Canola (eBook)

Chemistry, Production, Processing, and Utilization

James K. Daun, Michael N.A. Eskin, Dave Hickling (Herausgeber)

eBook Download: PDF | EPUB

2015 | 1. Auflage
432 Seiten
Elsevier Science (Verlag)
978-0-12-804348-6 (ISBN)

Infos

This book gives a complete picture of the canola crop including its history, botany, genetics, distribution, breeding and biotechnology, production, processing, composition, nutritional properties and utilization of the seed, oil and meal, as well as an economic profile. While the main focus in this book is on canola of Canadian origin, its cousin crop oilseed rape will also be discussed to a lesser extent. The work provides up-to-date information on the crop and highlights areas where research and development is either needed or is in process. - Provides extensive information on the canola plant, including breeding, genetic engineering for trait development, and seed morphology and composition - Editors and contributors are global leaders in canola research and application - Offers a comprehensive overview of canola oil and meal composition, nutrition, and utilization

Textauszug

2

Botany and Plant Breeding

Axel Diederichsen1 and Peter B.E. McVetty2,     1Plant Gene Resources of Canada, Agriculture and Agri-Food Canada, Saskatchewan, Canada; 2Department of Plant Science, University of Manitoba, Winnipeg, Manitoba, Canada

Introduction

Interest in the genus Brassica as an oilseed for edible and industrial oils uses is a consequence of its high oil content and high protein meal left over after oil extraction (Röbbelen, 1991) and because brassica oilseed species (BOS) are adapted to temperate climatic zones and are able to germinate and grow at low temperatures (Kondra et al., 1983; Morrison et al., 1989), with spring and winter habit forms. Several BOS yield edible and industrial oils and are the third most important source of vegetable oils after palm and soybean (Gupta & Pratap, 2009). B. carinata (Ethiopian mustard, Abyssinian mustard), B. napus (oilseed or Swede rape/rapeseed), and B. juncea (Indian mustard, brown mustard) are amphidiploids combining chromosome sets of the diploid species B. rapa (turnip rape), B. nigra (black mustard), and B. oleracea (cabbage, kale) (U, 1935). Several BOS including B. carinata, B. juncea, B. napus, and B. rapa naturally produce seed oil moderate to high in erucic acid (22:1 cis-13) content and moderate to high in protein content in the seed meal after oil extraction (Downey & Röbbelen, 1989). Ranges of erucic acid content in these species have been reported by Velasco et al. (1998) as follows: B. carinata, 29.6–51.0%; B. juncea, 15.5–52.3%; B. napus, 5.6–58.1%; and B. rapa, 6.5–61.5%. Black mustard and kale also naturally produce seed oil with a range in erucic acid content. Tahoun et al. (1999) have reported erucic acid content ranges for B. nigra as 30.3–45.0% and for B. oleracea as 0.1–62.0%. The plants and seeds of all brassica oilseeds contain glucosinolates, which are secondary metabolites that serve as chemical protectants (Mitten, 1992). Ranges of glucosinolate content in these species have been reported to be 20 to more than 200 μmol g−1 seed total glucosinolates for B. napus, B. oleracea, and B. rapa; 75 to more than 150 μmol g−1 seed total glucosinolates for B. carinata and B. nigra; and 100 to more than 200 μmol g−1 seed total glucosinolates for B. juncea (Röbbelen & Theis, 1980).

Different brassica oilseed species predominate in different regions of the world. In the warmer semitropical regions, B. juncea and B. rapa predominate, whereas in cooler temperate regions B. napus and B. rapa predominate. B. carinata is limited to Ethiopia and northeast Africa, whereas B. nigra is grown in Europe and Asia. B. nigra is currently grown exclusively as a condiment crop. B. oleracea is exclusively a vegetable crop produced globally. B. juncea is an important oilseed species in Asia as well as an important condiment crop in Canada that has recently been converted to a new Canadian edible oilseed crop (Potts et al., 2003). B. napus is the predominant oilseed species in Australia, Europe, Canada, and China, whereas B. juncea is the predominant species in India and northwest China. Winter B. napus types are grown in southern Europe, whereas spring B. napus and B. rapa types are grown in northern Europe (Gupta & Pratap, 2009). Winter B. rapa types, formerly grown in northern Europe, have been replaced by higher yielding winter B. napus types.

