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Milk Protein MILK PROTEIN Edited by Walter L. Hurley Milk Protein http://dx.doi.org/10.5772/2933 Edited by Walter L. Hurley Contributors Gabriella Pinto, Simonetta Caira, Marina Cuollo, Sergio Lilla, Lina Chianese, Francesco Addeo, Haiyan Sun, Håvard Jenssen, Teresa Treweek, Marcel Jøhnke, Torben E. Petersen, Tomoko Shimamura, Hiroyuki Ukeda, Bärbel Lieske, Simonetta Caira, Rosa Pizzano, Paolo Polidori, Silvia Vincenzetti, Joanna Barłowska, Anna Wolanciuk, Zygmunt Litwińczuk, Jolanta Król, Gema Lucia Zambrano-Burbano,Yohanna Melissa Eraso-Cabrera, Carlos Eugenio Solarte-Portilla, Carol Yovanna Rosero-Galindo, Massimo Bionaz, Walter Hurley, Juan Loor, Edyta Molik, Genowefa Bonczar, Tomasz Misztal, Aneta Żebrowska and Dorota Zięba Published by InTech Janeza Trdine 9, 51000 Rijeka, Croatia Copyright © 2012 InTech All chapters are Open Access distributed under the Creative Commons Attribution 3.0 license, which allows users to download, copy and build upon published articles even for commercial purposes, as long as the author and publisher are properly credited, which ensures maximum dissemination and a wider impact of our publications. After this work has been published by InTech, authors have the right to republish it, in whole or part, in any publication of which they are the author, and to make other personal use of the work. Any republication, referencing or personal use of the work must explicitly identify the original source. Notice Statements and opinions expressed in the chapters are these of the individual contributors and not necessarily those of the editors or publisher. No responsibility is accepted for the accuracy of information contained in the published chapters. The publisher assumes no responsibility for any damage or injury to persons or property arising out of the use of any materials, instructions, methods or ideas contained in the book. Publishing Process Manager Tanja Skorupan Typesetting InTech Prepress, Novi Sad Cover InTech Design Team First published September, 2012 Printed in Croatia A free online edition of this book is available at www.intechopen.com Additional hard copies can be obtained from [email protected] Milk Protein, Edited by Walter L. Hurley p. cm. ISBN 978-953-51-0743-9 Contents Preface IX Section 1 Bioactivity of Milk Peptides 1 Chapter 1 Bioactive Casein Phosphopeptides in Dairy Products as Nutraceuticals for Functional Foods 3 Gabriella Pinto, Simonetta Caira, Marina Cuollo, Sergio Lilla, Lina Chianese and Francesco Addeo Chapter 2 Milk Derived Peptides with Immune Stimulating Antiviral Properties 45 Haiyan Sun and Håvard Jenssen Section 2 Novel Functions of Milk Proteins 83 Chapter 3 Alpha-Casein as a Molecular Chaperone 85 Teresa Treweek Chapter 4 The Alpha-Lactalbumin/Oleic Acid Complex and Its Cytotoxic Activity 119 Marcel Jøhnke and Torben E. Petersen Section 3 Processing on Milk Proteins 145 Chapter 5 Maillard Reaction in Milk – Effect of Heat Treatment 147 Tomoko Shimamura and Hiroyuki Ukeda Chapter 6 Complexation Between Casein Micelles and Whey Protein by Indirect UHT- Processing of Milk: Influence of Surface Hydrophobicity and Dye-Binding Characteristics of Micelles in Relationship with Their Physico-Functionality 159 Bärbel Lieske VI Contents Section 4 Milk Protein Allergy 171 Chapter 7 Allergenicity of Milk Proteins 173 Simonetta Caira, Rosa Pizzano, Gianluca Picariello, Gabriella Pinto, Marina Cuollo, Lina Chianese and Francesco Addeo Chapter 8 Protein Profile Characterization of Donkey Milk 215 Paolo Polidori and Silvia Vincenzetti Section 5 Genetic Diversity 233 Chapter 9 Milk Proteins' Polymorphism in Various Species of Animals Associated with Milk Production Utility 235 Joanna Barłowska, Anna Wolanciuk, Zygmunt Litwińczuk and Jolanta Król Chapter 10 Relationship Between Kappa Casein Genes (CSN3) and Industrial Yield in Holstein Cows in Nariño-Colombia 265 Gema Lucia Zambrano-Burbano,Yohanna Melissa Eraso-Cabrera, Carlos Eugenio Solarte-Portilla and Carol Yovanna Rosero-Galindo Section 6 Regulation of Milk Protein 283 Chapter 11 Milk Protein Synthesis in the Lactating Mammary Gland: Insights from Transcriptomics Analyses 285 Massimo Bionaz, Walter Hurley and Juan Loor Chapter 12 The Effect of the Photoperiod and Exogenous Melatonin on the Protein Content in Sheep Milk 325 Edyta Molik, Genowefa Bonczar, Tomasz Misztal, Aneta Żebrowska and Dorota Zięba Preface Milk evolved as a means of providing for the postnatal needs of the developing mammalian neonate. Any perception that milk is a simple, homogeneous fluid does not adequately acknowledge the remarkable array of complex activities and functionalities of its constituent components. Milk composition and the components of milk can be studied and discussed from a range of perspectives, such as their importance