3.2.5: Selecting, Purchasing, Storing and Preparing Fruits

Selecting Fresh Fruits

Fresh fruits have not been subjected to any processing (such as canning, freezing or drying). Fresh fruits may be ripe or unripe, depending on their condition when harvested or the conditions under which they have been stored. In order to use fresh fruits to their best advantage, it is important to make careful purchasing decisions. It is important to pay attention to the size of each piece of fruit, its grade or quality, its ripeness on delivery,and its nutritional content in order to serve fruit in an appropriate and cost-effective manner.

Grading

Fresh fruits traded on the wholesale market may be graded under the USDA's voluntary program. The grades, based on size and uniformity of shape, color,and texture as well as the absence of defects, are U.S. Fancy, U.S. No. 1, U.S. No. 2 and U.S. No. 3. Most fruits purchased for food service operations are U.S. Fancy. Fruits with lower grades are suitable for processing into sauces, jams, jellies or preserves.

Ripening

Several important changes take place in fruit as it ripens. The fruit reaches its full size; its pulp or flesh becomes soft and tender; its color changes. In addition, the fruit's acid content declines, making it less tart, and its starch content converts into the sugars fructose and glucose, which provide the fruit's sweetness, flavo, and aroma.

Unfortunately, these changes do not stop when the fruit reaches its peak of ripeness. Rather, they continue, deteriorating the fruit's texture and flavor and eventually causing spoilage. Depending on the species, fresh fruits can be purchased either fully ripened or unripened. Figs and pineapples, for example, ripen only on the plant and are harvested at or just before their peak of ripeness, then rushed to market. They should not be purchased unripened, as they will never attain full flavor or texture after harvesting. On the other hand, some fruits, including bananas and pears, continue to ripen after harvesting and can be purchased unripened.

Gas

With most harvested fruits, the ripening time as well as the time during which the fruits remain at their peak of ripeness can be manipulated. For instance, ripening can be delayed by chilling. Chilling slows the fruit's respiration rate (fruits, like animals, consume oxygen and expel carbon dioxide). The slower the respiration rate, the slower the conversion of starch to sugar. For quicker ripening, fruit can be stored at room temperature.

Ethylene

Ripening is also affected by ethylene gas, a colorless, odorless hydrocarbon gas. Ethylene gas is naturally emitted by ripening fruits and can be used to encourage further ripening in most fruits. Apples, tomatoes, melons, and bananas give off the most ethylene and should be stored away from delicate fruits and vegetables, especially greens. Fruits that are picked and shipped unripened can be exposed to ethylene gas to induce ripening just before sale. Conversely, to extend the life of ripe fruits a day or two, isolate them from other fruits and keep them well chilled.

Fresh fruits will not ripen further once they are cooked or processed. The cooking or processing method applied, however, may soften the fruits or add flavor.

Purchasing Specifications

Fresh fruits are sold by weight or by count. They are packed in containers referred to as crates, bushels, cartons, cases, lugs or flats. The weight or count packed in each of these containers varies depending on the type of fruit, the purveyor, and the state in which the fruits were packed. For example, Texas citrus is packed in cartons equal to 7/10 of a bushel; Florida citrus is packed in cartons equal to 1/s of a bushel. Sometimes fruit size must be specified when ordering. A 30-pound case of lemons, for example, may contain 96, 112, or 144 individual lemons, depending on their size.

Some fresh fruits, especially melons, pineapples, peaches, and berries are available trimmed, cleaned, peeled, or cut. Sugar and preservatives are sometimes added. They are sold in bulk containers, sometimes packed in water. These items offer a consistent product with a significant reduction in labor costs. The purchase price may be greater than that for fresh fruits, and flavor, freshness, and nutritional qualities may suffer somewhat from the processing.

Purchasing and Storing Preserved Fruits

Preservation techniques are designed to extend the shelf life of fruits in essentially fresh form. These methods include irradiation, acidulation, canning, freezing, and drying. Except for drying, these techniques do not substantially change the fruits ' texture or flavor. Canning and freezing can also be used to preserve cooked fruits.

Irradiated Fruits

Some fruits can be subjected to ionizing radiation to destroy parasites, insects, and bacteria. The treatment also slows ripening without a noticeable effect on the fruits ' flavor and texture. Irradiated fruits must be labeled "treated with radiation," "treated by irradiation" or with the appropriate symbol.

