Microwave-assisted rapid modification of zein by octenyl succinic anhydride

• Published in: Cereal chemistry Vol. 82; no. 1; pp. 1 - 3
• Main Authors: Biswas, A, Sessa, D.J, Lawton, J.W, Gordon, S.H, Willett, J.L
• Format: Journal Article
• Language: English
• Published: St. Paul, MN The American Association of Cereal Chemists, Inc 2005; American Association of Cereal Chemists
• Subjects: absorption; Animal, plant, fungal and microbial proteins, edible seaweeds and food yeasts; biodegradable products; Biological and medical sciences; Cereal and baking product industries; chemical treatment; coatings; corn products; dicarboxylic acids; dimethylformamide; edible films; esterification; Food industries; food packaging; Fundamental and applied biological sciences. Psychology; hydrophobicity; infrared spectroscopy; mechanical properties; microwave treatment; nuclear magnetic resonance spectroscopy; octenyl succinic anhydride; water; zein; Chemical modification; Waterproofness; Upgrading; Plant protein; Mechanical properties; Zein; Hydrophobicity
• ISSN: 0009-0352; 1943-3638
• DOI: 10.1094/CC-82-0001

Corn is one of the most important food and industrial crops in the United States. Zein constitutes about half of the endosperm proteins in corn. Potential applications of zein include use in fibers, adhesives, inks, cosmetics, textiles, and chewing gum. Recently, attempts have been made to utilize zein for food coatings and biodegradable materials. The new applications of zein require it to be resistant to water. Thus, we are interested in new routes for chemical modification of zein (Biswas et al, unpublished). 2-Octenyl succinic anhydride (OSA) is extensively used in modifying food starches. Our objective was to take advantage of OSA hydophobicity, flexibility, and compatibility with nonpolar groups and incorporate OSA onto zein. This OSA-modified zein would possess the best of both OSA and zein. A zein solution in dimethyl formamide (DMF) was reacted with various levels of OSA to give modified zein. In a microwave reactor, the reactions proceeded tremendously fast and they were over in 5 min. The anhydride group of OSA reacted with the hydroxyl/amine group of zein to form ester/amide of zein. The reaction of OSA-modified zein was confirmed by proton nuclear magnetic resonance (NMR) and IR spectroscopy. The preliminary evaluation showed that zein and OSA-modified zein had comparable mechanical properties.