have built a growing body of evidence supporting the importance of blueberries in the diet. The Atkins Diet describes blueberries as “a nutritional powerhouse” with a low glycemic index and recommends incorporating them into menus at the start the ongoing weight loss phase of the diet. Atkins suggests raw blueberries. My research indicates that frozen or dried blueberries are fine, too. Heat destroys some nutrients, so blueberry jam or blueberry muffins would not be as nutritious as a 1/2 cup of blueberries mixed into your morning yogurt or cereal. Today’s recipes present three new ways to incorporate the nutritional power of blueberries into your diet.

Write Lynn Duvall at boblynn@ix.netcom.com.

Grilled Chicken with Blueberry-Onion Relish ]

4 skinless, boneless chicken breasts (about one pound)

Marinade:

1/2 cup orange juice

1/2 Tablespoon canola oil

1 small bay leaf 2 sprigs fresh rosemary, thyme or oregano (or 1/2 teaspoon dried)

2 cloves garlic, finely minced

Relish:

Canola oil spray

2 medium onions

1/2 teaspoon salt

1/4 teaspoon freshly ground black pepper

1/4 cup sherry

2 Tablespoons balsamic vinegar

1 cup fresh or frozen blueberries

1 cup chopped cherry tomatoes

Make marinade for the chicken by mixing together (in a non-metal container) the orange juice, oil, bay leaf, herbs and garlic. Add chicken, cover and marinate in the fridge for at least 30 minutes or up to 3 hours.

Turn chicken occasionally to distribute flavors evenly. When ready to grill, drain chicken and pat dry with paper towels. Discard marinade.

While chicken is marinating, make relish by cutting onions in half, then cut each half crosswise in thirds, cut each third into thin slices. Spray a large skillet with canola oil and heat over medium-high heat. Add onions, salt, and pepper. Cook for about 10 minutes or until onions are golden, stirring occasionally. Add sherry, vinegar, blueberries and tomatoes. Bring to a boil, immediately reduce heat to low and simmer gently for 3 to 4 minutes. Remove from heat and transfer to serving bowl.

Prepare grill for cooking, rinse chicken, pat dry. Spray chicken lightly with canola oil spray and season with salt and pepper. Grill about 5 to 6 inches from heat source until cooked though, about 4 to 5 minutes per side. Serve with blueberry relish. Serves 4. (low carb, low fat, high protein)

Adapted from AICR recipe files.

Blueberry Sangria ]

1-1/2 cups ready-to-serve blueberry juice

1-1/2 cups chilled white wine or apple juice

1/4 cup orange-flavored liqueur, optional

1 orange, sliced 1 lemon, sliced

1 cup fresh blueberries

1-1/2 cups chilled lemon-lime soda, such as Sprite

Combine blueberry juice, wine or apple juice and liqueur, if used, in a 2-quart pitcher. Add orange and lemon slices and fresh blueberries. Chill until ready to serve. Just before serving stir in soda. Serve in tall glasses over ice cubes, if desired.

Serves 6. (Makes about 1 quart liquid)

Courtesy: U.S. Highbush Blueberry Council

Blueberry & Citrus Sorbet ‘Layer Cake’ ]

1/2 cup finely chopped walnuts

1/4 cup plus 2 Tablespoons blueberry preserves or jam, divided

1 pint orange sorbet, slightly softened

1 pint lemon or other citrus sorbet, slightly softened

1 cup fresh blueberries

Line the bottom and sides of an 8 x 4-inch loaf pan with a double layer of waxed paper, folding the paper to fit smoothly. In a small bowl, stir together walnuts and 1/4 cup of the blueberry preserves; set aside. Spoon orange sorbet into the lined pan, smoothing the top to make an even layer. Spread the reserved walnut-preserves mixture evenly over the orange sorbet. Spoon the lemon sorbet evenly over the preserves and smooth the top. Cover tightly with aluminum foil. Freeze several hours or overnight.

Just before serving, in a medium bowl, stir remaining 2 tablespoons preserves until smooth; fold in fresh blueberries. Invert the cake onto a chilled serving plate. Remove the pan and waxed paper; spoon about one-fourth of the blueberry mixture down the center of the cake. Cut the cake into 8 (1-inch) slices. Serve on chilled dessert plates; top each slice with a spoonful of the remaining fresh berry mixture. Serve immediately. Serves 8.