Acidulation

Apples, pears, bananas, peaches, and other fruits turn brown when cut. Although this browning is commonly attributed to exposure to oxygen, it is actually caused by the reaction of enzymes. Enzymatic browning can be retarded by immersing cut fruits in an acidic solution such as lemon or orange juice. This simple technique is sometimes referred to as acidulation. Soaking fruits in water or lemon juice and water (called acidulated water) is not recommended. Unless a sufficient amount of salt or sugar is added to the water, the fruits will just become mushy. However, if enough salt or sugar is added to retain texture, the flavor will be affected.

Although most fruits are edible raw and typically served that way, some fruits can also be cooked. Commonly used cooking methods are broiling and grilling, baking, sautéing, deep-frying, poaching, simmering, and preserving.

When cooking fruits, proper care and attention are critical. Even minimal cooking can render fruits overly soft or mushy. To combat this irreversible process, sugar can be added. When fruits are cooked with sugar, the sugar will be absorbed slowly into the cells, firming the fruits. Acids (notably lemon juice) also help fruits retain their structure. (Alkalis, such as baking soda, cause the cells to break down more quickly, reducing the fruits to mush.)

There are so many different fruits with such varied responses to cooking that no one standard for doneness is appropriate. Each item should be evaluated on a recipe-by-recipe basis. Generally, however, most cooked fruits are done when they are just tender when pierced with a fork or the tip of a paring knife. Simmered fruits, such as compotes, should be softer, cooked just to the point of disintegration. Avoid overcooking fruits by remembering that some carryover cooking will occur through the residual heat contained in the foods. Always rely on subjective tests such as sight, feel, taste, and aroma-rather than cooking time.

Cooking Methods:

Broiling and Grilling

Fruits are usually broiled or grilled just long enough to caramelize sugars; cooking must be done quickly in order to avoid breaking down the fruits' structure. Good fruits to broil or grill are pineapples, apples, grapefruits, bananas, persimmons and peaches. The fruits may be cut into slices, chunks or halves as appropriate. A coating of sugar, honey or liqueur adds flavor, as do lemon juice, cinnamon and ginger.

When broiling fruits, use an oiled sheet pan or broiling platter. When grilling fruits, use a clean grill grate or thread the pieces onto skewers. Only thick fruit slices will need to be turned or rotated to heat fully. Broiled or grilled fruits can be served alone, as an accompaniment to meat, fish or poultry or as topping for ice creams or custards.

Procedure to Broil or Grill Fruit

1. Select ripe fruits and peel, core or slice as necessary.
2. Top with sugar or honey to add flavor and aid caramelization.
3. Place the fruits on the broiler platter, sheet pan or grill grate.
4. Broil or grill at high temperatures, turning as necessary to heat the fruits thoroughly but quickly.

Baking

After washing, peeling, coring or pitting, most pomes, stone fruits,  and tropical fruits can be baked to create hot, flavorful desserts. Fruits with sturdy skins, particularly apples and pears, are excellent for baking alone, as their skin (peel) holds in moisture and flavor. They can also be used as edible containers by filling the cavity left by coring with a variety of sweet or savory mixtures.

Combinations of fruits can bake together successfully; try mixing fruits for a balance of sweetness and tartness (for example, strawberries with rhubarb or apples with plums).

Several baked desserts are simply fruits (fresh, frozen, or canned) topped with a crust (called a cobbler), strudel (called a crumple or crisp) or batter (called a buckle). Fruits, sometimes poached first, can also bake in a wrapper of puff pastry, flaky dough or phyllo dough to produce an elegant dessert.

Procedure for Baking Fruit

1. Select ripe but firm fruits and peel, core, pit or slice as necessary.
2. Add sugar or any flavorings.
3. Wrap the fruits in pastry dough if desired, or directed in the recipe.
4. Place the fruits in a baking dish and bake uncovered in a moderate oven until tender or properly browned.

Sautéing

Fruits develop a rich, syrupy flavor when sautéed briefly in butter, sugar and, if desired, spices or liqueur. Cherries, bananas, apples, pears and pineapples are good choices. They should be peeled, cored and seeded as necessary and cut into uniform-size pieces before sautéing.

For dessert, fruits are sautéed with sugar to create a caramelized glaze or syrup. The fruits and syrup can be used to fill crepes or to top sponge cakes or ice creams. Liquor may be added and the mixture flamed (flambéed) in front of diners.

For savory mixtures, onions, shallots or garlic are often added. In both sweet and savory fruit sautés, the fat used should be the most appropriate for the finished product. Butter and bacon fat are typical choices.

Procedure for Sautéing Fruits

1. Peel, pit and core the fruits as necessary and cut into uniform-size pieces.
2. Melt the fat in a hot sauté pan.
3. Add the fruit pieces and any flavoring ingredients. Do not crowd the pan, as this will ca use the fruit to stew in its own juices.
4. Cook quickly over high heat.