Evolution and Taxonomy of Brassica Oilseeds

Diversity of Cultivated Brassica Species and Closely Related Taxa

This section provides a brief overview of the evolution and genetic resources of the important cultivated BOS and some of the closely allied wild species. A wide range of geographic distribution, a tremendous range of different usages, and a corresponding enormous phenotypic range of diversity presented challenges for botanists in classifying and naming the diversity of cultivated brassica species. Homologous developments occurred in different species of this genus. For several usage groups, common names of brassica crops are not available in English because some uses have traditionally not been known to English-speaking cultures. Names such as “rapeseed” have been applied interchangeably for B. napus and B. rapa, the two traditional oilseed brassica species in Europe. In parts of western and southern Europe, the name “colza,” derived by contraction of the Dutch “kool” (cabbage) and “zaad” (seed), is also used for both species. The general term “mustard” can refer to all species for which seeds have been used as condiment, such as B. juncea, B. nigra, B. carinata, and Sinapis alba. The name “canola” was created in Canada in 1978 for marketing Canadian seeds of B. napus and B. rapa with low content of erucic acid and low content of glycosinolates (Canola Council of Canada, 2010). In the meantime, this seed quality has also been achieved in B. juncea (Rakow, 2004). These three species are now also marketed as canola in Canada. B. carinata, another oilseed brassica, has so far been excluded from being named canola. B. nigra, the traditional oilseed crop of the Indian subcontinent, has not been altered in its chemical properties, and the pungent taste of the seed oil that is due to glucosinolates is actually a desired quality in this region. Scientific names are also subject to change. For example, B. rapa has the synonym B. campestris, which was used more commonly in the past. All of these factors contribute to confusion in naming the diversity in brassica species. In addition to that, genetic exchange among many of the cultivated brassica taxa and related wild species is possible and has occurred, resulting in difficulties in distinguishing taxa and species and in inconsistencies in the names used for them. Therefore, this section emphasizes the importance of taxonomy as a tool for efficient communication about brassica oilseeds. This facilitates utilization, conservation, and understanding of this interesting crop group and their important relatives.

The only cultivated brassica species that has no distinct type for exclusive seed use is B. oleracea, which instead is very rich in diversity for vegetable, forage, and ornamental use. All usage groups of cultivated brassica species and some wild species are important genetic resources for plant breeding in oilseed brassicas. The genetic relationships among the cultivated taxa of the genus Brassica were studied by various cytologists in the beginning of the 20th century, and in 1935 U summarized the results by presenting what is frequently referred to as “U’s triangle” (see Chapter 1, Fig. 1.2; Helm, 1963; Mizushima, 1980). U’s concept has been extremely fruitful for understanding the evolution of the important brassica crops and has inspired much research and breeding activities in the genus Brassica (Snowdon, 2007). Three diploid brassica species, B. nigra (haploid number of chromosomes: n = 8), B. rapa (n = 10), and B. oleracea (n = 9), have been cultivated for a long time. Weedy types of B. nigra and B. rapa exist in the Mediterranean and Southwest Asia, and they are probably the ancestors of the cultivated types that arose very early in agriculture (Sinskaya, 1928; Hedge, 1976). The wild progenitors of the different cultivated B. oleracea types are the perennial subspecies of B. oleracea (Table 2.1). Yarnell (1956) and later Snogerup (1980) have proposed that different taxa of this group were involved in the evolution of the various vegetable types of the cultivated infraspecific taxa of B. oleracea because they all can be crossed with the cultivated taxa. The closest wild relative is the wild perennial cabbage of the European Atlantic coast, B. oleracea subsp. oleracea (Snogerup et al., 1980). In the case of B. rapa, independent domestications may have happened in West and East Asia, resulting in seed use and vegetable types, respectively (Sinskaya, 1928; Warwick et al., 2008). Later, these diploid species hybridized spontaneously with each other in areas where their geographical ranges of distribution overlapped, resulting in three amphidiploid bastards, B. juncea (n = 18), B. carinata (n = 17), and B. napus (n = 19), that are cultivated species of their own and do not occur as wild plants although they are sometimes weeds (see Chapter 1, Fig. 1.1). These hybridizations happened more recently. For the species B. napus,...

Produkt-Details

• Erscheint lt. Verlag: 13.8.2015
• Sprache: englisch
• Themenwelt: Technik ► Lebensmitteltechnologie
• ISBN-10: 0-12-804348-2 / 0128043482
• ISBN-13: 978-0-12-804348-6 / 9780128043486