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short of describing techniques for the statistical fitting of rate expressions in which the velocity is not simply a hyperbolic function of substrate concentration. In such situations, Cleland's method of calculation, given in one of the computer programs, often fails to converge to a result. But a diligent study of the references might well lead the reader on to these more sophisticatedmethods. E J Wood and D G Herries A short introduction reviews the geography of wine-growing, the history of wine-making and the economic significance of the industry. Different varieties of grape and the type of wine associated with them are listed. The problems of vineyard maintenance and grape diseases are discussed. Most of the book is concerned with the technology of wine production. Differenttypes of yeast, their characterization under the microscope, and their different fermentation properties are described, together with the biochemistry of fermentation and of some wine spoilage reactions. The analysis of wine is described in some detail, including chemical analysis of alcohols, sugars, acids, tannins, etc, and the subjective assessment of the total wine by wine-tasting. A referenceis even made to the analysis of bouquet by gas chromatography! Biochemists are nowadays paying greater attention than ever before to biotechnology. Perhaps this oldest biotechnology of all, with its accumulation of centuries-old wisdom, and its more modem scientific analysis, can provide assistance in other areas of industrial fermentation; for instance, in the selection of micro-organisms, orsimply in the design of industrial plant. T A Scott

Fermentation and Enzyme Technology
by Daniel L C Wang, Charles L Cooney, Arnold L Demain, Peter Dunnill, Arthur E Humphrey, and Malcolm D Lilley. pp 374. John Wiley & Sons Ltd, Chichester and New York. 1979. £17.75 This useful book arises from the series of taught courses in this area organized by Massachusetts Institute of Technology over anumber of years. The coverage is extremely wide and the great expertise of the six authors is apparent in their ability to, together, cover the diversity of subjects ranging from pure Microbiology and Biochemistry to Biochemical Engineering. Fourteen chapters deal respectively with microbial metabolism, biosynthesis of metabolites and bioconversions, regulation of enzyme production includingfermentation kinetics and continuous culture. Other chapters deal with kinetics and engineering of medium sterilization, aeration and agitation, scale-up and instrumentation and control. Three concluding chapters are devoted to enzymes, their isolation, kinetics, immobilization and use in enzyme reactors. It is these last three chapters that many biochemists will find useful both for teaching and researchpurposes. Enzyme isolation is given a theoretical and practical treatment and many techniques of general interest to biochemists are dealt with in relation to small-scale and large-scale use. These include disruption, precipitation, centrifugation (including zonal), ultrafiltration, and chromatography. Finishing operations include desalting, concentration, drying, storage, purify, formulation, andbiosafety considerations. In the next chapter on kinetics and immobilization, a good treatment is presented of diffusional problems in enzyme kinetics. Much has been written and taught on this subject, but some aspects including apparent stabilization needed further consideration. The use of immobilized enzymes as tools is rapidly becoming part of the biochemists and chemists repertoire, foranalytical and bioconversion techniques. Up-to-date appraisal of this is therefore very welcome, as is the final chapter on the kinetics of immobilized enzyme reactors, which often seem unexpected to classic enzyme kineticists. This book is useful to biochemistry teachers and researchers for teaching courses to students in Industrial Biochemistry. This is an area where the reviewer has experienced...