Yeast Technology

Yeasts are the active agents responsible for three of our most important foods - bread, wine, and beer - and for the almost universally used mind/ personality-altering drug, ethanol. Anthropologists have suggested that it was the production of ethanol that motivated primitive people to settle down and become farmers. The Earth is thought to be about 4. 5 billion years old. Fossil microorganisms have been found in Earth rock 3. 3 to 3. 5 billion years old. Microbes have been on Earth for that length of time carrying out their principal task of recycling organic matter as they still do today. Yeasts have most likely been on Earth for at least 2 billion years before humans arrived, and they playa key role in the conversion of sugars to alcohol and carbon dioxide. Early humans had no concept of either microorganisms or fermentation, yet the earliest historical records indicate that by 6000 B. C. they knew how to make bread, beer, and wine. Earliest humans were foragers who col lected and ate leaves, tubers, fruits, berries, nuts, and cereal seeds most of the day much as apes do today in the wild. Crushed fruits readily undergo natural fermentation by indigenous yeasts, and moist seeds germinate and develop amylases that produce fermentable sugars. Honey, the first con centrated sweet known to humans, also spontaneously ferments to alcohol if it is by chance diluted with rainwater. Thus, yeasts and other microbes have had a long history of 2 to 3.

Yeasts are the active agents responsible for three of our most important foods - bread, wine, and beer - and for the almost universally used mind/ personality-altering drug, ethanol. Anthropologists have suggested that it was the production of ethanol that motivated primitive people to settle down and become farmers. The Earth is thought to be about 4. 5 billion years old. Fossil microorganisms have been found in Earth rock 3. 3 to 3. 5 billion years old. Microbes have been on Earth for that length of time carrying out their principal task of recycling organic matter as they still do today. Yeasts have most likely been on Earth for at least 2 billion years before humans arrived, and they playa key role in the conversion of sugars to alcohol and carbon dioxide. Early humans had no concept of either microorganisms or fermentation, yet the earliest historical records indicate that by 6000 B. C. they knew how to make bread, beer, and wine. Earliest humans were foragers who col lected and ate leaves, tubers, fruits, berries, nuts, and cereal seeds most of the day much as apes do today in the wild. Crushed fruits readily undergo natural fermentation by indigenous yeasts, and moist seeds germinate and develop amylases that produce fermentable sugars. Honey, the first con centrated sweet known to humans, also spontaneously ferments to alcohol if it is by chance diluted with rainwater. Thus, yeasts and other microbes have had a long history of 2 to 3.

Basic research is here applied to solve practical problems and to bring the reader up-to-date on recent developments of most aspects of yeast-based industries. Main topics cover: the brewing and distilling industries, wine-making and the nature of winery yeasts, food yeasts, spoilage yeasts, non-saccharomyces yeasts, their substrates and products; the construction of improved industrial yeast strains by site-directed mutagenesis, production of heterologous proteins by genetically-engineered yeasts, and factors affecting yields of such proteins as well as the use of calorimetry in control systems for yeast fermentations. This sourcebook will prove useful to everybody involved in technical applications of yeasts.

This classic series covers the complete biology and biochemistry of the yeasts in six volumes. Volume 5 addresses the major areas of yeast technology relevant to the food, pharmaceutical, and biotechnology industries. * SPECIAL FEATURES: * Final volume of a comprehensive research level edited treatise covering biochemistry physiology, technology of yeasts. The book will cover the major areas of yeast technology relevant to the food, pharmaceutical and biotechnology industries. Yeast are highly versatile organisms, particularly suitable for industrial purposes - this book will be of interest to many.

Yeasts play a crucial role in the sensory quality of a wide range of foods. They can also be a major cause of food spoilage. Maximising their benefits whilst minimising their detrimental effects requires a thorough understanding of their complex characteristics and how these can best be manipulated by food processors. Yeasts in food begins by describing the enormous range of yeasts together with methods for detection, identification and analysis. It then discusses spoilage yeasts, methods of control and stress responses to food preservation techniques. Against this background, the bulk of the book looks at the role of yeasts in particular types of food. There are chapters on dairy products, meat, fruit, bread, soft drinks, alcoholic beverages, soy products, chocolate and coffee. Each chapter describes the diversity of yeasts associated with each type of food, their beneficial and detrimental effects on food quality, methods of analysis and quality control. With its distinguished editors and international team of over 30 contributors, Yeasts in food is a standard reference for the food industry in maximising the contribution of yeasts to food quality. Describes the enormous range of yeasts together with methods for detection, identification and analysis Discusses spoilage yeasts, methods of control and stress responses to food preservation techniques Examines the beneficial and detrimental effects of yeasts in particular types of food, including dairy products, meat, fruit, bread, soft drinks, alcoholic beverages, soy products, chocolate and coffee

As a group of microorganisms, yeasts have an enormous impact on food and bev- age production. Scientific and technological understanding of their roles in this p- duction began to emerge in the mid-1800s, starting with the pioneering studies of Pasteur in France and Hansen in Denmark on the microbiology of beer and wine fermentations. Since that time, researchers throughout the world have been engaged in a fascinating journey of discovery and development – learning about the great diversity of food and beverage commodities that are produced or impacted by yeast activity, about the diversity of yeast species associated with these activities, and about the diversity of biochemical, physiological and molecular mechanisms that underpin the many roles of yeasts in food and beverage production. Many excellent books have now been published on yeasts in food and beverage production, and it is reasonable to ask the question – why another book? There are two different approaches to describe and understand the role of yeasts in food and beverage production. One approach is to focus on the commodity and the technology of its processing (e. g. wine fermentation, fermentation of bakery products), and this is the direction that most books on food and beverage yeasts have taken, to date. A second approach is to focus on the yeasts, themselves, and their bi- ogy in the context of food and beverage habitats.