Properties of Oat Starch

Oatrim can be used in cheeses as a fat replacer.12 Other possible applications are in ice cream and frozen desserts, milk shakes, hot chocolate, instant-type breakfast drinks, cereals, salad dressings, soups, sauces and gravies. Oat starch in combination with oat hydrolysate or with xanthan gum has been used for thickening of sweet and sour sauces.18 

Cationic oat starch was used to improve the dry strength of paper handsheets and found to be comparable to wheat starch in functionality.14 Oat starch might possibly be a replacement for rice starch in pharmaceutical applications.19 Oat flour has been used in adhesive preparations.19 

Even a very mild acid-catalyzed hydrolysis (0.5 hour with 1M HC1 at 40°C), followed by heating at 95°C, induced considerable changes in the oat starch granule, viz., a breaking down of the granule structure and formation of a continuous phase of amylopectin. 13The tendency for aggregation decreased when oat starch was annealed.15 

The chemical composition of isolated oat starch is given in Table 15.1. When an oat-flour slurry is centrifuged, the bottom layer is the prime starch. This starch can be purified with repeated washings, and a starch with a protein content of 0.44-0.6% and a lipid content of 0.67-1.11% (dry basis) can be obtained.10,27 The moisture, ash and nitrogen contents are similar to those of wheat, whereas the lipid content is higher than that of wheat, and the amylose content is lower.15 

Lysophosphatidylcholine makes up about 70% of the lipids present in oat starch.11 For AC Hill oat starch, free fatty acids dominated the neutral lipids (NL), lysophosphatidylcholine (a phospholipid, PL) and digalactosyldiglyceride (a galactolipid, GL).20 The predominant fatty acid was C18 2 in NL and C16 0 in PL and GL. Most of the phosphorus present in oat starch is present in lipids.8 There is a significant 

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Zhang, T. and Oates, C.G. 1999. Relationship between a-amylase degradation and physico-chemical properties of sweetpotato starches. Food Chem. 65, 157-163. 

Oat starch has properties that have captured industrial interest, but its use has been limited, largely because of difficulties in separation of the grain into starch, fiber and protein fractions.5... 

The physicochemical and chemical properties of fractionated components of starches from three oat cultivars have been compared with those of a hard red spring wheat starch and its fractions. On heating the starch gels, those from oats showed a greater reduction in viscosity than did those from wheat starch. 

Other organic fiber products which are mostly used in foods as dietary ballast additives are made from wheat, oats, tomato, apples, and citrus. Such dietary fibers are non-starch polysaccharides obtained from cell walls only, which can not be broken down by the digestive enzymes of the human organism and, therefore, constitute inert ballast materials. Color, taste, and odor relate to the fiber source. Unlike cereal brans or dietary fibers derived from, for example, sugar beets, which are often rejected by consumers because of their specific taste, wheat, oat, tomato, apple, and citrus fibers offer physiological properties that are much more readily accepted. 

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