Dehulling cottonseed and separating kernels and hulls: Comparison of several varieties of seed

The proteinaceous components of cottonseed can be converted into several different forms for use in human food. All of them require nearly complete separation of kernels and hulls. In research on improving separation processes, eight multiton lots of cottonseed were processed through pilot size commercial-type dehulling and kernel-hull separating machinery. The machinery was operated to produce the cleanest separations possible. Each lot of seed was from a different variety of cotton. For six of the lots, seed were delinted to 2 levels of ca. 7.0 and 2.5% residual linters; and separate dehulling runs were made on seed of each level. Weak hulled seeds were the only lots showing any important differences in dehulling characteristics. They produced higher yields of coarse kernels than the other lots. In terms of nearly pure kernels, good results were obtained with all lots. Yields of kernels averaging 90% of the total kernels from each variety were concentrated into a product which contained less than 1.0% hulls. These products could be converted into meals of more than 55% protein and less than 3% crude fiber. With the addition of a specific gravity separator to the process, loose hulls in coarse kernels can be reduced to nearly zero. One of seven papers presented at the symposium, “Processing Methods for Oilseeds,” AOCS Spring Meeting, New Orleans, April 1973.