Physical and Physico-Chemical

Milk is a white or yellow-white, opaque liquid. The color is influenced by scattering and absorp- 

Proteins of various sizes are dispersed in milk serum. They are called micelles and consist mostly of calcium salts of casein molecules. Furthermore, milk contains lipoprotein particles, also called milk microsomes, which consist of the residues of cell membranes, microviUi, etc., as well as somatic cells, which are mainly leucocytes (10 /I of milk). Some of the properties of the main structural elements of milk are listed in Table 10.4. 

Various proteins, carbohydrates, minerals and other ingredients are solubilized in milk serum. The specific density of milk decreases with increasing fat content, and increases with increasing amounts of protein, milk sugar and salts. The specific density of cow s milk ranges from 1.029 to 1.039 (15 °C). Defatted (skim) milk has a higher specific density than whole milk. From the relationships given by Fleischmann  

Belitz W. Grosch P. Schieberle, Food Chemistry Springer 2009 

Continent Cow milk Buffalo milk Sheep milk Goat milk 

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Separation processes, as could be seen from Figure 2.1, position themselves at the back end of the sequence in operations in the mineral processing flowsheet. The front-end operations has been found virtually to terminate with the liberation or the size-reduction processes involving crushing and grinding. It is important to limit the amount of size reduction to that at which adequate liberation is accomplished. The term adequacy is related to the cost involved in comminution and to performance of the concentration methods that follows. The concentration is obtained by separation processes which rely on differences in the properties of the particles, the physical and physico-chemical characteristics of minerals. In this context, it will only be relevant to refer to Table 2.5 which presents a summary of the processes along with the properties of the minerals that are exploited. 

Physical and physico-chemical properties Comminuted size, diameter (d), mm Separation process employed... 

All measuring units are indicated by roman symbols. Except for greek letters, physical and physico-chemical properties are, although in the figures represented by roman symbols, in the text and the equations consistently indicated by italic symbols in accordance with the following list. 

The physical and physico-chemical characteristics (e.g., hexagonal 2D surface structure, tetrahedral 3D molecular network) influence the mutual (in)solubili1y significantly chaotropic compounds lower the order by H-bond breaking... 

The most studied non-stoichiometric system in actinide CaF2-structured compounds is the An-0 system all actinide dioxides (with the exception of Th02) present large departures from stoichiometry. Since uranium and plutonium dioxides (and their solid solutions) are employed as fuels in nuclear reactors, a very large effort has been dedicated to the study of their physical and physico-chemical properties. All these properties are affected by the oxygen composition of the compound. 

The chemical, physical and physico-chemical properties of explosives Me dealt with, Mid processes of manufacture are described whenever the substMice in question is of practical importance. 

Two important aspects need to be considered in formulating physical and physico-chemical relationships between properties of molecules and consumer-relevant properties. First, there is a factor of billion difference in length scale between molecular scale and macroscopic scale (nanometers to meters). Second, foods are usually not homogeneous on a length scale of microns, since they exhibit micro-structural units. Examples are bread, beer foam and margarine. 

Sucrose consists of two monosaccharides, glucose and fructose, joined by a glycosidic bond between carbon atom 1 of the glucose unit and carbon atom 2 of the fructose unit (O Fig. 3). Since it contains no free anomeric carbon atom (O Fig. i), it is a non-reducing sugar. Some basic chemical, physical, and physico-chemical properties of pure sucrose are listed in O Table 3. 

Theoretical descriptors derived from physical and physico-chemical theories show some natural overlap with experimental measurements. Several quantum-chemical descriptors, surface areas and -> volume descriptors are examples of such descriptors also having an experimental counterpart. 

The previously described manufacturing processes for flavour chemicals and flavour extracts primarily regard the physical and physico-chemical isolation and purification of naturally occurring flavour chemicals derived from plant and animal tissue. The huge area of organic chemical synthesis of nature-identical and synthetical flavour chemicals is not within the scope of this book. 

Finally, let us summarize the type of binding of volatile flavouring substances to various carbohydrates - as far as it is known (Table 5.1). In essence, this is a matter of reversible physical and physico-chemical binding (adsorption, inclusion complexes, hydrogen bridges), so that, in principle, flavour release takes place in the oral cavity. 

It was the aim of the present paper to show that crystallization in incompatible polymer blends can exhibit a lot of peculiar effects beside the classical well known physical and physico-chemical phenomena. The effects considered here, in particular, are due to the dispersion structure of such blends, and to the changes in the crystallization nucleation conditions which are such caused. They are important from a physical, a material scientific, and a technological point of view as well. 

Because of the technological importance of the perfluorinated ionomers, as well as the novel structural features encountered in these materials, a wide range of physical and physico-chemical tools have been brought to bear on the problems related to the structure of these polymers. 

Automation In data acquisition and treatment can be aimed at a variety of objectives inherent in the above-mentioned factors. It should be pointed out that physical and physico-chemical kinetic factors play a decisive role in the reduction of human Intervention. The acquisition of data at a high rate imposed by the technique Itself (e.g. picosecond spectroscopy [19]) or by the system Investigated (e.g. meaurements of rates of reactions with half-lives of the order of a few milliseconds by the stopped-flow methodology [20,21]) demand the use of a computerized system without which application of the particular spectroscopic technique or method would not be feasible. On the other hand, the so-called microprocessor-controlled spectroscopy , widely commercialized at present, broadens the scope and facilitates the operator s work by eliminating various sources of error. 

Arthropoda include a great portion of the soil animals. The most important are mites, spring-tails, spiders and other groups of insects. They enrich the soil with organic matter to different degrees, and they help to humify it, contribute to mixing of soil and thus to the improvement of its physical and physico-chemical properties. 

Stabilizing Wine by Physical and Physico-chemical Processes... 

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