The traditional wisdom about getting perfect sweet corn went something like this: Set a pot of water to boil. When it is roiling, go out back, pick an ear from the stalk and cook it before the sugar starts to fade.
Now, food scientists are taking some of the hurry out of the harvest. The connection between sweetness and flavor is an important one, and new breeding techniques are finding ways to keep more produce on the sweet side. These efforts, which include new varieties of melons, pineapple and other fruit as well as greater availability of sweet onions, young carrots, sweet peas and sugar snap peas, provide sprightlier flavors and play into consumers’ powerful need for sugar.
The produce in American markets varies in quality for different reasons. Much of what we eat–certainly in the winter months–comes from quite a distance or is held in major distribution centers for days before reaching the market. Because of this, many modern growers breed produce to survive the transition from field to table, with only a secondary emphasis on flavor.
At the same time, consumers have steadily developed a taste for ever-sweeter foods of all kinds, and may be less interested in fruits and vegetables that lack the sweet flavor of other processed foods.
To meet these challenges, new propagation techniques are providing greater and longer-lasting sugar levels in produce. Although corn typically starts converting its sugar to starch after about 30 minutes, Southern Supersweet corn from Florida, for instance, retains its sugar up to 10 days after picking.
Growers also are targeting melons for a sugar high, according to Keith Mayberry, vegetable specialist and farm adviser for the University of California. Breeding programs have produced very sweet watermelons and cantaloupes, and a honeydew melon “with more sugar than Coca-Cola,” he says.
Traditional breeding methods and biotechnology both emphasize the role sweet flavor has in making produce taste better.
Food marketers say that consumers associate sweetness in produce with freshness, mainly because over-the-hill vegetables taste starchy and bitter. Conversely, fruit that has been picked and consumed before it has ripened properly, or has been handled poorly, can lose much of its sweet potential. Shoppers know this all too well in their annual search for genuinely sweet strawberries, peaches and other delicate fruits.
“More growers are trying to focus on flavor,” says Ben Wood, editor of The Packer, a produce industry trade publication based in Kansas. “For too long, many products were viewed in how they would handle the trip to market, and they were bred more for durability and shelf life. But now that we can get any (produce) year-round, there is a lot more choice and a wider variety, and people are looking for flavor.”
Peter Testa, owner of Testa Produce, a wholesaler in Chicago, cites examples of the new extra-sweet produce. The Pango Mango is a sweeter, orange-fleshed mango from Puerto Rico; “apriums” are a cross between apricots and plums; the Del Monte Gold pineapple combines a deeper color with sweeter flesh; and grape tomatoes are tiny and sweet.
“The grape tomatoes are a great hit,” Testa says. “I think eventually they will take the place of cherry tomatoes for consumers.”
In the onion bins, what used to be strictly regional treasures–Walla Walla onions from Washington, Vidalia onions from Georgia, Maui onions from Hawaii and Texas 1015s–have found favor with consumers across the country.
Food technologists point out that the new varieties of produce are not pumped with added sweeteners, but rather are grown in such a way that the inherent sugar content is enhanced. The Del Monte Gold pineapple and the Pango Mango, for instance, are bred so that they are beautifully ripe at the market, while the sweetness of their relatives on store shelves may be more hit-or-miss.
Sometimes the sweetness level in produce is a byproduct of efforts to simply reduce bitter flavors. For example, sweet onion varieties have been bred to have fewer of the pungent enzymes that make us cry when cutting regular yellow and white onions, Mayberry says. Certain citrus fruit, such as tangerines and grapefruit, are being bred to contain less acid.
In any case, consumer tolerance for lackluster produce has lowered.
“Consumers are interested in an exciting, dazzling palate,” says Mark R. McLellan, director of the Institute of Food Science and Engineering at Texas A & M University. “You can go all the way back to early man, when deposits of salt were considered absolutely precious because it would add zip to the diet. Sweetness too,” is prized, he says, “because the alternative is a fairly bland taste.” Sweet foods were naturally inviting, especially once early man discovered that many bitter foods also were toxic.
Biologists always have suspected that the taste preference for sweet is innate. At the annual meeting of the American Chemical Society in March, researchers at the Monell Chemical Senses Center in Philadelphia said they were close to identifying the gene that regulates sweet perception. It could be genetics that determines your preference for bittersweet or milk chocolate, said Monell director Gary Beauchamp.
