Preface

Chapter 8 **Effects of Gamma Radiation on Essential Oils: A Review 179**

Chapter 9 **Gamma Rays' Effect on Food Allergen Protein 203** Marcia Nalesso Costa Harder and Valter Arthur

Carvalho Alcântara

**VI** Contents

Clináscia Rodrigues Rocha Araújo, Geone Maia Corrêa, Viviane Gomes da Costa Abreu, Thiago de Melo Silva, Aura María Blandón Osorio, Patrícia Machado de Oliveira and Antônio Flávio de

> Gamma radiation, the unseen energy that affected human life over decades, was discovered by the French chemist and physicist Paul Villard in 1900, 4 years after the discovery of the natural radioactivity by Henry Becquerel. X-rays were discovered by Wilhelm Roentgen in 1995; shortly, two types of radiation were discovered before the discovery of gamma radia‐ tion, alpha particles by Ernest Rutherford in 1899 and beta particles by Henry Becquerel in 1896, and hence the third type of radiation was named by Rutherford as "gamma rays" in 1903 by analogy with alpha and beta rays.

> Gamma rays are highly energetic electromagnetic radiation and like other things have many useful applications and some hazards if improperly used. A day after another, new applica‐ tions of gamma rays emerge, leading to more convenience for the human life and help in facing challenges in different disciplines such as in health, economy, culture, environment, and many others. Hence, there is always a need to know more about gamma rays.

> This book furnishes information regarding some applications of gamma rays. It contains three sections: the first section "Gamma Ray Spectrometry" describes the use of gamma ray spectrometry in the investigation of environmental and food samples, followed by a review of studies on the dead time in gamma ray spectrometry with a newly suggested model for the evaluation of the dead time, and finally a chapter on plastic scintillators and pseudo‐ gamma spectrometry.

> The second section, which is titled "Gamma Rays in Space," is composed of two chapters: the first gives an overview of gamma rays from space highlighting the gamma ray bursts, and the second one is concerned with the extragalactic gamma ray background and the the‐ ories describing its origin.

> The last section entitled "Recent Applications of Gamma Rays" is composed of six subsec‐ tions on different and sometimes unusual applications of gamma radiation such as mutation breeding, analysis of soil and minimizing the problem of allergen protein in food in addition to a detailed review of the effect of gamma rays on essential oils.

> The editor thanks all authors of this book for their valuable contributions and for their patience throughout the editing processes and in the same time wishes that readers of this book will find it useful and interesting. Finally, I hope this book adds a value to the scientific library.

> > **Prof. Dr. Ahmed M. Maghraby** Ionizing Radiation Metrology Laboratory National Institute of Standards, Giza, Egypt