Deep-Frying

Few fruits are suitable for deep-frying. Apples, bananas, pears, pineapples and firm peaches mixed in or coated with batter, however, produce fine results. These fruits should be peeled, cored, seeded, and cut into evenly-sized slices or chunks. They may also need to be dried with paper towels so that the batter or coating can adhere.

Fruit fritters are also a popular snack or dessert item. Fritters contain diced or chopped fish, shellfish, vegetables, or fruits bound together with a thick batter and deep-fried. Because frying time is very short, the main ingredient is usually precooked. Fritters are spooned or dropped directly into the hot fat; they form a crust as they cook. Popular examples are clam fritters, corn fritters, artichoke fritters, and apple fritters.

Method for Deep-Frying Fruit Fritters

1. Cut, chop and otherwise prepare the food to be made into fritters.
2. Precook any ingredients if necessary.
3. Prepare the batter as directed.
4. Scoop the fritters into deep fat at 350°F (180°C), using the swimming method.
5. Cook until clone. The fritters should be golden brown on the outside and moist but set on the inside.
6. Remove the fritters from the fat and hold them over the fryer, allowing the excess fat to drain off. Transfer the food to a hotel pan either lined with absorbent paper or fitted with a rack. Serve hot.
7. If the fritters are to be held for later service, place them under a heat lamp.

Poaching

One of the more popular cooking methods for fruits is poaching. Poaching softens and tenderizes fruits and infuses them with additional flavors such as spices or wine. Poached fruits can be served hot or cold and used in tarts or pastries or as an accompaniment to meat or poultry dishes.

The poaching liquid can be water, wine, liquor or sugar syrup. (As noted earlier, sugar helps fruits keep their shape, although it takes longer to tenderize fruits poached in sugar syrup.) The low poaching temperature (185°F/85°C) allows fruits to soften gradually. The agitation created at higher temperatures would damage them.

Cooked fruits should be allowed to cool in the flavored poaching liquid or syrup. Most poaching liquids can be used repeatedly. If they contain sufficient sugar, they can be reduced to a sauce or glaze to accompany the poached fruits.

Procedure for Poaching Fruits

1. Peel, core and slice the fruits as necessary.
2. In a sufficiently deep, nonreactive saucepan, combine the poaching liquid (usually water or wine) with sugar, spices, citrus zest and other ingredients as desired or as directed in the recipe.
3. Submerge the fruits in the liquid. Place a circle of parchment paper over the fruits to help them stay submerged.
4. Place the saucepan on the stovetop over a medium-high flame; bring to a boil.
5. As soon as the liquid boils, reduce the temperature. Simmer gently.
6. Poach until the fruits are tender enough for the tip of a small knife to be easily inserted. Cooking time depends on the type of fruit used, its ripeness and the cooking liquid.

Simmering

Simmering techniques are used to make stewed fruits and compotes. Fresh, frozen, canned and dried fruits can be simmered or stewed. As with any moist heat cooking method, simmering softens and tenderizes fruits. The liquid used can be water, wine or the juices naturally found in the fruits. Sugar, honey and spices may be added as desired. Stewed or simmered fruits can be served hot or cold, as a first course, a dessert or an accompaniment to meat or poultry dishes.

Method for Simmering Fruit

1. Peel, core, pit and slice the fruits as necessary.
2. Bring the fruits and cooking liquid, if used, to a simmer. Cook until the fruit is tender.
3. Add sugar or other sweeteners as desired or as directed in the recipe.

Preserving

Fresh fruits can be preserved with sugar if the fruit-and-sugar mixture is concentrated by evaporation to the point that microbial spoilage cannot occur. The added sugar also retards the growth of, but does not destroy, microorganisms.

Pectin, a substance present in varying amounts in all fruits, can cause cooked fruits to form a semisolid mass known as a gel. Fruits that are visually unattractive but otherwise of high quality can be made into gels, which are more commonly known as jams, jellies, marmalades and preserves.

The essential ingredients of a fruit gel are fruit, pectin, acid (usually lemon juice), and sugar. They must be carefully combined in the correct ratio for the gel to form. For fruits with a low pectin content (such as strawberries) to form a gel, pectin must be added, either by adding a fruit with a high pectin content (for example, apples or quinces) or by adding packaged pectin.

Terms

• Concentrate - also known as a fruit paste or compound; a reduced fruit puree, without a gel structure, used as a flavoring
• Jam - a fruit gel made from fruit pulp and sugar
• Jelly - a fruit gel made from fruit juice and sugar
• Marmalade - a citrus jelly that also contains unpeeled slices of citrus fruit
• Preserve - a fruit gel that contains large pieces or whole fruits