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Different parts of different plants can be used as fruits or vegetables for human consumption. You can roots, tubers, bulbs, stems and shoots, flowers, leaves and fruits or pods and seeds. It is important to learn about the plants and cell and compounds for taste, texture and color in order to obtain reliable information on the effects of various treatments on these quality characteristics. Structure of plants: Cells Cell components are divided into two categories; protoplasmic and non-protoplasmic. The protoplasm is the living active section of the cell, and it contains specific components. The core and controls the metabolic activity of the cell. The cytoplasm is an undifferentiated part of the plasma around the nucleus and the creation of a relatively thin layer in the cell wall. The plasma membrane (plasmalemma) is a thin membrane on the outer surface of the cytoplasm. The plasmatic membranes are permeable and can help distribute the separation and transport of metabolites and thus the enzymes to regularly. There are a few places are arranged in the cytoplasm called plastids, which are divided into three groups; leucoplasts, chloroplasts and chromoplasts. Leucoplasts are poor in pigmentation and are storing food are related. Many of them produce store and strength. The chloroplasts contain chlorophyll in green plants. Chromoplasts contain xanthophylls and carotenes, which usually orange or yellow color. They appear in some vegetables like carrots and sweet potatoes. The non-protoplasmic components of the cell include cavities called vacuoles involving cell sap. The sap is an aqueous material with a number of substances such as sugar, salts, organic acids, polysaccharides, phenolic, flavones, and the red or blue pigments (anthocyanins). The substances in the cell sap are nutrients through the cytoplasm or metabolic consumption. The liquid in the vacuole of the cell is responsible in relation to the texture of fruit and vegetables. Cell wall components of the cell by a wall, which is responsible for covering the texture of the fabric. Cells are attached by intercellular layer or middle lamella. This layer is that there is a cementing function of pectin in one or more of its forms. In immature cells, the outer (primary) is created first wall. Soft tissue that occur in some fruits contain only the primary walls. The primary wall consists of cellulose, hemicellulose, and some pectin. is produced in some tissues secondary wall in the primary wall. Properties of plant cell walls: cellulose occurs – and is highly important in relation to the strength of the cell wall. Cellulose is polysaccharide of glucose units. Hemicelluloses – not highly similar to cellulose. They are insoluble in water and soluble in alkali. They can easily be hydrolyzed by alkali, which can result in the mushiness vegetables after heat treatment in water with baking soda. The amount of hemicellulose in vegetables decreased by boiling. Hemicelluloses are polysaccharides in which xylans, galactans, mannans can be found glucomannan. The hemicelluloses in apples, tomatoes, pears and citrus fruits have xylose. The cell walls of many fruits contain mannans. Lignin – this is also a major component of some cell walls. It is largely in wood. Some vegetables, which are mature and practical firm also contain lignin. Lignin molecules are polymers of phenylpropene derivatives. Gums – is another component of cell wall carbohydrates. The gums may arise as a result of the presence of microorganisms or by the occurrence of disease or mechanical damage to the cell. The gums may consist of a mixture of several sugars or sugar derivatives. You can swell many times their original volume in water. Pectic – apples and the albedo of citrus fruits that large amounts of pectin-containing material. The pectic pectic acid are, pectinic acids, pectin and protopectin. Changes during cooking and processing: heat treatment of fruit and vegetables is an important method of preservation. If the pectin in cell walls break down, softening can be done to the wall cells and then separated. Divalent ions may increase resistance of canned fruit, canned tomatoes and boiled carrots. The divalent ions cross-link forms between the carboxyl groups of pectinic acid molecules, the stability of the middle lamella and primary cell wall is increased. But if monovalent ions are present, the cross-link formation is stopped and thus stiffness is reduced. When plant tissue is heated, intracellular ions such as calcium and magnesium may come into contact and react with cell wall components, eg free carboxyl groups to create bridges and strengthen the fabric so that it withstand a loss of quality when heated. Another essential aspect in loss of strength during the heating process is the pH f, the heating medium. E. g. when the pH increased 3-8, decreases the stiffness of carrots, as the cell separation has increased. The heating effect varies with the type of tissue such as phloem and xylem. Color