Today, the preference for sugar also relates to the amount of added sugar Americans are used to in their diets of processed foods, sodas and desserts. Given the overload of sweeteners in the American diet, food experts and nutritionists might be expected to frown on the attempts to give produce a candylike gloss.
But not every nutritionist feels that way, says Chris Rosenbloom, an Atlanta-based nutritionist and spokeswoman for the American Dietetic Association. In fact, she says, nutritionists are lately more concerned about those consumers on sugar- and carbohydrate-restricted diets who are eliminating many naturally sweet foods altogether.
“We would rather see consumers get that sugar fix from fruits and vegetables,” than from refined sugar, Rosenbloom says. “There are so many benefits to eating fresh produce that if this is a gimmick or a hook, it’s fine.”
“I’m in favor of anything that makes people eat fruits and vegetables,” says Dr. Louis Aronne, clinical professor of medicine at Cornell Medical College in New York. “It’s hard to compete with candy. My personal opinion is that sweet foods lead to obesity, but in general, (sweeter produce) would be better if it would make people switch to a potentially healthier choice.”
The sweetness of fruits and vegetables is measured by what is called the Brix scale. Named for a 19th Century German chemist, the Brix scale measures the concentration of soluble sugars–such as fructose, dextrose and glucose–in foods.
Food scientists are trying to make produce with enough potential sugar at the time of picking to survive transportation and storage times. They want the natural sweetness to predominate even when produce is far afield.
Even varieties with naturally high Brix levels can turn sour during growing. Poor soil, a lack of sun and other conditions can affect produce before it is even picked.
Jon Rowley, a food marketing consultant in Seattle who has made a name for himself as a seafood expert, has been examining the loss of flavor in fresh fruits and vegetables for almost 20 years. He’s writing a book on Brix content in produce.
“Peaches are the item stores get the most complaints about,” Rowley says, “so over a two-year period I logged about 2,000 miles going through the peach orchards of the West Coast.
“I noticed that a certain variety, grown at the same time on different farms, had Brix levels that were all over the board, and the color and quality and aroma were all different.”
Scientists are working on ways to make those peaches, or corn or melons, taste consistently sweet; no matter where they are grown or how far they are shipped. If they are successful, the next sugar high will be from the produce bins, not the candy aisles.
HANDLE WITH CARE
Handling alters the quality and flavor of produce too. Most fruits and vegetables make a journey from the tree, vine or soil to a packer, then to a shipper, a distribution warehouse, the store and finally, the kitchen. Produce picked when perfectly ripe would be ready to spoil by the time it reached the last stop, so growers get their wares picked early, and try to ensure they ripen along the way.
That’s because errors in handling or temperature fluctuations during storage can damage the produce even before it reaches consumers. Stacked fruit, such as apples, can begin bruising even before the discoloration is apparent, says produce wholesaler Peter Testa. Ripening fruit, such as bananas or peaches, produce ethylene gas that can toughen neighboring asparagus and broccoli, causing yellowing and off-flavors, says Keith Mayberry, a California farm adviser.
And that’s before consumers get their hands on them, says Testa, recalling the sight of shoppers slinging bags of fruit onto scales and checkout counters at the supermarket.
“Produce doesn’t take well to handling and dropping,” Testa says. “Squeezing is OK, but you don’t have to give it a death grip.”
If you can’t shorten the distance between the soil and the kitchen table by growing produce at home, treat the produce the way you would anything you were hoping to coax a little sweetness from: Gently.
ROASTED SWEET CORN AND CHICKEN-APPLE SAUSAGE RISOTTO
Preparation time: 20 minutes
Cooking time: 50 minutes
Yield: 4 servings
Roasting corn in the oven until golden brown and slightly chewy enhances its natural sweetness, even when you start with frozen corn. Play up the sweet-savory flavors of this dish by using a mild, not spicy, sausage. Developed in the Tribune test kitchen.
