Oat grains

The annual productions of barley and oats average about 141 and 25 million metric tons in the world (11), respectively. Like com, most barley and oat grain is used for animal feed (about 70% of world production) (115). Today, the use of oat and barley in human foods is very limited. However, recent interests in oat- and barley-derived dietary fibers enriched in p-glucan create a great potential for functional foods, nutraceuticals, and other value-added product development from these grains. 

Oats Oat grain and oat oil contain both tocopherols and tocotrienols. The major tocols are a-tocopherol and a-tocotrienol. Significant variations occur in tocol composition of oat oil due to the oat variety and milling process used for the study. Total tocol content of oat oil varies from 175 ppm to 640 ppm (125). a-Tocopherol (20-82% of the total tocols), a-tocotrienol (16-51% of total tocols), 5-tocotrienols (0-12% of total tocols), and y-tocopherol (0-36% of total tocols) are the predominant tocol isomers reported in the oat oil. 

Presence of phytosterols in oat oil was first reported by Idler et al. in 1953 (128). Oat grain contains 35-60 mg phytosterols/100 g grain (127). Phytosterol content of oat oil varies between 0.19% to 0.32% (125). p-Sitosterol (40-70% of total sterols) is the major phytosterol in oats. A - and A -Avenasterol are the two other phytosterols that present in significant quantities in oats. Campesterol, stigmasterol, A -stigmasten-3p-ol, A -cholesten-3p-ol, and cholesterol were also present in oat grain. 

Oat grain (Avena sativa L.) from which the hulls have been removed (n = 51). Synonym dehulled oats, shelled oats. 

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. 

A group of about 40 amides derived from 5-hydroxyanthranilic or 5-hydroxy-4-methoxyanhranilic acids and cinnamic acids, trivially named avenanthramides, are important phytoalexins unique to oat grains Avena sativa, Poaceae). The dominant compounds are derivatives of 5-hydroxyanthranilic acid avenanthramide Bp derived from p-coumaric acid (also called avenanthramide A, 8-154), avenanthramide Be derived from caffeic acid (also called avenanthramide C) and avenanthramide Bf derived from ferulic acid (also called avenanthramide B). The main compound (40-132 mg/kg) is avenanthramide Bf (8-154). Approximately 6% of oat antioxidants are anthramides derived from caffeic acid. 

Common substrates. Ergot sclerotia ate most often found in small grains, including rye, barley, wheat, and oats. Grain is considered unlit for sale as fe when the ergot sclerotia content exceeds 0.3%. 

The oat grain very closely resembles a kernel of wheat in structure. Unlike wheat, however, the nutritious bran and germ are not removed in the normal processing because oats are not refined. The most important nutritional advantage of oats is the soluble fiber which helps to lower the cholesterol in the blood. Oat bran is a major source of this fiber. 

Otlewska A, Walczak P, Kalinowska H, Dybka K, Oltuszak-WalczakE, Czyzowska A, Rygala A (2012) 1-Lactic acid production from rye and oat grains. New Biotechnol 29(Suppl) S174. doi 10.1016/j.nbt.2012.08.485... 

Average values, in mg. Ca per 100 gm. fresh edible tissue, are asparagus, 28 j beetroot, 21 cabbage leaf, 119 lettuce leaf, 35 onion bulb, 42 potato tuber, 11 oat grain, 117 barley grain, 86 wheat grain, 90. 

Doehlert, D.C., McMuUen, M.S., and Jannink, J.-L. 2006. Oat grain/groat size ratios A physical basis for test weight. Cereal Chem. 83( 1) 114—118. 

---