ClubEnsayos.com - Ensayos de Calidad, Tareas y Monografias
Buscar

Nutritional Magazine


Enviado por   •  18 de Junio de 2012  •  4.959 Palabras (20 Páginas)  •  394 Visitas

Página 1 de 20

Nutritional Magazine.

Fruits.

In broad terms, a fruit is a structure of a plant that contains its seeds. The section of a fungus that produces spores is also called a fruiting body.[1]

The term has different meanings dependent on context. In non-technical usage, such as foodpreparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state, such as apples, oranges, grapes, strawberries, juniper berriesand bananas. Seed-associated structures that do not fit these informal criteria are usually called by other names, such as vegetables, pods, nuts, ears and cones.

In the botany of flowering plants, a "fruit" is a part that derives from specific tissues of the flower, mainly one or more ovaries. Taken strictly, this definition excludes many structures that are "fruits" in the common sense of the term, such as those produced by non-flowering plants (like juniper berries, which are the seed-containing female cones of conifers.[2]) On the other hand, the botanical sense includes many structures that are not commonly called "fruits", such as beanpods, corn kernels, wheat grains, tomatoes, and many more. However, there are several variants of the biological definition of fruit that emphasize different aspects of the enormous variety that is found among plant fruits.[3]

Fruits (in either sense of the word) are the means by which many plants disseminate seeds. Many plants bearing edible fruits, in particular, coevolved with animals in a symbiotic relationship as a means for seed dispersal and nutrition, respectively; in fact, many animals (including humans to some extent) have become dependent on fruits as a source of food.[4] Fruits account for a substantial fraction of world's agricultural output, and some (such as the apple and thepomegranate) have acquired extensive cultural and symbolic meanings.

Many fruits that, in a botanical sense, are true fruits are actually treated as vegetables in cookingand food preparation, because they are not particularly sweet. These culinary vegetables includecucurbits (e.g., squash, pumpkin, and cucumber), tomatoes, peas, beans, corn, eggplant, and sweet pepper. In addition, some spices, such as allspice and chilies, are fruits, botanically speaking.[5] In contrast, occasionally a culinary "fruit" is not a true fruit in the botanical sense. For example, rhubarb is often referred to as a fruit, because it is used to make sweet desserts such as pies, though only the petiole of the rhubarb plant is edible.[6] In the culinary sense of these words, a fruit is usually any sweet-tasting plant product, especially those associated with seed(s), a vegetable is any savoury or less sweet plant product, and a nut is any hard, oily, and shelled plant product.[7]

Technically, a cereal grain is also a kind of fruit, a kind which is termed a caryopsis. However, the fruit wall is very thin, and is fused to the seed coat, so almost all of the edible grain is actually a seed. Therefore, cereal grains, such as corn, wheat andrice are better considered as edible seeds, although some references do list them as fruits.[8] Edible gymnosperm seeds are often misleadingly given fruit names, e.g.,pine nuts, ginkgo nuts, and juniper berries.

Vegetables.

The noun vegetable means an edible plant or part of a plant, but usually excludes seeds and most sweet fruit. This typically means the leaf, stem, or root of a plant but also includes some fruits as well (such as squash).

The word does not have a basis in biology; instead its meaning is largely based on culinary andcultural tradition. Therefore, the application of the word is somewhat arbitrary and subjective. For example, some people consider mushrooms to be vegetables even though they are not plants,[1][2]while others consider them a separate food category.[3]

Some vegetables can be consumed raw, some may be eaten cooked, and some must be cooked in order to be edible. Vegetables are most often cooked in savory or salty dishes. However, a few vegetables are often used in desserts and other sweet dishes, such as rhubarb pie and carrot cake.

As an adjective, the word vegetable is used in scientific and technical contexts with a different and much broader meaning, namely of "related to plants" in general, edible or not — as invegetable matter, vegetable kingdom, vegetable origin, etc.[4] The meaning of "vegetable" as "plant grown for food" was not established until the 18th century.[5]

Vegetables are eaten in a variety of ways, as part of main meals and as snacks. The nutritionalcontent of vegetables varies considerably, though generally they contain little protein or fat,[8][9]and varying proportions of vitamins such as Vitamin A, Vitamin K and Vitamin B6, provitamins,dietary minerals and carbohydrates. Vegetables contain a great variety of other phytochemicals, some of which have been claimed to have antioxidant, antibacterial, antifungal, antiviral andanticarcinogenic properties.[10][11] Some vegetables also contain fiber important for GI function. Vegetables contain important nutrients necessary for healthy hair and skin as well. A person who refrains from dairy and meat products, and eats only plants (including vegetables) is known as avegan.

However, vegetables often also contain toxins and antinutrients such as α-solanine, α-chaconine,[12] enzyme inhibitors (of cholinesterase, protease, amylase, etc.), cyanide and cyanide precursors, oxalic acid, and more.[13] Depending on the concentration, such compounds may reduce the edibility, nutritional value, and health benefits of dietary vegetables. Cooking and/or other processing may be necessary to eliminate or reduce them.

Diets containing recommended amounts of fruits and vegetables may help lower the risk of heart diseases and type 2 diabetes. These diets may also protect against some cancers and decrease bone loss. The potassium provided by both fruits and vegetables may help prevent the formation of kidney stones.

For food safety, the CDC recommends proper fruit handling and preparation to reduce the risk offood contamination and foodborne illness. Fresh fruits and vegetables should be carefully selected. At the store, they should not be damaged or bruised and pre-cut pieces should be refrigerated or surrounded by ice. All fruits and vegetables should be rinsed before eating. This recommendation also applies to produce with rinds or skins that are not eaten. It should be done just before preparing or eating to avoid premature spoilage. Fruits

...

Descargar como (para miembros actualizados)  txt (31.4 Kb)  
Leer 19 páginas más »
Disponible sólo en Clubensayos.com