Barley

Chemistry and Technology, Second Edition

Peter R. Shewry, Steven E Ullrich, Peter R Shewry

• Publisher: Woodhead Publishing and AACC International Press
• Year: 2014
• Print ISBN: 9781891127793
• eBook ISBN: 9780128123690
• Topic: Technology & Engineering
• Subtopic: Food Science
• Index: Technology & Engineering

Barley: Chemistry and Technology, Second Edition is an important resource for any cereal chemist, food scientist, or crop scientist who needs to understand the development, structure, composition, and end-use properties of the barley grain for cultivation, trade, and utilization.Editors Peter R. Shewry and Steven E. Ullrich bring together a wide range of international authorities on barley to create this truly unique, encyclopedic reference work that covers the massive increase in barley knowledge over the past 20 years, since the first edition of this book was published. Barley: Chemistry and Technology, Second Edition offers the latest coverage of barley's applications in milling, breeding, and production for food, feed, malting, brewing, distilling, and biofuels. It delivers a complete update of the latest knowledge of barley's many components, from the genetic and molecular level to its many constituents, such as proteins, carbohydrates, arabinoxylans, minerals, lipids, terpenoids, phenolics, and vitamins.This important book also includes chapters on barley's plant and grain development from both the physiological and genetic perspectives, making it an important resource not only for cereal and food scientists but also for crop scientists involved in breeding, agronomy, and related plant sciencesNew coverage includes: - Updated, comprehensive knowledge on barley's components, including proteins, carbohydrates, arabinoxylans, and bioactive effects- New end-use ideas for barley as an ingredient in food products- Nonfood industrial applications for barley, including biofuels- A new chapter on barley's health benefits- Molecular breeding for malting quality

Chapter 1

The Barley Crop: Origin and Taxonomy, Production, and End Uses

Steven E. Ullrich, Deptment of Crop and Soil Sciences, Washington State University, Pullman, Washington, U.S.A.

ORIGIN AND TAXONOMY OF BARLEY

The origins of almost all plant species, including the major crop species, and the origins of domestication of crop species are ancient, far predating the human understanding of such things. As such, the determination of the origins of crop species relies on evidence from the archeological record and on scientific investigation using the most up-to-date technologies available at the time, for example, from plant anatomy and morphology, biochemistry, genetics, and agriculture. Therefore, our knowledge and even theories of crop origin and taxonomy are frequently incomplete and subject to periodic change. This is definitely the case for barley (Hordeum vulgare L.), one of the most ancient of crop species, which is currently considered to be among the world’s first crop domesticates. Whereas barley domestication was once thought to have occurred as a single event in the Fertile Crescent of the Middle East at least 10,000 years ago, it is now thought that multiple domestications occurred within the Fertile Crescent (Zeder 2008), with further domestications about 1,500–3,000 km further east in central Asia (Azhaguvel and Komatsuda 2007, Morrell and Clegg 2007).

One approach to determining whether a plant species has been domesticated is the presence, in archeological samples, of morphological traits resulting from genetic changes (natural or caused by humans) that favor agricultural production (von Bothmer et al 2003b). In the case of barley, such domestication traits include 1) the presence of a nonbrittle rachis that prevents the spike from shattering and the grain from scattering upon maturity (Fig. 1.1); 2) the change from a two-rowed spike in the wild progenitor barley (H. vulgare subsp. spontaneum) (Fig. 1.2) to the six-rowed spike in H. vulgare subsp. vulgare (Fig. 1.3); and 3) naked or hull-less kernels (Fig. 1.4), which also do not occur in wild barley. Hull-less kernels facilitate the use of barley for human food because of the reduced insoluble fiber in the hull. Other domestication traits found in barley samples from parts of the world away from the regions of origin include 4) a reduced vernalization requirement and 5) photoperiod insensitivity that facilitates adaptation to different environments and climates (Salamini et al 2002).

Fig. 1.1 Illustrations of a nonbrittle, nonshattering spike (A) and brittle, shattering spikes (B) of wild barley (Hordeum vulgare subsp. spontaneum), which probably represent one of the first selections by humans that began the domestication process of barley. (Courtesy of Brian Steffenson, University of Minnesota; used by permission)

Fig. 1.2 Two-rowed barley spikes of Hordeum vulgare subsp. vulgare, which were inherited directly from wild barley (H. vulgare subsp. spontaneum). (Courtesy of Patrick M. Hayes, Oregon State University; used by permission)

Fig. 1.3 Six-rowed barley spikes of Hordeum vulgare subsp. vulgare, selected from the two-rowed type sometime during the domestication process. (Courtesy of Patrick M. Hayes, Oregon State University; used by permission)

Fig. 1.4 Hulled (A) and hull-less (B) barley kernels of Hordeum vulgare subsp. vulgare. Hull-less kernels were selected sometime during the domestication process. (Courtesy of Byung-Kee B...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• Contributors
• Preface to the Second Edition
• Preface to the First Edition
• Chapter 1: The Barley Crop: Origin and Taxonomy, Production, and End Uses
• Chapter 2: Barley Grain: Development and Structure
• Chapter 3: Genetic and Molecular Aspects of Barley Grain Development
• Chapter 4: Barley Grain Carbohydrates: Starch and Cell Walls
• Chapter 5: Barley Arabinoxylans: Molecular, Physicochemical, and Functional Properties
• Chapter 6: Barley Grain Proteins
• Chapter 7: Minor Components of the Barley Grain: Minerals, Lipids, Terpenoids, Phenolics, and Vitamins
• Chapter 8: Malting, Brewing, and Distilling
• Chapter 9: Barley Foods and Public Health
• Chapter 10: Processing of Barley Grain for Food and Feed
• Chapter 11: Use of Barley Grain and Straw for Biofuels and Other Industrial Uses
• Chapter 12: Molecular Breeding for Malting Quality
• Index