Cereal Chem 56:352 - 355.  |  VIEW ARTICLE
Characteristics of Sunflower Seed and Meal.

P. J. Wan, G. W. Baker, S. P. Clark, and S. W. Matlock. Copyright 1979 by the American Association of Cereal Chemists, Inc. 

Comparison of chemical compositions of confectionary and high oil variety sunflower seeds indicated that their kernels contain similar oil, protein, crude fiber, and ash contents. The only obvious differences between the two types of seed are the bulk density of seed, the proportion and thickness of hulls, and the degree of black coloration on the surface of hulls. Whole confectionary seeds are lower in oil because they have a higher fraction of hull. The thin and dark hulls of high oil seeds create difficulties in processing food grade sunflower protein products. In particular, the dark specks coming from the surface of hulls may make sunflower seed flour nearly black when it is wet. The maximum tolerable level of unhulled seed in the kernel fraction was established by observing flour samples with known proportions of unhulled seed and measuring their color with a Hunterlab Color Difference Meter. The tolerable levels are 3 and 5%, respectively, for high oil and confectionary varieties. This article proposes a method for estimating the amount of hull in kernel-hull mixtures or of crude fiber in meal fractions from seed of known composition, based on the nitrogen content of the dry defatted meal.