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Cooked Fruit, Standing Firm

It’s a culinary dilemma: cooking typically brings out food’s fullest flavor, and fruits are most flavorful when they’re ripe; however, when fruits are ripe, they are also most difficult to cook successfully. Baked apples can turn into applesauce. A poached peach may look like peach preserves. Cooking fruit without reducing it to pulp is an art—an art that benefits from a little applied food science.

Ripening: Nature’s Sweetest Trick
A look at how fruits ripen shows how they come to this challenging state.

Ripening is nature’s way of ensuring that plants reproduce. Fruits are designed to carry and protect plant seeds. While a seed matures, hormones bring about changes in the fruit’s structure. As in humans, plant hormones are chemical compounds that help regulate growth processes. Fruit grows as hormones make its cell walls more elastic and expandable. Other hormones break down chlorophyll, allowing bright, appealing colors to develop. Hormones decrease the acidity of the juice and convert complex carbohydrates in the tissue into sweeter simple sugars. They also trigger the formation of aromatic, flavorful compounds. The hormone gas ethylene prompts the production of an enzyme that breaks down the fibers and pectin to soften the fruit. Pectin is a gluey starch that supports cell walls.

What is the end result of these changes? A large, eye-catching food that tastes and smells sweet and is easy to eat. The lure is tailor-made for people and animals, who bite into the fruit, drop the seeds, and scatter them into the soil. Uneaten fruits fall and decompose, accomplishing the same end.

In cooking fruit, your goal is to duplicate nature’s goal, producing a dish that is sweet and flavorful, yet firm enough to handle. Fortunately, you have a few tricks of your own to use. They are not as impressive as nature’s, but they’re effective.

Make It Short and Sweet
The main obstacles to cooking ripe fruit are its softness and high water content. Two techniques are useful for dealing with this delicate condition.

  • Cook quickly. It makes sense: the less time fruit is exposed to heat, the less chance it has to break down. If fruits are soft, choose grilling or broiling over stewing or baking. When poaching, give fruits a quick dip in the simmering bath.
  • Cook in syrup. Cooking in a highly sugared syrup helps ripe, juicy fruits hold their shape. This is due to osmosis (ahz-MOH-sus), in which water is drawn through a membrane, as in cell walls, until the percentage of dissolved matter in liquid is roughly equal on both sides. Sugar is highly osmotic (ahz-MAH-tik). If sugar is more concentrated in the water outside of the fruit, it draws water from inside the fruit to even things out.The drier fruit is less prone to breaking down. For optimum strength, add molasses or brown sugar to the syrup. These sweeteners contain calcium, which binds with pectin to reinforce cell walls.

Don’t Wait That Late
You can avoid problems associated with ripeness by cooking fruit before it reaches that stage. Mature, slightly underripe fruits are less sweet but firmer. They also have potential for cooked recipes. Simply adjust the methods already described to achieve a soft, sweet outcome.

  • Hold the sugar. Let moist heat tenderize the fruit from the outside. The higher concentration of sugar inside the fruit will draw more water in through cell walls. Add sweeteners, spices, and other flavorings near the end of the cooking time to make up for the lower level of natural sugars.
  • Go low and slow. Longer exposure to heat breaks down cell walls. In the early stages of cooking, the rising temperature also activates the enzymes that aid the process.

Remember the Pectin
To cook fruits at any stage of ripeness, you need to manage the pectin. Pectin helps keep cell walls intact, so fruits that are highest in pectin hold up best. Crispness is a good indicator. For example, Braeburn, Granny Smith, Rome, and some other apples are called “good for baking” due to their high pectin content. Pectin doesn’t always add crunch, however. Cranberries, tart cherries, grapes, and figs also have enough pectin to keep their form when cooked.

Pectin levels also vary with degree of ripening. Pectin peaks just before fruit reaches full ripeness. Plan on longer cooking times for fruit at this stage, even low-pectin fruits like mangoes and peaches.


What is the main purpose of fruit?
A)To produce food for the plant.
B)To serve as food for people and animals.
C)To produce pectin.
D)To ensure another generation of plants.

Which of the following examples shows how hormonal actions add appeal to fruit?
A)Ethylene activates an enzyme that weakens cell wall.
B)Chlorophyll helps convert energy from the sun to complex carbohydrates.
C)Simple sugars draw water through cell walls to soften fruit.
D)Pectin and other starches help fruit hold its shape.

Why does fruit ripen?
A)To nourish the plant seed.
B)To become more edible.
C)To attract insects that carry pollen and fertilize plants.
D)To balance the sugar concentration in the fruit.

Which cooking method is most likely to yield a satisfying result with underripe apricots?
A)Poaching in water.
B)Poaching in sugar syrup.

What is an advantage of cooking fruit with high levels of pectin?
A)They are naturally sweet.
B)They are more nutritious.
C)They hold their shape better.
D)They cook more quickly.

Imagine a recipe that reads: “Place apple halves in a baking dish with a little water. Sprinkle with brown sugar and bake covered for 25 minutes.” What factors in the recipe suggest that the apples will or will not hold their shape? Explain.
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