A Study of Sunflower Oil
The advent of World War II cut off from the North American continent supplies of imported vegetable oils. This focused attention on a search for new plant sources, increased production from available sources and alteration of available vegetable oils by physical and chemical processes to meet industrial demands. This resulted in stimulation of the vegetable oil industry. The maintenance of this industry against competition from oil exporting countries requires production of superior oil products at costs which will not be excessive. In addition to production of oils in competition with imported oils, there has been an increased demand for modified oils specifically adapted for certain purposes, e.g., fast-drying oils. The modification of vegetable oils may be aided by a knowledge of the acids and glycerides that are present. Sunflower seed (Helianthus annus) is grown extensively in Russia, Argentine, China, Hungary and United States. Commercial production of sunflower seed in Canada has increased rapidly since 1941 as a war measure. The two main varieties are Sunrise and Mennonite, which are adapted to regions of a relatively long frost free period. Approximately 20,000 acres were seeded in Manitoba in1945, and two oil expeller mills have been built in Saskatchewan and Manitoba. The oil is an edible, semi-drying oil used extensively for Cooking and salad oils, shortenings and, to a limited extent, for paints and varnishes. Jamieson (63) gives the following fatty acid composition: oleic 33.4, linoleic 57.5, palmitic 3.5, stearic 2.9, arachidic 0.6 and lignoceric 0.4. Linolenic acid is not detected by chemical analyses. The present investigation Was undertaken to determine: (1) the relation of iodine value to fatty acid composition, (2) the glyceride structure by fractional crystallization, (3) if changes in the glyceride structure induced by physical and chemical treatment, such as molecular rearrangements, could be detected by fractional crystallization.