Cereal fatty acid composition

The fatty acids of cereal lipids are generally linoleate, palmitate, oleate, a-linolenate and stearate in order of abundance. Considerable variations in the fatty acid compositions of bulk lipids have been achieved by breeding in barley, maize and oats. The fatty acid content and distribution in cereals has been recently reviewed (cf. Barnes, 1983). 

The lipids are preferentially stored in the germ which, in the case of com and wheat, serves as a source for oil production (cf. 14.3.2.2.4). Lipids are stored to a smaller extent in the aleurone layer. Cereal lipids do not differ significantly in their fatty acid composition (Table 15.31). Linoleic acid always predominates. Close attention has been given to wheat lipids since they greatly influence baking quality ttnd they have therefore been studied thoroughly. 

Table 15.31. Average fatty acid composition of acyl lipids of cereals (weight-%)...

TABLE 3.5 Fatty Acid Composition of Cereal Grains.101... 

Ivanyi, L, 2006. Effect of genotype and environmental on the oil content and fatty acid composition of hempseed. Cereal Res. Commun. 34, 493—196. 

Sridhar, R. and Lakshminarayana, G. (1994). Contents of total lipids and lipid classes and composition of fatty acids in small millets Foxtail (Setaria italica), Proso (Panicum mili-aceum), and finger (Eleusine coracana). Cereal Chem. 71, 355-359. 

The oil content of oats is higher than that of most of the other cereal grains, and about 60 per cent of it is present in the endosperm. As mentioned earher, the oil is rich in unsaturated fatty acids and has a softening effect on the body fat.The range in dry matter composition of 171 samples of oat grain harvested in Wales is shown in Table 22.2. 

Stubbs TL, Kennedy AC, Reisenauer PE, Burns JW (2009) Chemical composition of residue from cereal crops and cultivars in dryland ecosystems. Agron J 101 538-545 Sylvia DM, Fuhrmann JJ, Hartel PG, Zuberer DA (2004) Principles and application of soil microbiology, 2nd edn. Prentice Hall, New Jersey, NJ Tang CS, Waiss AC (1978) Short-chain fatty acids as growth inhibitors in decomposing wheat straw. J Chem Ecol 4 225-232... 

In plants, fats are mainly found in seeds, but also in the pericarp layers, the outside exocarp layer (peel), the middle layer (pith) and the inner endocarp layer. Fat is also present in the germs of seeds, in which starch is the main reserve substance (e.g. the germ of cereals). Fat composition is due mainly to the fatty acid content, but specific properties of lipases also play a role. 

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