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Book Review Handbuch der Lebensmittelchemie (Manual of Food Chemistry). By J. Schormller

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BOOK REVIEWS
Handbuch der Lebensmittelchemie (Manual of Food Chemistry). By J. Schormiiller. Vol. 11, Part 1: Analytik der
Lebensmittel. Physikalische und physikalisch-chemische
Untersuchungsmethoden (Analysis of foodstuffs. Physical
and physico-chemical methods of investigation). Springer
Verlag, Berlin-Heidelberg-New York 1965. 2nd ed., xxiv,
944 pp.,DM 236.Physical and physico-chemical methods are of great value in
the investigation of foodstuffs. Very far-reaching changes in
methods have taken place since the publication of the first
edition of the manual. Consequently, the first volume[*],
which is devoted to the components of foodstuffs, is followed
by a second volume on the analysis of foodstuffs. The 31
chapters follow the same scheme. The book starts with a
theoretical introduction to the field, and this is followed by a
description of the apparatus and its use, and notes on special
problems of food chemistry.
H. Werner first describes sampling and associated questions
(13 pp.). The descriptions are assisted by a number of good
schematic drawings. The physical concept of density and its
determination in liquids, solids, and gases is described by
A . Mahling (26 pp.). The term “specific gravity” is avoided
because of the confusion of the terms. The same author
contributes articles on viscosity (20 pp.) and the ultracentrifuge (24 pp.). Theoretical explanations are skilfully linked
with practical instructions in these articles. The same is true
of the two chapters by H . Wollenberg, ‘Ultracentrifugation,
Dialysis, and Electrodialysis” (26 pp.) and “Phenomena at
Phase Boundaries” (32 pp.). Theoretical explanations of the
melting point, solidification point, and boiling point, and a
description of the apparatus used for their determination are
contributed by H . J . Henning (33 pp . Some mention of zone
melting, which has proved an.excellent method for the
purification of substances would have been desirable here.
In his discussion of solubility (23 pp. H . J . Henning discusses
open questions as well as known facts. K . Vo/z contributes a
short paper on calorimetry ( 5 pp.). In line with the frequent
use of pH measurements, these and all related questions are
discussed at length by D . Berndt (34 pp.). Mention is also
made of older methods that are less common in food chemistry. The redox potential is discussed in general and from
the point of view of biology and food chemistry by W . Heimann and K . Wisser (40 pp.). The chapter is supplemented by
seven tables. K. E. Slevogt discusses conductometry and dielectrometry (37 pp.).
ln the reviewer’s opinion, K. Pfeilsticker’s chapter (42 pp.)
on emission spectral analysis passes beyond the scope of
food analysis in places. The principles, technique, and value
of flame photometry in the analysis of foodstuffs are described by w . Diemair and K. Pfeilsticker. Light-absorption
measurements in the visible and ultraviolet regions and
infrared spectra (47 pp.), color measurements (7 pp.), and
luminescence analysis (20 pp.) are explained well by J. Eisenbrand. The reader is introduced to optical polarimetry,
poIarization, and (briefly) rotatory dispersion by J . F&ge
(40 pp.). Interferometry is mentioned by J. Eisenbrand ( 5 pp.).
The important topic of polarography is discussed by W . Diemair and K . Pfeilsticker (18 pp.). A good survey of the
history and techniques of paper chromatography is contributed by A . Griine (45 pp.), who also refers briefly to labeling
with radioactive isotopes. In connection with G . Wohlleben’s
chapter on column chromatography (9 pp.), special mention
should be made of the discussion of the suitability of various
inorganic and organic adsorbents. Ion exchangers and molecular sieves are also briefly described. Thin-layer chromatographic analysis (24 pp.) is discussed by A . Seher, starting
with a short introduction and proceeding to consider various
groups of substances that are of interest in food chemistry.
Corresponding to the great importance of gas chromatoAngew. Chem. internat. Edit. 1 Vol. 6 (1967) 1 No. 2
graphy, F. Drawerf (69 pp.) not only discusses in detail the
theory and the structure of individual instruments and parts
of instruments, but also presents many items of general
interest. The chapter is supplemented by a large number of
examples of applications. Electrophoresis (20 pp.) is discussed by H . D . Behlitz, who describes, not only methods,
but also applications to various classes of substances. The
authority on multiplicative distribution, E. Hecker, presents
a concise survey of this special field (31 pp.). The increasingly
important task of detecting radionuclides in foodstuffs is
discussed by K. G. Bergner and P . Jagerhuber (38 pp.). The
topics covered include sampling, methods of measurement,
and evaluation of the measurements. The authors finally
offer suggestions for the equipment of a laboratory. Under
the heading “Microscopy”, H . Freund (41 pp.) discusses
microscopes, (including the electron microscope), accessories,
and techniques. The microscope specimens and the staining
of bacteria specimens is described by F. Walter (37 pp.). The
calibration of measuring instruments is surveyed by H . Johannsen (19 pp.). H . Ramb presents an introduction to the
fundamentals of refractometry, technical refractometry, and
the application of this method to special foodstuffs (34 pp.).
In the last chapter, K. Feiling discusses nephelometry (7 pp.).
The subject index covers 29 pages.
Each chapter is accompanied by an extensive bibliography,
and in almost every case by a comprehensive list of journal
references. The literature is covered up to 1964. The present
volume is a valuable aid to anyone who is concerned with
food chemistry and who wishes to use the latest methods in
his work.
C. H . Brieskorn
[NB 534 IE]
[ * ] Cf. Angew. Chem. 78, 398 (1966); Angew. Chem. internat.
Edit. 5 , 431 (1966).
HMO - Hiickel Molecular Orbitals. By E. Hcilbronner and
P . A . Straub. Springer-Verlag, Berlin-Heidelberg-New
York 1966. 1st ed., 816 pp., loose leaf DM 72.-.
It is becoming an increasingly established practice, in seeking
for an understanding of the properties of molecules and in
discussing possible reaction mechanisms, to turn to the results
of Huckel molecular orbital (HMO) calculations rather
than to write out resonance structures, as was formerly
common. A systematic application of the HMO method in
chemical practice seems possible only if there is no need to
carry out a HMO calculation in each individual case and one
may simply look up its results. The present set of tables,
with a short but clear introduction on their use, is therefore
very welcome.
It is not very important to the experimental chemist to
understand the conditions and limitations under which the
HMO theory can be derived from quantum mechanics. It is
more important that he should be able to use the results of
HMO calculations, and to draw chemically relevant conclusions from molecular diagrams, from the scheme of the
orbital energies, and possibly also from the polarizabilities
and other numerical values. This requires not only study of a
textbook of MO theory, but also a certain amount of experience, and this experience can probably be built up more
rapidly with the aid of the present tables.
It should be noted tha the HMO method aDplies only to the
n-electron systems of unsaturated compounds, so that it
cannot be expected to provide answers to questions specifically concerned with cs bonds. The number of possible xelectron systems is so great that it would be futile to hope for
completeness. However, about 800 systems are tabulated in
the book, starting with simple chains and rings, and progressing to very complex combinations of rings of various
sizes and branched chains. It includes the most important
189
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