Solvents foodstuffs

In addition to being the most widely used disinfectant for water treatment, chlorine is extensively used in a variety of products, including paper products, dyestuffs, textiles, petroleum products, pharmaceuticals, antiseptics, insecticides, foodstuffs, solvents, paints, and other consumer products. Most chlorine produced is used in the manufacture of chlorinated compounds for sanitation, pulp bleaching, disinfectants, and textile processing. It is also used in the manufacture of chlorates, chloroform, and carbon tetrachloride and in the extraction of bromine. Among other past uses, chlorine served as a war gas during World War I. 

Cans with replaceable closures for such products as dry foodstuffs, pharmaceuticals, tobacco, solvents, liquid fuels and paint. These usually contain an appreciable amount of oxygen. Tinplate closures for bottles and jars made of non-metallic materials may also be considered in this category. 

Another extension of the DFG S19 method was achieved by applying it successfully to foodstuffs of animal origin such as whole milk and egg, muscle meat, offal, fat and honey. Depending on water and fat content, either water-acetone (e.g. for milk, meat, possibly egg and honey) or acetone-acetonitrile (e.g. for offal, egg, fat) solvent extraction is preferable. When high fat or oil contents in the raw extract are expected,... 

Although the improved extraction kinetics also increase the concentration of coextractives in the final extract, some degree of selectivity can be achieved by careful selection of the solvent or solvents used. Matrix co-extractives may be removed, or at least partially removed, by placing a suitable sorbent, such as alumina, at the exit of the extraction cell to remove lipid co-extractives. Excellent recoveries of both polar and nonpolar pesticides from a wide range of foodstuffs have been reported. Specific applications include organophosphorus and A-methylcarbamate pesticides. 

Multi-residue Method S19 of the DFG Manual,including Cieanup Procedure Xll-6 (gel-chromatographic cleanup), has been used successfully in many laboratories because of its broad applicability for the gas-chromatographic determination of pesticide residues in foodstuffs. DFG method S19 is also included in the respective European Standards. Subsequently, a modification of the extraction and partition step has been implemented. The modified method requires less experimental effort and eliminates the use of dichloromethane, which is an undesirable solvent for toxicological and ecological reasons. As the results from validation studies demonstrate,... 

Volatiles and monomers in insoluble polymers. Aroma volatiles from foodstuffs, fruits, spices, tobacco, etc. Residual solvents in pharmaceuticals and printed films. 

Major types of volatile constituents in polymers include unreacted monomers, nonpolymerisable components of the original charge stock, residual polymerisation solvents, and water. Frequently, complex nonpolymerisable mixtures are present. The concentration of these substances may need to be determined for various reasons, such as the effects on materials properties and the risk of tainting in foodstuff- and beverage-packaging grades. For this purpose various GC methods are in regular use ... 

General properties. The solvent should be nontoxic for applications such as the manufacture of foodstuffs. Even for the manufacture of general chemicals, the solvent should be preferably nontoxic for safety reasons. Safety also dictates that the solvent should preferably be nonflammable. Low viscosity and high freezing point will also be advantageous. 

Producers of board try to manufacture board for foodstuff packaging with other, less mineral oil-contaminated RCP grades. Major sources of mineral oil in paper for recycling are offset coldset inks preferably used in newspapers and which contain typically 20-30% mineral oil as solvent [12]. By appropriate sorting of the RCP, the theoretical possibility exists to remove newspapers from collected household paper mixtures, so-called household collections, so that a mixed RCP grade without newspaper is generated especially for board production. 

The addition of water or the use of an aqueous solvent mixture is important for the extraction of other organic analytes from dry foodstuffs or dehydrated foods. It is particularly necessary in aiding the permeation of solvent through freeze-dried samples. 

Atomic absorption spectrometry is one of the most widely used techniques for the determination of metals at trace levels in solution. Its popularity as compared with that of flame emission is due to its relative freedom from interferences by inter-element effects and its relative insensitivity to variations in flame temperature. Only for the routine determination of alkali and alkaline earth metals, is flame photometry usually preferred. Over sixty elements can be determined in almost any matrix by atomic absorption. Examples include heavy metals in body fluids, polluted waters, foodstuffs, soft drinks and beer, the analysis of metallurgical and geochemical samples and the determination of many metals in soils, crude oils, petroleum products and plastics. Detection limits generally lie in the range 100-0.1 ppb (Table 8.4) but these can be improved by chemical pre-concentration procedures involving solvent extraction or ion exchange. 

P.B.24 x, a greenish blue compound, is registered in the USA as FD C Blue 1 for use in foodstuffs, pharmaceuticals, and cosmetics, provided certain purity standards are met. The pigment possesses poor lightfastness. It largely parallels P.B.24 , also in terms of tinctorial strength and stability to organic solvents. 

Heuser SG, Scudmore KA. 1969. Determination of fumigant residues in cereals and other foodstuffs A multidetection scheme for gas chromatography of solvent extract. J Sci Food Agric 20 566-572. 

The Council and the Commission must adopt positive fists of additives, authorised to the exclusion of all others, fists of foods in which the additives may be used with conditions of use, and rules on carrier solvents. The Standing Committee on Foodstuffs must approve adoption of purity criteria for listed additives and, if necessary, methods of analysis to verily these purity criteria, sampling procedures and methods of analysis for food additives in food. The directive includes provisions that a member state may temporarily suspend or restrict application of an authorisation if it has detailed grounds for considering that the use of the additive in food, although permitted, endangers health. The... 

Solvent effects. As any modem cook knows, a microwave oven is a superb means of cooking any foodstuff containing water, when irradiated with microwaves of sufficient frequency, will absorb energy and so the food gets hot and therefore cooks . Unfortunately, microwaves are at the very heart of EPR spectroelec-trochemistry experiments, so care is therefore required to remove all traces of water. 

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