Homogenization foodstuffs

Both steel and copper vessels may be lined with thin silver sheets in the same way as for homogeneous lead lining. As silver is extremely resistant to most organic acids at all concentrations and temperatures, it is used widely for handling foodstuffs and pharmaceutical products where nontoxicity and... 

For the most part, bulk materials are non-homogeneous, e.g. minerals, sediments, and foodstuffs. They may contain particles of different composition which are not uniformly distributed within the material. In this case, a number... 

Emulsifier not normally used as characteristic ingredients of food Substance which makes it possible to form or maintain a homogenous mixture of two or more immiscible phases such as oil and water in a foodstuff... 

Stabilizers Substance which makes it possible to maintain the physicochemical state of a foodstuff stabilizers include substances which enable maintenance of a homogenous dispersion of two or more immiscible substances in a foodstuff and include also substances which stabilize, retain or intensity an existing colour of a foodstuff... 

Much of the early work which would lead to the identification of proteins as defined chemical entities started from observations on enzymes, either those involved in fermentation or on the characterization of components in gastric secretions which powerfully catalyzed the hydrolysis of different foodstuffs. As well as the digestive enzymes, a number of relatively pure proteins could be isolated from natural sources where they made up the major component (Table 1). Because of the importance and difficulty of isolating pure proteins and demonstrating their homogeneity, functionally active and relatively abundant... 

Supercritical CO2 at temperatures of 31-50 °C and pressures of about 10 MPa is now widely used as a nontoxic extractant of excess fats from foodstuffs and in decaffeinating coffee, but its largest scale future use is likely to be the enhancement of recovery of oil that cannot be extracted from wells by conventional techniques. Supercritical CO2 is finding increasing favor as a solvent for chemical syntheses, for example, in the radical-promoted polymerization of fluoroacrylic monomers in homogeneous solution, for which ozone layer-destroying chlorofluorocarbons had been the only effective solvents previously.210... 

The Extrelut cleanup method is suitable for most foodstuffs, such as cheese, yogurt, and other samples that tend to form emulsions during extraction. The prepacked or refilled Extrelut column in a plastic tube consists of a wide-pore kieselgel column. A sample is homogenized in 0.5 N sulfuric acid, diluted with water, and applied onto the Extrelut column for at least 15 min. The absorbed preservatives are eluted with a chloroform - isopropanol (9 1) mixture, and the elu-ate is collected and evaporated carefully nearly to dryness. The last few milliliters of solvent are removed with a gentle flow of nitrogen to prevent substantial losses of BA and SA, which have relatively high vapor pressures. The residue is transferred with methanol into a 10-ml volumetric flask and diluted to volume with methanol. To speed up the dissolution, the use of an ultrasonic bath is recommended. The filtered extract is analyzed on a /zBondaPak Cl8 column, with a... 

This method is applicable to a wide range of tissues and should give recoveries 0.5-1.0 ng of a-, / - and y-tocopherols better than 95% overall greater sensitivity can be achieved by the use of an electrochemical detector. For measurement of tocopherols in foodstuffs it may be necessary to adapt the extraction procedure somewhat, and care must be taken to ensure the homogeneity of the sample. 

Method. If the sample is a solid or a semi-solid, homogenise it witii an equal quantity of water. In the case of foodstuff s or stomach contents, treat the homogenate with saturated calcium chloride solution, allow to stand overnight, and filter. Extract SOI aliquot of the s nple or of the filtered homogenate with SOI equal voliune of redistilled ether, separate, and retain the ether fraction. Adjust the aqueous fraction to pH 2 by the addition of 2M hydrochloric acid, extract with an equal volume of ether, and combine the two ether fractions. Retain the aqueous fraction for later examination. 

The presence of PAA may serve as fingerprints for detection of other functional groups. Unreacted isocyanates used in manufacture of corks may migrate to foodstuffs and hydrolyze there to the corresponding PAA. Thus, cork homogenates in water were extracted with hexane and analyzed by GC-MS for the presence of diamines such as 2,4-diaminotoluene (2e), 2,6-diaminotoluene (2f) and 4,4 -methylenedianiline (5a)65. A combination of pyrolysis with GC-MS was applied to qualitative analysis of azo dyes by detection of aromatic amines in the pyrolysate. This fast detection method was applied in... 

In the case of foodstuffs of animal origin, sampling from milk and milk products is covered by a number of ISO standards - 707 1997 5538 1987 8197 1988. The purpose of these defined procedures is to ensure representativeness of the sample for a variety of nonhomogeneous and homogeneous solid and liquid, bulk and packaged foods. For meat and edible tissues, samples taken from liver or kidney are usually representative, although there may be differences in residue content between the two sections of the kidney (medulla and cortex). Samples from carcasses are normally taken from the same position (muscle or fat) on each carcass and chosen so as to reduce commercial loss as much as is possible. 

---