Amazein™ is the trade name of a highly functional protein produced from raw whole corn (maize) by Prairie Gold Inc. The protein is “zein” (commonly pronounced “zayne” to rhyme with rain or cane), which is one of four different classes of proteins in corn. Zein refers to a family of alcohol-soluble proteins known historically as prolamines. Prolamines in corn (maize) are called zein, while they are known as hordein in barley, kafirin in sorghum and gliadin in wheat. Commercial zein is not a single protein, but a mixture of individual zein fractions. Individual zein fractions in a commercial product depend on the extraction conditions, such as the type of alcohol (ethanol vs. isopropanol), the concentration of alcohol (typically 50-95% v/v ethanol or isopropanol in water), temperature, reagents added (such as alkali or reducing agents) and the raw material (native corn kernels or corn processing by-products), as well as the methods of purification, concentration and drying. There has been some confusion in the scientific literature about the nomenclature for individual zeins since McKinney (1958) first defined zein components based on solubility: α-zein is soluble in 95% ethanol or 85% isopropanol, while β-zein is insoluble in 95% ethanol but soluble in 60% ethanol. Figure 1 compares several nomenclatures mentioned in the literature. |
Esen’s method is now widely accepted and is used by Prairie Gold with Amazein™. In the Esen system, there are four major fractions:
WHAT MAKES AMAZEIN™ DIFFERENT? Amazein™ is manufactured using the patented COPE process developed at the University of Illinois and licensed exclusively by Prairie Gold. The main factors that make Amazein™ unique and superior are:
There are a number of other zein fractions that could exist in native corn. For example, dimers and possible trimers of α-zein have been identified in commercial products and in Amazein™ by electrophoresis. Figure 2 shows electrophoretic patterns of Amazein™ of various protein contents and commercial samples of zein from Freeman Company (USA) and Showa Sangyo (Japan). The protein contents are expressed as N x 6.25 on a dry basis. The major fractions (α-zein, dimers and trimers) are visible but the β- and γ-zeins are not easy to see in gels, although they are sometimes visible in the scans of the gels. Figures 3 and 4 show scans of typical gels of Amazein™ and commercial samples. Figures 5-7 show additional evidence for the presence of multiple fractions of zein in corn extract, Amazein™ and a Freeman zein by MALDI-MS (matrix-assisted laser desorption ionization – mass spectroscopy). The lower molecular weight fractions of zein are easier to identify by this technique. Interestingly, the β-zein (17-19K) appears to be missing in Freeman products (Figure 7). |
Certain processing methods, e.g., addition of reducing agents, could break disulfide bonds and eliminate or reduce the proportion of some of the zein fractions. Different solvents can change the relative proportions of the zeins being co-extracted. In addition, individual zeins vary in composition and differ in their amino acid sequences and surface charges based on corn genotypes, location of protein bodies in the kernel and age of the kernel. The composition of the zein products, in terms of the relative proportions of zein fractions, could have an effect on the functional properties of zein and its utilization. Amazein™, the only zein product extracted from raw corn, will have a protein profile that reflects the corn that was used as the raw material and in all likelihood will contain many of the zein fractions present in corn in varying proportions. This should be taken into account when using Amazein™ in certain applications. |
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For further information about Amazein™, contact Prairie Gold, Inc. 501 S. Towanda Barnes Rd Email: [email protected] Phone: 1-309-661-4280 |