Seed Morphology, Composition, and Quality

Publisher Summary This chapter gives a description of the structure, physical properties, and composition of canola seeds and includes some information on the composition and structure of non-canola types, particularly where the difference is crucial. All seeds contain moisture in the form of water. The amount of moisture in mature seeds depends on the relative humidity and temperature. Canola is principally marketed for its oil and thus oil content is the most important parameter in assessing canola quality. One of the best-known features of canola is the reduction of erucic acid from its original high level of approximately 40% to today's level of less than 1%. Canola and other Brassica oilseeds contain three major classes of proteins: Albumins or water-soluble proteins, which include enzymes that are responsible for the metabolic activities of the seed; Globulins or salt-soluble proteins, which constitute the major storage proteins in the seed; and Oleosins, which are the structural proteins of the oil bodies and may account for 20% of the seed protein. Canola and other Brassica oilseeds may be considered to contain carbohydrates at three levels of complexity: soluble sugars, insoluble carbohydrates, and fiber.