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ARS Home » Midwest Area » Peoria, Illinois » National Center for Agricultural Utilization Research » Functional Foods Research » Research » Publications at this Location » Publication #369561

Research Project: Improving Quality, Stability, and Functionality of Oils and Bioactive Lipids

Location: Functional Foods Research

Title: Analysis of polymers formed during frying french fries in soybean oil

item Hwang, Hong-Sik
item BALL, JAMES - Ford Motor Company
item Doll, Kenneth - Ken
item Vermillion, Karl

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 7/15/2020
Publication Date: 7/15/2020
Citation: Hwang, H., Ball, J.C., Doll, K.M., Vermillion, K. 2020. Analysis of polymers formed during frying french fries in soybean oil. Meeting Abstract. IFT Annual Meeting & Food Expo 2020. July 12-15, 2020, Chicago, IL.

Interpretive Summary:

Technical Abstract: Polymers are major oxidation products remained in frying oil, which are known to be associated with adverse health effects. Frying oil containing 25% total polar compounds, the typical regulatory limit, may contain about 10% polymers. Therefore, it is important to understand chemical bonds forming polymers for prevention of polymerization as well as for understanding toxicity of oxidized oil. Previously our research group reported that no noticeable Diels-Alder reaction products were formed in soybean oil (SBO) oxidized at frying temperatures. This study aimed to identify chemical bonds forming polymers during frying. SBO oxidized by frying and heating showed significantly increased ester value evidencing new ester bonds were formed during oxidation. New ester carbonyl carbon signals were also observed in the ^13^C NMR spectrum of oxidized oil. An approximate calculation showed that ester bonds are partly responsible for polymerization of oil and there should be other chemicals bonds forming polymers. The NMR study of oxidized SBO also identified several new oxidation products, for examples, an alcohol showing ^1^H NMR signal at 5.07 ppm and ^13^C NMR signal at 72.2 ppm. Although further studies are needed to verify some other chemical bonds forming polymers, this study evidenced that ester bonds are responsible for polymerization of frying oil. There are numerous oxidation products during frying and identification of these substances is very challenging. This study identified several NMR signals of alcohols formed during oxidation of SBO.