Zein
From Wikipedia, the free encyclopedia
Zein is a class of prolamine protein found in maize. It is usually manufactured as a powder from corn gluten meal.
Zein is one of the most well understood plant proteins[1] and has a variety of industrial and food uses.[2][3] Historically it has been used in the manufacture of a wide variety of commercial products including coatings for paper cups, soda bottle cap linings, clothing fabric,[4] buttons, adhesives, coatings and binders. The dominant historical use of zein was in the textile fibers market where it was produced under the name "Vicara".[2][5] With the development of synthetic alternatives, the use of zein in this market eventually disappeared. By utilizing electrospinning, zein fibers have again been produced in the lab where additional research will be performed to re-enter the fiber market.[6][7] Pure zein is clear, odorless, tasteless, hard, water-insoluble, and edible, making it invaluable in processed foods and pharmaceuticals, in competition with insect shellac. It is now used as a coating for candy, nuts, fruit, pills, and other encapsulated foods and drugs. In the United States it may be labeled as "confectioner's glaze" (which may also refer to shellac-based glazes) and used as a coating on bakery products[8]or as "vegetable protein." It is classified as GRAS (Generally Recognized as Safe) by the U.S. Food and Drug Administration.
Zein can be further processed into resins and other bioplastic polymers which can be extruded or rolled into a variety of plastic products.[9][10] With increasing environmental concerns about synthetic coatings (such as PFOA) and the currently higher prices of hydrocarbon based petrochemicals, there is increased focus on zein as a raw material for a variety of non-toxic and renewable polymer applications, particularly in paper industry applications.[11][12] Other reasons for a renewed interest in zein include concern about the landfill costs of plastics and consumer interest in natural substances. There are also a number of potential new food industry applications.
Researchers at the University of Illinois at Urbana-Champaign and at Wm. Wrigley Jr. Company have recently been studying the possibility of using zein to replace some of the gum base in chewing gum.[13] They are also studying medical applications such as using the zein molecule to "carry biocompounds to targeted sites in the human body".[14] There are a number of potential food safety applications that may be possible for zein-based packaging according to several researchers. A military contractor is researching the use of zein to protect MRE food packages.[15] Other packaging/food safety applications that have been researched include frozen foods,[16] ready-to-eat chicken,[17]and cheese and liquid eggs.[18] Food researchers in Japan have noted the ability of the zein molecule to act as a water barrier.[19]
While there are numerous existing and potential uses for zein, the main barrier to greater commercial success has been its historic high cost until recently. Some believe the solution is to extract zein as a byproduct in the manufacturing process for ethanol[20] or in new off-shore manufacture.
[edit] References
- ^ Momany, Frank A.; Sessa, David J.; Lawton, John C.; Selling, Gordon W.; Hamaker, Sharon A. H.; and Willett, Julious L. "Structural Characterization of A-Zein" December 27, 2005, American Chemical Society
- ^ a b Lawton, John W. "Zein: A History of Processing and Use", November 1, 2002, American Association of Cereal Chemists
- ^ Gennadios, Aristippos"Protein-Based Films and Coatings" 2002
- ^ Commission on Life Sciences "Biobased Industrial Products: Research and Commercialization Priorities" 2002.
- ^ Horst, W.P. Amer Dyestuff Rep Vol. 38, 335, 1949.
- ^ Miyoshi, T., Toyohara, H., Minematsu, H. "Preparation of ultrafine fibrous zein membranes via electrospinning", Polymer International Vol. 54, no. 8, 2005.
- ^ Selling, G., Biswas, A., Patel, A., Walls, D., Dunlap, C., Wei, Y. "Impact of Solvent on Electrospinning of Zein and Analysis of Resulting Fibers", Macromolecular Chemistry and Physics Vol. 208, no. 9, 2007.
- ^ Kobs, Lisa "Shining Up Appearances", Food Product Design.
- ^ Lee, Richard "Multiple-use Corn zein-based Biodegradable Resins, Sheets, and Films are an attractive alternative to plastic", University of Illinois at Urbana-Champaign.
- ^ Lawton Jr., J.W. "Plasticizers for Zein:their Effect on Tensile Properties and Water Absorption of Zein Films" January 12, 2004, Cereal Chemistry.
- ^ Jabar, Anthony Jr; Bilodeau, Michael A.; Neivandt, David J.; Spender, Jonathan "Barrier Compositions and Articles Produced with the Compositions", December 29, 2005, United States Patent (pending)
- ^ Parris, Nicholas; Sykes, Marguerite; Dickey, Leland C.; Wiles, Jack L.; Urbanik, Thomas J.; Cooke, Peter H. "Recyclable zein-coated kraft paper", Progress in paper recycling Vol. 11, no. 3 May 2002.
- ^ McGowan B.A., Padua G.W., and Lee S-Y. "Formulation of Corn Zein Chewing Gum and Evaluation of Sensory Properties by the Time-Intensity Method", September, 2005, Journal of Food Science.
- ^ Picklesimer, Phyllis. "Nanotechnologist Plans to Build Things with Bricklike Corn Molecules," University of Illinois at Urbana-Champaign.
- ^ Bertrand, Kate, "Military packages put technology to the test," September 2005
- ^ Padua, Graciela W., Rakotonirainy, Andrianaivo, and Wang, Qin "Zein-Based Biodegradable Packaging for Frozen Foods",University of Illinois at Urbana-Champaign
- ^ Janes M.E.; Kooshesh S.; Johnson M.G. "Control of Listeria monocytogenes on the Surface of Refrigerated, Ready-to-eat Chicken Coated with Edible Zein Film" September, 2002, Journal of Food Science.
- ^ Dawson, Paul "Packaging Films Fight Bacteria and Help the Environment" Clemson University
- ^ Qiangxian Wu, Hiroshi Sakabe and Seiichiro Isobe "Studies on the toughness and water resistance of zein-based polymers by modification" June, 2003, National Food Research Institute, Japan.
- ^ Core, Jim. "Corn Protein Could Reduce Ethanol Production Costs," April 15, 2002, United States Department of Agriculture Agricultural Research Service.
[edit] External links
- Illinois Corn: Corn Zein-Based product technology
- Oregon State University Food Resource: Zein
- Zein Protein Products: Non-GMO Corn Zein Supplier
- Freeman Industries: Corn Zein Supplier
