Fruit responsibility

Ethephon has received the most attention for use in loosening fruit as an aid to mechanical harvesting. Various degrees of success have been obtained using ethephon on olives (78, 79, 80), blueberries 81), cherries 82-86), plums (87), peaches (88, 89), and apples (90, 91, 92, 93). The initial visible fruit response is an increase in coloration, but higher concentrations do result in abscission of the fruit. 

As a food chemist, I conduct research on phytochemical compounds in fruits responsible for their color, flavor, and potential health benefits. I know that all fruits inherently contain some level of nutrients, that not all varieties of the same fruits are the same, and that all contain at least some nonnutrient compounds known as phytochemicals that may contribute directly or indirectly to our overall health and wellness. To use a... 

The discovery of pectin, as a chemical compound, was made by Vauquelin in 1790. In 1824, Bracon not was the first to characterize the pectin as a composed of fruit responsible for the gel formation and the same author suggested the name pectin from greek, which means thick. Until 1930, pectin was considered as a small cyclic structure Smolenski in 1923, was the first to suggest that pectin was a complex polymer, similar the starch structure. Later, X-ray analysis indicated it to be more consistent with cellulose (Owens et al., 1946). According to Meyer and Mark (1930), the pectin contains in its structure methyl ester groups attached in the position 1-4 (Baker, 1948) and the basic formula was established by Schneider and Bock, 1937 (Cybercolloids, 2008). In the beginning of the studies with pectin, the difficulty in establishing comparative studies about the composition of pectin due the different method of... 

Polyterpenes. Polyterpenes is one of the first classes of non-polar tack-ifiers to be developed. Terpene monomers are a by-product in the extraction of rosin from wood stumps or tree sap, and from the extraction of oils from citrus fruits. The latter is the dominant source. As such, polyterpene prices generally mirror those of citrus fruits, which fluctuate substantially from one growing season to the next. Terpenes like rosin are cyclic, see Fig. 6, which is partly responsible for their excellent solvent properties. 

An alkene, sometimes caJled an olefin, is a hydrocarbon that contains a carbon-carbon double bond. Alkenes occur abundantly in nature. Ethylene, for instance, is a plant hormone that induces ripening in fruit, and o-pinene is the major component of turpentine. Life itself would be impossible without such alkenes as /3-carotene, a compound that contains 11 double bonds. An orange pigment responsible for the color of carrots, /3-carotene is a valuable dietary source of vitamin A and is thought to offer some protection against certain types of cancer. 

Esters are among the most widespread of all naturally occurring compounds. Many simple esters are pleasant-smelling liquids that are responsible for the fragrant odors of fruits and flowers. For example, methyl butanoate is found in pineapple oil, and isopentyl acetate is a constituent of banana oil. The ester linkage is also present in animal fats and in many biologically important molecules. 

Natural product total syntheses are particularly valuable when they are attended by the development of general utility methods of synthesis. In some instances, the successful completion of a natural product total synthesis requires the development and application of a new synthetic method. The total synthesis of erythronolide B by Corey et al. is one of these instances. The double activation macro-lactonization method was a fruitful innovation that was introduced in response to the challenge presented by the macrocyclic structures of the erythromycins. Several other methods to achieve the same objective, and numerous applications followed. 

Much valuable research has been devoted to developing the basic principles for the production of frozen fruits and vegetables of high and uniform quality. If this knowledge could be applied to its fullest extent, there would be little need for concern over the quality of such foods. Before this can be done, those responsible for quality control must be provided with suitable standards of quality and condition, and objective methods of analysis which will clearly indicate conformance or nonconformance to the standards. Responsibility for this resides with the research food technologist or chemist. It constitutes a rich field for profitable and practical research. 

There is yet much to be done in establishing standards and objective methods in which one may have complete confidence. The frozen fruit and vegetable industry has developed rather rapidly during the past 20 years and it is now time for individuals and organizations responsible for the conduct of frozen food research to concentrate... 

Carboxylic acids with one acid group are known as monobasic acids while those with two acid groups are dibasic acids. All acids with more than one acid group are in the class of polybasic acids. The simplest organic acid, formic acid, is responsible for the irritation of bee and ant stings. Vinegar is a 5% solution of acetic acid in water. The acetic acid is responsible for the characteristic sour taste. Citric acid, found in citrus fruits and used in soft drinks, is a tribasic acid with three carboxylic acid groups. The dibasic acid, adipic acid, is a major component of nylon. 

While TD-DFT continuum calculations for molecules, such as camphor, are not yet quite practicable, efforts to create highly parallel computer codes capable of tackling this scale of problem are expected to be fruitful soon. In the meantime TD-DFT studies for computahonaUy less demanding small molecules [66-68] or highly symmetric molecules, such as SFg [79], have provided indicahons of the general value of the inclusion of electron response effects. 

The carotenoids are the most widespread group of pigments in nature, with an estimated yield of 100 million tonnes per annum. They are present in all photosynthetic organisms and responsible for most of the yellow to red colours of fruits and flowers. The characteristic colours of many birds, insects and marine invertebrates are also due to the presence of carotenoids, which have originated in the diet. Animals are unable to synthesise carotenoids de novo, and so rely upon the diet as the source of these compounds. Carotenoids found in the human diet are primarily derived from crop plants, where the carotenoids are located in roots, leaves, shoots, seeds, fruit and flowers. To a lesser extent, carotenoids are also ingested from eggs, poultry and fish. Commercially, carotenoids are used as food colourants and in nutritional supplements (Table 13.1). Over recent years there has been considerable... 

A further consideration in the choice of gene relates to those that are members of a gene family. Only one member of such a family may be involved in carotenogenesis in a particular tissue. A good example of this is Psy-1 and-2 of tomato. PSY-1 is responsible for phytoene synthesis in ripening fruit (Fraser et al, 1999) whereas PSY-2 is not functional in chromoplasts, even if the protein is produced. 

Carotenoids are lipid-soluble pigments responsible for many of the brilliant red, orange, and yellow colors in edible fruits (lemons, peaches, apricots, oranges, strawberries, cherries, etc.), vegetables (carrots, tomatoes, etc.), fungi (chanterelles), flow-... 

Law, M.R. and Morris, J.K., By how much does fruit and vegetable consumption reduce the risk of ischaemic heart disease response to commentary, Eur. J. Clin. Nutr, 53, 903, 1999. 

Betalains are water-soluble nitrogen-containing pigments responsible for the red and violet (betacyanins class) and yellow (betaxanthins class) colors found in many flowers, fruits, and occasionally in vegetative tissues of plants of most families of the Caryophyllales order (except the Caryophyllaceae and Molluginaceae families, which have anthocyanins instead)." ... 

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