Mineral food processing

Commonly used solvents inclnde liqnid carbon dioxide, propane, bntane, light oil, triethy-lamine, acetone, methanol, hexane, dimethyl ether, cmde oil, benzene, isopropyl ether, toluene, tricresyl phosphate, methyl isobutyl ketone, methyl chloride, and bntyl acetate. In addition to remediation uses, solvent extraction has been applied in a variety of indnstries, including food processing, pharmaceuticals, fine chemicals, and mining and minerals processing. 

Sodium occurs extensively in feldspars, clay minerals, etc., but is extracted as NaCl from the oceans, in which Na+ is the most abundant cation (10,500 mg kg-1 or parts per million, ppm), and from rock salt deposits. The compounds NaCl, NaHCC>3, Na2C03, Na2S04, and NaOH are used in food processing, road deicing, water treatment, glass manufacture, paper making, and the chemical industry. 

Bioavailability can be influenced directly or indirectly by many physiological, pathological, chemical, nutritional, and processing conditions. Discussion in this chapter will be limited to unit food processing effects upon the bioavailability of nutrients from plant protein foods. The bioavailability of amino acids, carbohydrates, lipids, vitamins and minerals from processed foods will be selectively reviewed. Amino Acids... 

Recent review articles (, 104-109) have described general factors that affect mineral utilization from foods. General factors such as the digestibility of the food that supplies the mineral, chemical form of the element, dietary levels of other nutrients, presence of mineral chelators, particle size of the food or supplemented minerals and food processing conditions all play a role in the ultimate mineral bioavailability (104). Many unit food processing operations can be shown to directly or indirectly alter the level or chemical form of minerals or the association of minerals with other food components. 

Little agreement has been reached as to which dietary components or which food processes physiologially affect mineral availability. Many plant foods contain phytic acid, oxalic acid or other dietary fiber components that can be shown to chelate minerals. The effect of these dietary substances upon the final bioavailability of the mineral in question will depend upon the digestibility of the chelate (106). 

Prunes -food processing of pOOD PROCESSING] Pol 11) -mineral nutrient source [MINERAL NUTRIENTS] Pol 16) -sorbatesm [SORBIC ACID] Pol 22)... 

Inicimn in particular, are readily converted into a nondigesltble or slowly digestible physical form ander certain food processing conditions. These resistant starches are readily fermented by colonic bacteria. Small amounts of waxes, cutin. and minerals in fruits and vegetables contribute to total dietary fiber values but may be physiologically inert. 

B. Evans, Assistant Chemist. Rare-Earth Information Center. Energy itnd Mineral Resources Research Institute. Iowa Slate University. Ames. I,A. http //www.cxternal.ameslab.gov/. Cerium Dysprosium Erbium Europium Gadolinium Holmium Lanthanum Lutetium Neodymium Rare-Earth Elements and Metals Praseodymium Samarium Scandium Terbium Thulium Ytterbium and Yttrium Daniel F. Farkas, Oregon State University. Corvallis. OR. http // oregonstate.edu/. Food Processing... 

There has also been a range of developments leading to the removal of acidity, colour and minerals from clear juices such as apple. The product of such a combination of processes can be a clear, colourless carbohydrate syrup that can be used in a variety of food processes. There seems little doubt that the legal status of such a product is not fruit juice yet it is often, optimistically, so called. 

Mining Processing Minerals Food Production Electronics Components Construction Equipment Financial Services... 

Land disturbance and exposure of buried geologic strata to the open environment leads to sulfide oxidation (if present) and, as a consequence, water-quality degradation of runoff. For water-quality-control purposes, sedimentation ponds required by law are used as water treatment basins. Often, the pH of such basin waters is below 6, and the concentration of heavy metals is above acceptable levels. Water treatments include neutralization and removal of heavy metals as precipitates. Similar water-quality problems arise from other industrial sources, including heavy steel industries, electronics, food processing, mineral processing, and waste-disposal leachates. This portion of the chapter deals with some of the chemical agents used for neutralization purposes and some of their limitations. 

Often overlooked in the evaluation of the effects of diet upon mineral availability is the role that food processing plays in the formation of or breaking of ligand-metal complexes. Several individual or unit processing steps are needed to produce a soy concentrate, a bread or a spray-dried egg white. Some or all steps may have a bearing upon final mineral bioavailability. Soy concentrate from company A is not produced in precisely the same manner as from company B. In fact, lot to lot variation for the same product may be quite variable, particularly in mineral content. 

Treatment to remove dissolved mineral matter is more complex. Dissolved bicarbonates of calcium, magnesium, sodium, and potassium cause alkalinity soluble calcium and magnesium salts cause hardness. Alkalinity and hardness may need to be adjusted for some food processing operations. For example, the formation of a head on beer is critically dependent on water hardness. Excessively hard water may cause discoloration and toughening of certain foods. On the other hand, hardness may be required to prevent excessive foaming in clean-up operations. 

Minerals dissolved in the body fluids are responsible for nerve impulses and the contraction of muscles, as well as for water- and acid-base balance. They play an important role in maintaining the respiration, heart rate, and blood pressure in normal limits. Deficiency of minerals in the diet may lead to severe, chronic clinical signs of diseases, frequently reversible after their supplementation in the diet, or following the total parenteral nutrition. Their influence on biochemical reactions in living systems also makes it possible to use them intentionally in many food processes. 

Because minerals are an integral part of many enzymes, they play an important role in food processing, e.g., in alcoholic and lactic fermentation, meat aging, and dairy food production. Many compounds used as food additives or for rheological modification of some foods contain metallic cations in their structure. A number of these compounds function as antimicrobials, sequestrants, antioxidants, flavor enhancers, and buffering agents, and sometimes even as dietary supplements (Table 4.4). 

The main use of mineral oil in medicine has been as a laxative (an alimentary tract lubricant) and in various pharmaceutical preparations such as ointments, and, as such use continues, this quality of oil is finding increasing utilization as a lubricant for food processing machinery and in plastics manufacture. Laxative oils should be free of odor and taste and also be free of hydrocarbons that may react during storage and produce unwanted by-products. These properties are attained by the removal of oxygen-. 

This chapter focuses on the future trends and shape of the chemical industry. Although chemical manufacture is only part of the process industry as a whole, the basic trends also apply to other areas such as minerals, oil, water and food processing. 

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