Effects of oat lipids on great meal pasting properties

The Australian oat cultivar Yarran is unacceptable for human food use due t o poor flavour, colour and texture. It has a high lipid content which conta ins a high proportion of oleic acid. It was compared with an acceptable var iety, Mortlock, which has a characteristically lower lipid content with a l ower proportion of oleic acid, to study the effect of lipid content on past ing properties of the oat meal. The lipids of both varieties were extracted with petroleum ether and were added back into the defatted meals in sequen tial amounts. These meals were then tested for viscosity parameters. Both l ipid content and composition significantly influenced the meal pasting prop erties. The peak viscosity and time to peak viscosity were negatively corre lated with lipid content whereas setback and pasting temperature increased with increased lipid content. The lipids from Yarran and Mortlock had diffe rent effects on the pasting properties. The Mortlock lipid increased the fi nal viscosity (FV) of the defatted meal of Yarran but showed little effect on the FV of its own cultivar. However, the results indicated that the lipi d content/composition, although affecting pasting characteristics substanti ally, were not as important as other meal properties in controlling accepta bility for human food use. (C) 1999 Society of Chemical Industry.