Some are actually fruit; others are buds, leaves, stems, roots or storage organs. Where the vegetable comes from on the plant affects how well it stores and many of its sensory qualities. The origin of vegetables affects how they are best handled after harvest. For example, vegetables from above the ground are more likely to have waxy skins to protect them from water loss. Roots and tubers do not have such protection, so may require high humidity to limit dehydration.
Seeds necessarily contain stored energy in the form of sugars or carbohydrates. Buds and shoots generally have few stored reserves and are developing rapidly, so need careful handling to preserve them after harvest. That is, fruits are produced by plants in order to be eaten, and will eventually detach by themselves if not actively harvested. Unlike fruit, most vegetables are not adapted to exist apart from the whole plant.
Once harvested, vegetables are cut off from their source of water and nutrients. Without sunlight, they are unable to photosynthesise and are usually removed from the protection of soil or foliage. With the exception of vegetables which are mature fruit, bulbs or storage organs pumpkin, onions, sweetpotato, etc. The role of postharvest management is to delay deterioration, maintaining freshness, nutrition, flavour and texture until vegetables reach the end consumer. Like other living things, vegetables are made up of cells.
There are many different types of cells within even a simple vegetable, and each has different functions within the plant. Plant cells have a fairly rigid cell wall, composed mainly of cellulose, lignins and some proteins. Calcium is critical in the formation of cell walls. If calcium is deficient due to low soil levels or growth faster than the rate of transport within the plant the growing tips of fruiting vegetables such as zucchini and eggplants will lack structural integrity and can break down.
This is the cause of blossom end rot. The cell wall is permeable to water and solutes. Inside the cell wall is the plasmalemma, which acts like a liner. The plasmalemma helps maintain pressure inside the cell, keeping it turgid.
It is this turgidity that keeps vegetables firm and crisp. Adjacent cells are glued together by a layer of pectins. A series of channels plasmodesmata allows exchange of various substances between cells. Within the cytoplasm float various structures and organelles, each of which has a specific purpose. If the cell walls are broken—by freezing or physical injury—then the turgidity of the cells is lost and the contents leak out, resulting in soft, water-soaked tissue.
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This is a preview of subscription content, log in to check access. Individual-sport versus team-sport athletes and altitude training. Bhattacharya S, Malleshi NG Physical, chemical and nutritional characteristics of premature-processed and matured green legumes. Rom Biotech Lett 18 2 — Google Scholar. Butnariu M Bioavailability of anti-radical antioxidants activity compounds. J Anal Bioanal Tech 3:e Butnariu M Detection of the polyphenolic components in Ribes nigrum L.
Butnariu M, Caunii A Design management of functional foods for quality of life improvement. Butnariu M, Grozea I Antioxidant antiradical compounds. Vegetables are characterized by high nutritional density with low energy input and contain a variety of biological phytonutrients that make them an important part of the basic diet.
It is recommended that vegetables be consumed fresh when their nutritional value is at its highest; some methods of processing and storage cause some water-soluble vitamins and nutrients to be lost. With energy from the sun, vegetables synthesize the basic compounds necessary for their survival carbohydrates, lipids, and proteins , and a variety of organic phytochemicals can be extracted as raw materials that have important applications in dermatology, cosmetics, medicine, technology, and commerce.
Skip to main content. This service is more advanced with JavaScript available. Advertisement Hide. Chemical Composition of Vegetables and Their Products. Reference work entry. This process is experimental and the keywords may be updated as the learning algorithm improves. This is a preview of subscription content, log in to check access.
Individual-sport versus team-sport athletes and altitude training. Bhattacharya S, Malleshi NG Physical, chemical and nutritional characteristics of premature-processed and matured green legumes. Rom Biotech Lett 18 2 — Google Scholar. Butnariu M Bioavailability of anti-radical antioxidants activity compounds.
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