Jurgen Frohlich – författare

The second edition of the book begins with the description of the diversity of wine-related microorganisms, followed by an outline of their primary and energy metabolism. Subsequently, important aspects of the secondary metabolism are dealt with, since these activities have an impact on wine quality and off-flavour formation. Then chapters about stimulating and inhibitory growth factors follow. This knowledge is helpful for the growth management of different microbial species. The next chapters focus on the application of the consolidated findings of molecular biology and regulation the functioning of regulatory cellular networks, leading to a better understanding of the phenotypic behaviour of the microbes in general and especially of the starter cultures as well as of stimulatory and inhibitory cell-cell interactions during wine making. In the last part of the book, a compilation of modern methods complete the understanding of microbial processes during the conversion of must towine.This broad range of topics about the biology of the microbes involved in the vinification process could be provided in one book only because of the input of many experts from different wine-growing countries.

The ancient beverage wine is the result of the fermentation of grape must. This n- urally and fairly stable product has been and is being used by many human societies as a common or enjoyable beverage, as an important means to improve the quality of drinking water in historical times, as therapeutical agent, and as a religious symbol. During the last centuries, wine has become an object of scientific interest. In this respect different periods may be observed. At first, simple observations were recorded, and subsequently, the chemical basis and the involvement of microorg- isms were elucidated. At a later stage, the scientific work led to the analysis of the many minor and trace compounds in wine, the detection and understanding of the biochemical reactions and processes, the diversity of microorganisms involved, and the range of their various activities. In recent years, the focus shifted to the genetic basis of the microorganisms and the molecular aspects of the cells, including metabolism, membrane transport, and regulation. These different stages of wine research were determined by the scientific methods that were known and available at the respective time. The recent “molecular” approach is based on the analysis of the genetic code and has led to significant results that were not even imaginable a few decades ago. This new wealth of information is being presented in the Biology of Microorganisms on Grapes, in Must, and in Wine.