to the nursing young, their biochemical, molecular, and physicochemical properties, the mechanisms that are responsible for their synthesis and secretion in the mammary gland, the factors that regulate and affect their variable presence in milk, and their importance as a food source for humans. Each of these interrelated perspectives in turn provides the foundation for diverse and active areas of research and innovation. This book provides insights into a wide range of topics related to milk protein. The milk-specific proteins evolved in such a manner as allow them to be synthesized and secreted rapidly in the mammary gland, ingested rapidly by the neonate, and digested rapidly in the neonatal gastrointestinal tract. From synthesis in the mother’s mammary gland to intestinal absorption in the nursing neonate, intact milk protein exists only for a relatively few hours. In spite of their apparent transient nature, the proteins found in milk and their digestion products can significantly impact the physiological and immunological status of the consumer of the milk through a range of mechanisms. Milk proteins also provide the foundational components responsible for many milk- derived food products with shelf lives that can reach to weeks and months, thereby dramatically extending their nutritional and functional value. The broad spectrum of complex processes responsible for regulating the synthesis and secretion of milk proteins in the mammary gland provides yet another exciting dimension to the study of these special proteins. The collective contributions contained in these chapters will provide significant value to readers who are interested in dairy foods, milk chemistry, cheese production, human health, neonatal development, lactation and mammary gland biology, milk protein production, and other related areas. The chapters of this book discuss and explore a broad range of topics related to milk protein. The bioactivity of casein phosphopeptides found in milk products and the potential of those peptides as nutraceuticals are explored, as are the antiviral properties of milk proteins and their X Preface peptides. A number of novel functions have been described for some of the milk proteins, as reviewed in a chapter on the potential role of alpha-casein as a molecular chaperone, and further expanded in a chapter that discusses the structure and proposed mechanisms of action of the alpha-lactalbumin/oleic acid complex referred to as HAMLET. Processing of milk that involves heat can have a profound impact on milk protein. Examples are provided in a chapter that evaluates alternative methods for testing for Maillard reaction products, and in another chapter examining complexes between casein micelles and whey protein that occur in response to indirect ultra-high temperature processing. The allergenicity of milk proteins and the mechanisms that underlie their allergenicity are reviewed, as is the potential of using milk from alternative species in cases of cow milk protein allergy. Genetic variation among milk proteins from dairy species is thoroughly reviewed in these chapters. Another chapter applies those concepts in examining the impact of specific genetic variants of kappa-casein on cheese yield. Novel insights into milk proteins synthesis are revealed in one chapter through transcriptomic analyses of milk protein gene expression, while the role of photoperiod in regulating milk protein content is discussed in another chapter. I want to give special thanks to the authors for taking the time and effort to prepare their contributions to this book. Their chapters provide a wealth of knowledge of this diverse topic. They have been generous in sharing many interesting insights and novel concepts. I also want to thank the staff from Intech for their outstanding help and guidance in making this book a reality, and to Intech for the opportunity to edit this book. Walter L. Hurley Professor, Lactation Biology Department of Animal Sciences University of Illinois Urbana, Illinois USA Section 1 Bioactivity of Milk Peptides Chapter 1 Bioactive Casein Phosphopeptides in Dairy Products as Nutraceuticals for Functional Foods Gabriella Pinto, Simonetta Caira, Marina Cuollo, Sergio Lilla, Lina Chianese and Francesco Addeo Additional information is available at the end of the chapter http://dx.doi.org/10.5772/50725 1. Introduction Nutraceuticals, a term combining the words “nutrition” and “pharmaceutical”, is a food or food product that provides medical or health benefits including the prevention and treatment of diseases. A functional food essentially provides a health benefit beyond the basic nutrition, whereas nutraceutical is used to describe an isolated or concentrated molecular extract of bioactive compounds. Milk is a unique food
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