Water protein foods, from

In agricultural applications, the most commonly analyzed constituents are water, protein, starch, sugars, and fiber [16-20]. Such physical or chemical functions such as hardness of wheat, minerals, and food values have no actual relation to chemicals seen in the NIR. These are usually done by inferential spectroscopy. That is, the effect of minerals or the relationship of the spectra to in vitro reactions is used in lieu of chemical analyses to NIR active constituents. Considering that all shipments of grain from the US since the 1980s have been cleared by NIR, it can be argued that this is a critical application of the technique. 

In contrast to its MIR counterpart, an important application of NIRS is the routine quantitative determination of species, such as water, proteins, hydrocarbons, and fats, for example, in food or feed products, but also in the petroleum and chemical industries. Figure 13 illustrates a collection of spectra from a pharmaceutical product with varying water content. It shows that a quantitative application can be... 

Dickinson, E., Tanai, S. (1992). Protein displacement from the emulsion droplet surface by oil-soluble and water-soluble surfactants. Journal of Agricultural and Food Chemistry, 40, 179-183. 

Zein is a vegetable protein obtained from corn gluten meal. Pure zein powder is odourless, tasteless, hard and water-insoluble. Since it is edible, it finds applications in processed foods and pharmaceuticals, in competition with chitosan and chitin. 

The strong hydrochloric acid, naturally present in the stomach, hydrolyses (adding on the elements of water) the foods containing proteins to form small amino acids for transport by the blood into cells. These small amino acid units are the starter building blocks for specific sequences of amino acids needed inside the cells for protein building. The proteins manufactured in the cells are different from those taken in as food, which is why they first have to be broken down into small units for eventual remaking and rearranging into those specifically required by the cells. 

Peng, Z., Pocock, K.F., Waters, E.J., Francis, I.L., WiUiams, R.J. (1997). Taste properties of grape (Vitis vinifera) pathogenesis-related proteins isolated from wine. J. Agric. Food Chem., 45, 4639-4643... 

Severe protein-energy malnutrition often occurs after weaning, the transition frcim nursing to the consumption of foods from other sources (i.e.. Solid foods). The marasmus common in Latin America is caused by early weaning, followed by use of overdiluted commercial milk formulas. Kwashiorkor occurs in Africa, where babies arc fed starchy roots, such as cassava, that arc low in protein. It also occurs in the Caribbean, where babies are fed sugar cane. The major symptom of kwashiorkor is edema, mainly of the feet and legs. Edema is the condition produced when water normally held in the bloodstream by osmotic pressure leaks into (jther extracellular spaces. It can result from reduced osmotic pressure in the bloodstream caused by catabolism and depletion of serum albumin. 

A semipurified diet based on textured soy protein purchased from General Mills Co., Minneapolis, Minn. (Bontrae Products) and Worthington Foods Co., Division of Miles Laboratory, Elkart, Indiana, was developed for this study. Soy protein isolate, which was used as soy flour in the baked goods, was purchased from General Biochemicals (Teklad Mills, Chagrin Falls, Ohio). The texturized soy meals used were hamburger granules, chicken slices, turkey slices, and chicken chunks. The texturized soy protein and soy protein isolate were washed twice with ethylenediaminetetraacetate (EDTA), then rinsed three times with deionized water, boiled for 30 minutes, and kept frozen until ready to be... 

Fig. 1.6 Respiration. Energy is obtained by converting foodstuffs (organic material composed mainly of carbohydrate, fat, and protein) to oxygen and water. These organisms obtain the food from many sources and are called heterotrophs...

There are and have been available for some time a number of well-known texts which consider the chemistry of foods—their chemical character as carbohydrates, proteins, lipides, vitamins, vitagens, mineral matters, coloring matters, and related categories. In some of these the stress is on the nutritional aspects, as in Sherman s Chemistry of Food and Nutrition and Food Products Bailey s Food Products from Afar and Olsen s Pure Foods Their Adulteration, Nutritive Value, and Costs. One of the earliest of such texts was that of Richards and Woodman, Air, Water, and Food (1900), which stressed sanitary aspects. Possibly the first book to tie chemistry directly to food industries was Chemistry and Technology of Food and Food Products edited by Jacobs in 1944. 

Solutes are one of the major components of foods, and they have significant effects on their adsorption at fluid interfaces. In addition, the study of the effects of ethanol and/or sucrose on protein adsorption at fluid interfaces is of practical importance in the manufacture of food dispersions. The presence of ethanol in the bulk phase apparently introduces an energy barrier for the protein diffusion towards the interface. This could be attributable to competition with previously adsorbed ethanol molecules for the penetration of the protein into the interface. However, if ethanol causes denaturation and/or aggregation of the protein in the bulk phase, the diffusion of the protein towards the interface could be diminished. The causes of the higher rate of protein diffusion from aqueous solutions of sucrose, in comparison with that observed for water, must be different in aqueous ethanol solutions. Since protein molecules are preferentially hydrated in the presence of sucrose, it is possible that sucrose limits protein unfolding in the bulk phase and reduces protein-protein interactions in the bulk phase and at the interface. Both of these phenomena may increase the rate of protein diffusion towards the interface. Clearly, the kinetics of adsorption of proteins at interfaces are highly complex, especially in the presence of typical food solutes such as ethanol and sucrose in the aqueous phase. 

Gunning, P.A., Mackie, A.R., Gunning, A.R, Wilde, P.J., Woodward, N.C., and Morris, V.J. The effect of surfactant t)rpe on protein displacement from the air-water interface. Food Hydrocolloids, 18, 509, 2004b. 

Applications of immunoassay to pesticide chemistry have been described which address some difficult problems in analysis by classical methods. These include stereospecific analysis of optically active compounds such as pyrethroids (38), analysis of protein toxins from Bacillus thuringiensis (5,37), and compounds difficult to analyze by existing methods, such as diflubenzuron (35) and maleic hydrazide (15 also Harrison, R.O. Brimfield, A.A. Hunter, K.W.,Jr. Nelson, J.O. J. Agric. Food Chem. submitted). An example of the excellent specificity possible is seen in assays for parathion (10) and its active form paraoxon (3). Some immunoassays can be used directly for analysis without extensive sample extraction or cleanup, dramatically reducing the work needed in typical residue analysis. An example of this is given in Figures 2 and 3, comparing the direct ELISA analysis of molinate in rice paddy water to the extraction required before GC analysis. 

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