Downloaded by 80.82.77.83 on May 1, 2017 | http://pubs.acs.org Publication Date: June 13, 2008 | doi: 10.1021/bk-2008-0983.pr001
Preface Consumers use color as an index for quality when purchasing foods and the color has to be "right". This is a given assumption in industry where considerable emphasis is given to color quality in purchase specification and quality assurance. In some instances, color assessment is done by qualitative visual inspection and sometimes with the aid of standardized color charts. Quantitative instrumental measurement of color is preferable in both research and industrial applications. Relatively simple spectrophotometric measurements are widely used, but are limited to homogenous transparent materials. More sensitive and accurate instru ment measurements using CIEL*a*b indices are increasingly being used, in research and industrial practices. These test methods can be adapted for much broader range of test materials. Presently the natural pigments (such as carotenoids, anthoyanins, chlorophylls, and betalains) are being intensely investigated because of their potential health benefits. The focus of this book, however, is on their relationship to color quality and not on their biological activity, absorption, metabolism, or safety. While chem ists take a disciplinary approach when investigating natural pigments and their relationship to food color quality, industry is typically organized along commodity lines. This book has taken a commodity approach in examining color quality, rather than examine pigments class by class. This book is the end product of an American Chemical Society (ACS) sponsored symposium, Color Quality of Fresh and Processed Foods, held in Atlanta, Georgia in March 2006. Symposium participants, who were invited because of their expertise in the fields, wrote the chapters. This list of authors includes several international experts, and efforts were made to have representation from industry and government as well as academia. A number of color figures are in this book, which add to its cost. It was not difficult to justify the use of color figures, however, in a book on color quality. Efforts were made to select color figures that made for a clearer presentation of the author's concepts and not just for decorative purposes.
xi Culver and Wrolstad; Color Quality of Fresh and Processed Foods ACS Symposium Series; American Chemical Society: Washington, DC, 2008.
Downloaded by 80.82.77.83 on May 1, 2017 | http://pubs.acs.org Publication Date: June 13, 2008 | doi: 10.1021/bk-2008-0983.pr001
The book opens with a section on Color Measurement where the basic principles and practical issues of color measurement are presented by authors from manufacturers of color measurement instruments and supplies. The scope of the following two sections, Fruit and Vegetables (10 chapters) and Beverages (6 chapters) reflects the bias of the two co organizers of the symposium and coeditors of the book. The section on Fruits and Vegetables addresses both fresh and processed foods and includes the perspective of the plant breeder as well as that from industrial and academic scientists. The section on Beverages reaffirms the justification for taking a commodity approach in this book. The acceptable methods for measuring color of beer and wine, for example, are heavily influenced by recommendations from professional trade associations. The three chapters in the section Meats and Seafood emphasize the importance of color quality in the trade of those commodities, and also the difficulties in measuring color in those complex matrices. The section Oils, Emulsions, Cereals, and Dairy Products incorporates a broad range of commodities with the chapters ranging from the fundamentals of measuring emulsion appearance to understanding the relationships between pigment composition and color stability of different products. Food colorants are given intense regulatory scrutiny because of a centuries-long history of disguising foods and food ingredients of inferior quality. In the past, some the added food colorants included toxic substances and led to human sickness and death. Another reason may be the widely held belief that color is cosmetic and unnecessary. Several authors in the book present convincing evidence that such a premise is false. Food regulations vary considerable from country to country, both in basic principles for colorant regulation and in very specific rules for use and labeling of individual colorants. The six chapters in the final section Regulatory Aspects give a very comprehensive update on colorant regulations in the United States, Europe, Central and South America, and Asia. The viewpoint from regulatory agencies is given along with that from manufacturers and users of food colorants. Although regulatory agencies and professional associations are striving for harmonization of food colorant regulations to facilitate trade, it is unlikely that this goal will be achieved very soon. While colorant regulations will continue to undergo change, this section provides a very clear picture of food colorant regulations at the present time. The symposium and the book would not have been possible without the generous financial contributions from organizations and companies.
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Culver and Wrolstad; Color Quality of Fresh and Processed Foods ACS Symposium Series; American Chemical Society: Washington, DC, 2008.
Downloaded by 80.82.77.83 on May 1, 2017 | http://pubs.acs.org Publication Date: June 13, 2008 | doi: 10.1021/bk-2008-0983.pr001
The funds provided travel support for several of the speakers and contributions were also used to partially underwrite the cost of the color figures in the book. We thank the following contributors: The A C S Division of Agricultural and Food Chemistry, Inc., San-I Gen EFI, B A S F , Color M A K E R , Danisco USA, Food Ingredient Solutions, G N T Europa, the International Association of Color Manufacturers, and Pepsi-Cola Company. W e also thank the authors and their affiliate organizations, as well as the many anonymous individuals who served as peer reviewers. Gordon Leggett and Arthur Lipman deserve special thanks, not only for their excellent chapters, but also for serving as invaluable sources during the discussion periods at the symposium. Also, a note of appreciation is expressed to Andreas Schieber and Florian Stintzing for being so timely with submission of their manuscripts.
Ronald E. Wrolstad Department of Food Science and Technology Wiegand Hall Oregon State University Corvallis, O R 07331
Catherine A. Culver Pepsi-Cola Company 100 Stevens Avenue Valhalla, N Y 10595
xiii Culver and Wrolstad; Color Quality of Fresh and Processed Foods ACS Symposium Series; American Chemical Society: Washington, DC, 2008.
