Off-campus UMass Amherst users: To download campus access dissertations, please use the following link to log into our proxy server with your UMass Amherst user name and password.

Non-UMass Amherst users: Please talk to your librarian about requesting this dissertation through interlibrary loan.

Dissertations that have an embargo placed on them will not be available to anyone until the embargo expires.



Access Type

Open Access Thesis

Document Type


Degree Program

Food Science

Degree Type

Master of Science (M.S.)

Year Degree Awarded


Month Degree Awarded



Lipid oxidation is a major challenge faced by the food industry since it causes loss of quality in lipid containing foods which results in a decrease of shelf life. In order to delay the oxidation in lipids, food industries make use of antioxidants such as EDTA (ethylene diamine tetraacetic acid), BHA (tbutyl-4-hydroxyanisole), BHT (t-butyl-4-hydroxytoluene), and TBHQ (tert-butyl-hydroxyquinone). However, these antioxidants are chemically synthesized and consumers desire simpler and cleaner labels without artificially synthesized antioxidants. Also, artificially synthesized antioxidants such as t-butyl-4-hydroxyanisole (BHA) can cause cancer in humans. Previous studies have shown that phospholipids such as phosphatidylethanolamine (PE) and phosphatidylcholine (PC) affect the activity of nonpolar antioxidants such as -tocopherol in bulk oils. PE when added to stripped soybean oil containing 100 M of -tocopherol was able to improve oxidative stability of the oil. However, PC decreased the activity of -tocopherol or had no effect. HPLC demonstrated that tocopherols were regenerated by PE which explains its synergism with - tocopherol. This study evaluated the effect of -tocopherol with varying levels of PE in stripped soybean oil. vi Additionally, antioxidant activity of -tocopherol has been shown to increase with increasing PE/PC ratio in lecithin. This study also examined the possibility of converting PC to PE in egg lecithin which will can be further used with -tocopherol. The enzyme phospholipase D was used for the conversion since it has been shown to have transphosphatidylation activity with phospholipids. The synergism of the modified lecithin with -tocopherol was analyzed in stripped soybean oil as well as in commercially refined oils. KEYWORDS: phospholipid, antioxidant, lipid oxidation, tocopherols, lecithin.


First Advisor

Eric Decker