Location: Functional Foods ResearchTitle: Practical application of amino acids as natural antioxidants for frying
Submitted to: American Oil Chemists' Society Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 11/3/2018
Publication Date: 5/8/2019
Citation: Hwang, H., Moser, J.K., Doll, K.M., Gadgil, M., Liu, S.X. 2019. Practical application of amino acids as natural antioxidants for frying [abstract]. American Oil Chemists' Society Annual Meeting & Expo. Paper No. 4B-1025.
Technical Abstract: Our previous study showed that amino acids were excellent natural antioxidants for frying oils. We conducted further studies on their activities, especially, for their practical application. Antioxidant activities of amino acids were compared to the synthetic antioxidant, tert-butylhydroquinone (TBHQ), and leading commercial natural antioxidants including tocopherols and rosemary extract in soybean oil at 180 ºC. Sensory impact and labeling will also be discussed. Factors affecting their activities such as lipophilicity, basicity, effect of side chains and other functional groups, and chelation of metals will be discussed. We found that, in general, higher lipophilicity, higher basicity, and longer alkyl chain increased the antioxidant activity of an amino acids, although there were some exceptions. The chelation of metals by an amino acid and antioxidant activity of secondary products produced by reactions between an amino acid and oxidation products, which were known to be important factors for its activity, did not play critical roles at frying temperatures. Peptides and protein hydrolysates have drawn interest as potential natural antioxidants for frying. We compared their antioxidant activities with amino acids. Although protein hydrolysates and dipeptides also showed strong antioxidant activity in soybean oil at 180 ºC, their activities were not as strong as some single amino acids.