Articles
RSSExamination of Cottonseed Oil
December 7, 1999
Annual Project Report—Executive Summary
Sponsored by the Texas Food and Fibers Commission
Project: e-98-99-4
Project Title: Examination of Value Added Aspects of Cottonseed Oil and Evaluation of Cottonseed Oil as a Frying Oil
Investigator: C. Clay King
University/Department: Texas Woman's University / Department of Nutrition & Food Sciences
Project Scope:
Winterized cottonseed oil was directly compared with a commercially available, partially hydrogenated canola oil product (PHC), in order to evaluate its performance as a frying oil. French fries were fried daily over a ten-day period, and the quality of the fries was evaluated using sensory and objective evaluation. The quality of the oils was evaluated using various analytical tests.
Method of Research:
Winterized cottonseed oil and PHC were heated to 375ºF for six hours a day for ten days. Nine batches of French fries were fried daily in each oil. Samples of oil and French fries were analyzed on frying days 1, 4, 7, and 10. The oils were filtered on days 4 and 7. Fresh oil was added, to replace that lost by filtering or sampling, on days 1, 4, and 7. Sensory evaluation of the French fries was carried out using both a trained and a consumer panel. The fat content of the French fries was determined using the Soxhlet fat extraction method. Other analytical tests to monitor the quality of the frying oils throughout the frying period included measurement of fatty acid profiles, trans fatty acid content, free fatty acid content, color, viscosity, para-anisidine values, and polar contaminant materials.
Critical Findings:
Sensory evaluation of the French fries indicated that there was a significant difference between the products fried in the different oils. Panelists preferred French fries fried in winterized cottonseed oil to those fried in the canola product, particularly at the beginning of the frying period. As the oils aged, differences between the two oils became less obvious, although winterized cottonseed oil remained the oil of preference. Winterized cottonseed oil appeared to lose its initial flavor advantage, whereas the strong hydrogenated flavor of PHC appeared to be masked, probably due to development of other flavors during the frying process. The flavor of the French fries was the overriding factor in determining overall acceptability. Objective analysis indicated that there was little difference in stability and performance of the oils over the ten-day period. Winterized cottonseed oil contained little or no trans fatty acids (0.6%), whereas PHC contained 16% trans. The absence of trans fatty acids (known to be harmful) gives winterized cottonseed oil a nutritional advantage over partially hydrogenated canola oil.
Benefits:
Winterized cottonseed oil has both sensory and nutritional advantages, when compared with partially hydrogenated canola oil, in that it produces a milder, more pleasant French fry, and it contains little or no trans fatty acids. Winterized cottonseed oil could therefore be marketed as an all-purpose oil, suitable for use as both a salad oil and a frying oil. This would have a positive impact on the cottonseed oil industry.
