Errata

Journal of Essential Oil Research: JEOR, Jul/Aug 2004

In the March/April 2004 [volume 16(2)] issue of thejournal of Essential oil Research, the editors did not provide ISBN and publisher name for Theresa Chamblee s review of "Citrus, The genus Citrus" (p 80-81). The revised review appears below:

Book Review

Citrus, The genus Citrus

edited by Giovanni Dugo and Angelo Di Giacomo

Review by Theresa Chamblee, The Coca-Cola Company

Routledge (Taylor & Francis Group), ISBN: 0415284910

Volume 26 of the Medicinal and Aromatic Plants-Industrial Profiles Series is dedicated to the genus Citrus. The purpose of the series is to provide a format to bring together the wide range of information concerning production, quality control, chemistry, and uses for commercially significant medicinal and aromatic plants. Much of this information is scattered throughout the literature in journals, books and meeting proceedings. A compilation of all this information in one place is useful for the experienced citrus expert as well as the newcomer to the field. As well-known area specialists in the citrus field, editors Dugo and Di Giacomo have done a very good job of fulfilling the series' mission with Volume 26. While the majority of the contributors of the volume are from the editors' native Italy, the work provides a good review of worldwide research and information available on Citrus.

The citrus industry has three major commercial products: fresh fruit, juice and essential oil. The current volume focuses on the essential oil. There is one chapter each on juice production (chapter 7) and citrus by-products (chapter 11), with the remaining work dedicated to oils. The book covers four major areas: History, Cultivation/Processing, Composition and Uses/Applications.

History (chapters 1,2 and 5): The book provides an interesting and thorough review of the history and development of citrus plants starting in China in 1027 BC up through the centuries to today, where citrus species and varieties can be found on every continent. As a result of the wide dissemination of citrus throughout the world and the occurrence of natural hybrids, many varieties exist. Chapter 2 provides a useful review of citrus botany and classification.

Cultivation/processing (chapters 3, 4, 6-10 and 16): Agricultural information such as soil, fertilization, irrigation, pruning, diseases and pests important to citrus cultivation are covered in chapters 3 and 4. The book provides a good general overview of these topics, keeping in mind that geographic and personal preferences can come into play in these areas. Citrus production, with an emphasis on essential oil, is covered in detail in chapters 6-10, while chapter 16 explains and reviews secondary processing techniques such as washing, folding, and column chromatography. The discussion is quite extensive with a slight bias to the Italian industry. The authors provide many classic, as well as recent, literature reports on the subject and also include possible methods of the future such as supercritical CO2 extraction. Even though CO2 extraction has benefits over methods utilizing solvents, the book reports that there are as yet no commercially available CO2 concentrated citrus oils. In general, the discussion is quite informative and will be a useful reference for students, flavorists interested in citrus cultivation and production or someone entering into the citrus business.

Composition (chapters 12-22): The majority of the book is devoted to composition of citrus essential oils. There is a large amount of information available ranging from volatile, nonvolatile, chiral compounds, adulterants and common contaminants. Advanced analytical techniques have been utilized and developed to study the composition and authenticity of essential oils such as multidimensional GC and stable isotope ratio M S. These techniques are reviewed in chapter 12 followed by a review of the composition of the major citrus essential oils of commercial significance. The following oils are discussed in detail (chapters 13, 15, 17- 21):

The discussion includes historical perspective, semi-quantitative data (mostly area %) and comparison of commercial oils vs. lab-extracted samples, when available. Chapter 14 provides an interesting review of less common citrus species with inclusion of data for peel, leaf, flower and juice oils of sour orange, clementine, pummelo, combava, rough lemon, yuzu, calamondin, citron, etrog and unshiu mikan. The essential oil composition part of the book is probably the most detailed and thorough section of the book and will be most useful to flavorists and perfumers.

Uses and application (chapters 24-28): This section only briefly covers the use of citrus oils in flavor and perfume applications, their most common application. The authors of chapter 24 discuss the important topic of citrus oil stability in flavor applications; however, the scheme showing citral degradation has some errors. There are probably more accurate references to this topic that the authors have overlooked. The chapters describing the use of citrus essential oils in traditional medicine and their antimicrobial and antitumor activity are an interesting and uncommon addition to the volume. Legislative issues concerning the use of citrus oils are also reviewed.