Canola meal composition

Composition of Canola Meal. Canola meal is an internationally traded commodity. Excellent summary information on canola meal composition has been developed to aid the animal feed industry (25). Canola meal contains 36-38% crude... 

Proximate and Amino Acid Composition of Canola Meal and Soybean MeaP... 

The proximate composition of canola/rapeseed varies among varieties as a result of both genetic makeup and growing conditions. As summarized in Table 4.3 [4], the oil content of canola is about twice that of soyabeans and contains much more fibre than soyabeans. The protein content of oil-free canola meal is only slightly lower than that of soyabeans. Canola is processed primarily for its oil, which makes up some 40% of the seed mass. It has an ideal fatty acid composition for human consumption, with a linoleic-to-linolenic acid ratio of approximately 2. After oil removal, the meal contains more than 40% protein with well-balanced amino acid composition. The essential amino acid composition, given in Table 4.4, indicates that canola protein is superior... 

Containing more than 35% protein with a well-balanced amino acid composition and desirable functionalities, canola meal certainly qualifies as a protein product. Due to the low levels of glucosinolates in the meal, it is a suitable feedstuff for livestock and poultry. Based on its nutrient content, canola meal is worth 70-75% of the value of soyabean meal for feeding poultry and about 75-80% of the same for feeding swine and ruminants, while the cost of canola meal was historically much less than 70% of that of soyabean meal [23]. 

Table I. Amino Acids Composition of Defatted Canola (Rapeseed) and Sunflower Meals (19)...

The magnitude of the variation in the composition of rapeseed oil and meal now commercially available has created a need for new terms to describe the products derived from rapeseed. The fatty acid composition of most edible vegetable oils such as soybean, sunflower, or cottonseed oils, varies within narrow limits. Thus, the species or commodity name (e.g., soybean oil) provides a reasonable description of the fatty add composition of soybean oil. In contrast, the erucic acid content of commercially available rapeseed oil may vary from near zero to 55%, and the oleic acid from 10 to more than 60%. A number of terms have been proposed or utilized to describe the new rapeseed oil whose fatty acid composition has been altered by the elimination of erucic acid these include low erucic acid rape-seed oil (LEAR), canbra, and canola. Similar terms such as high erucic acid rapeseed oil (HEAR) and common or traditional rapeseed oil have been used to describe rapeseed oil whose fatty acid composition includes substantial amounts of erucic acid. 

Most of the rapeseed produced in the Orient is of the traditional kind, high in both erucic acid and glucosinolates. Little attention appears to have been given to the development of canola cultivars. Perhaps the need to increase food supplies discourages the deployment of resources for work on quality. Prakash (1980) suggests that alteration of the composition of the oil and meal is one of a number of possible future trends in India. The recent increase in international contacts probably will stimulate the development of canola cultivars in China. 

So far, two processes involving membrane separation for canola protein isolation are considered promising, and both are currently under commercial development Researchers at the University of Toronto developed a membrane-based process for canola protein isolation from defatted meal [29,42], in which, after precipitation, the soluble proteins were ultraflltered to be concentrated and diaflltered for purification. Two protein isolates were produced precipitated and soluble, with a combined protein recovery of more than 70% of total meal protein. Both products were high in protein (>85%), low in phytates (<1%), essentially free of glucosinolates (<2 (xmol/g) and had desirable functional properties comparable to those of soy protein. While the methionine content of both protein isolates was similar to the reported values, the soluble product was found to have a higher level of lysine than any canola proteins obtained before, and the precipitated protein isolate was, on the other hand, farther enriched with leucine [43]. This amino acid composition makes them suitable for nse in infant formulae (Table 4.6). Despite their excellent nutritive quality. 

The protein composition of cereals is not snfflcient to sustain optimnm growth in most domestic animals. Thus, cereals are supplemented with protein meals that contain high amonnts of lysine and tryptophan. The most common protein meals are soybean, cottonseed, canola, and meat and fish meal. The use of meat and bone meal, and other animal protein meals snch as dried blood, is prohibited in several parts of the world because its consumption has been associated with mad cow disease. 

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