Color is perhaps the most important factor influencing the attractiveness of the fruit and vegetables. There are many studies to identify and obtain the optimal techniques to the adverse effects on the quality of fruits and vegetables have been minimized, including color. Chlorophyll – the green pigment of plants what is involved in the chloroplasts. Chlorophyll in the leaves acting as their large surface area is suitable for the absorption of solar radiation and the exchange of gases for photosythesis. Chlorophyll is soluble in fat and solvents such as diethyl ether, ethanol, acetone, chloroform, carbon disulfide and benzene. All higher plants and many lower plants have two types of chlorophyll (a) and (b), in a ratio of about 3 parts of chlorophyll (a) to 1 part of chlorophyll (b). Chlorophyll (a) is blue-green in color, chlorophyll b () is yellow-green. Changes during the warming: The changes that may occur in pigments from green vegetables are associated with the properties of chlorophyll. Chlorophyll of raw vegetables can be protected from acid in the cell by SAP’s position in the chloroplasts. The original color can change identified when the green vegetables in boiling water in lightening the color green, which may as a result of the expulsion of air and collapse of the intercellular spaces are kept, to be dropped. During cooking, the choloroplasts shrink and get in the middle of the coagulated protoplasm clumped. no longer protected at this stage, the remaining chlorophyll in the chloroplast through the plastid membranes from the acidic cell sap. As a result, the dull olive green pheophytin be formed. The degree of color change depends on the acidity of the cooking medium, the pH of the plant, the chlorophyll content and the duration and temperature of cooking. The pH value of all common vegetables is less than 7 because of the acids, which are in the cell sap. Both volatile and nonvatile acids are discharged when cooking vegetables. Acids released from the cell vacuole when heated not in a position to influence the color of the vegetables when they are neutralized by the cooking water. The pH of the water can be reduced by boiling, if carbon dioxide is released (dissolved in water to produce carbonic acid), or bicarbonates to carbonates with the release of carbon dioxide, hydrogen sulfide or when converted lost. The amount of acid, which can be neutralized by an alkaline cooking water depends directly on the water alkalinity and volume. may be highly desirable from a green water color because they neutralize or at least dilute acids plant. Baking soda can be added to the cooking water to increase alkalinity, but this is not recommended because of the possibility of excessive addition of soda. Sodium bicarbonate is not neutralized by the acid in the cooking water can have an adverse effect on the taste and texture of the vegetables. reduce acid in blanching and the pH value of vegetables is increased. alter the sensitivity of green vegetables during cooking color is affected by their content of chlorophyll and its pH. Frozen vegetables contain more chlorophyll than they initially receive a share when cooked. In addition, vegetables with a high pH, spinach and peas retain more pigment than green beans and Brussels sprouts, have the lower pH. If green vegetables as quickly as possible, the color would not / heated change slightly. Canning process has resulted in a significant effect of color changes in green vegetables from the conversion of chlorophyll to pheophtin. Carotenoids, the yellow and orange color and some of the red color of fruits and vegetables are carotenoids, which are in chromoplasts of cells causes. The carotenoids are insoluble in water, but soluble in fats and organic solvents. They are divided into two groups. Carotenes contain only hydrogen and carbon, and are soluble in petroleum ether. Xanthophylls, oxygenated carotenoids are soluble in alcohol. Conclusion In principle, the amount of color and texture change, depends on the acidity of the cooking medium, the pH of the plant, the chlorophyll content and the duration and temperature of cooking. Pectins in the form of vegetables, water gels, to give the maintenance of their structure to help vegetable. Pectins are soluble in the boiling water to make the cooked vegetable extracts mushy. can form calcium ion Ca2 + in hard water link between pectin molecules makes them less soluble and keeps the vegetables tough. The calcium ion content of water can change the color of the cooked vegetables and their texture, but indirectly through its effect on pectin molecules. Since most vegetables require a degree of softening due to heat treatment, ie cooking in hard water, that more needed to be to achieve the optimal softening. During this longer cooking time more chlorophyll is converted phenophytin and the color of green vegetables will brown. To reduce this effect to an ideal consistency and pleasant colors of vegetables (cooked and as short as possible to achieve), water should contain low Ca2 +.