2 1/2 cups fresh or frozen corn
1/4 cup olive oil
9 ounces chicken apple sausage links or other sausage
3 tablespoons unsalted butter
2 large shallots, diced
2 cups arborio rice
3/4 cup white wine
5 cups chicken broth, heated
1/3 cup grated Parmesan cheese
Salt, freshly ground pepper, chopped parsley
1. Heat oven to 350 degrees. Place corn on baking sheet; toss with 2 tablespoons of the olive oil. Spread corn out evenly. Roast 25 minutes. Remove; set aside. Meanwhile, cook sausage in skillet, turning often, until cooked through, about 8 minutes. Slice into 1/4-inch pieces; set aside.
2. Heat 1 tablespoon of the butter and remaining 2 tablespoons olive oil in large, heavy-bottomed saucepan or Dutch oven over medium-high heat. Add shallots; cook, stirring, 1 minute, until translucent. Stir in rice until well coated. Pour in wine; cook until wine evaporates, 2 minutes.
3. Add warm broth, 1/2 cup at a time, stirring constantly, until broth is absorbed. Repeat with remaining broth, until rice is tender but still firm to bite, about 20 minutes. Remove from heat. Stir in corn, sausage, Parmesan and remaining 2 tablespoons butter. Season with salt and pepper. Garnish with parsley.
Nutrition information per serving:
Calories ………… 870 Fat ……….. 39 g Saturated fat .. 13 g
% calories from fat .. 40 Cholesterol .. 95 mg Sodium ….. 1,200 mg
Carbohydrates ….. 100 g Protein ……. 28 g Fiber ……… 3.8 g
PINEAPPLE CAKE WITH WARM GINGER-PINEAPPLE SALSA
Preparation time: 50 minutes
Cooking time: 1 hour
Yield: 10 servings
Sugary fresh pineapple is nicely balanced in this not-too-sweet cake, adapted from “Allen Susser’s New World Cuisine and Cookery.” The feather-light texture of the cake is well paired with the pineapple salsa. Fresh ginger and star anise give the salsa a mysterious edge; look for star anise in Asian groceries or specialty markets.
Cake:
2 sticks (1 cup) unsalted butter, softened
1/2 cup sugar
3/4 cup pure maple syrup
3 large eggs, separated
1 teaspoon vanilla extract
2 1/2 cups cake flour, sifted
1 tablespoon baking powder
1 teaspoon ground cinnamon
1/2 teaspoon salt
1/3 cup whole milk
1 cup diced fresh pineapple
Ginger-pineapple salsa:
3 tablespoons unsalted butter
1/2 cup light brown sugar
1 teaspoon minced fresh ginger
1/2 teaspoon each: ground cinnamon, vanilla extract
Pinch sea salt
1 piece star anise, crushed
2 cups diced fresh pineapple
1/2 cup macadamia nuts, chopped, toasted, see note
1. Heat oven to 350 degrees. For cake, beat butter in bowl of electric mixer on high speed until pale and fluffy, 3-4 minutes. Add sugar and syrup; beat until well mixed. Scrape down sides of bowl. Beat in egg yolks one at a time until well mixed, scraping down sides of bowl between yolks. Beat in vanilla.
2. Combine flour, baking powder, cinnamon and salt in medium bowl. Add to butter mixture alternately with milk in three stages; mix well. Add pineapple.
3. Beat egg whites in clean bowl of electric mixer until stiff but not dry; fold into batter in three stages. Line greased and lightly floured 10-by-8-inch loaf pan or 10-inch tube pan with greased parchment paper or wax paper; pour in batter. Bake until cake tester comes out clean, about 1 hour. Place pan on wire rack to cool 15 minutes; unmold cake onto wire rack. Cool completely before removing paper.
4. For salsa, melt butter in large skillet over medium heat. Add brown sugar and ginger; cook 1 minute. Stir in cinnamon, vanilla, salt and star anise; mix well. Add pineapple and nuts; cook until warmed through, 3-4 minutes. Slice cake. Serve with warm salsa.
Note: To toast macadamia nuts, heat skillet over medium heat. Add nuts. Cook, stirring often, until nuts are lightly brown and begin to release their fragrance, about 4 minutes.
Nutrition information per serving:
Calories ………… 525 Fat ………… 29 g Saturated fat .. 15 g
% calories from fat .. 49 Cholesterol .. 125 mg Sodium ……. 310 mg
Carbohydrates …… 64 g Protein ……… 5 g Fiber ……… 1.9 g
