| Our country is a big country of corn production. In industry, we mainly use thestarch of corn endosperm not corn protein and in the factory, we sell by-productssuch as "yellow powder" and "plumule cake", which are rich in protein, as feed.Not only does it cause low economic performance of the enterprise, but also is agreat waste of protein source which is not rich in our country.Produces corn starch, at the same time, we get the yellow water of cornprotein, then we can get the yellow powder which is rich in protein, that is cornprotein powder, after the further processing. It contains more than 60% of protein,some are 70%, and others are 20% of starch and about 13% of fiber. Corn proteinpowder is lack of lysine and tryptophan which are necessary for human andbiological titer is lower, so before we sell it as feed protein with low value. Theprotein contained in corn protein powder is mainly zein. In recent years, foreignand domestic researchers pay attention to using and developing zein. Although itsbiological titer is low, it has some properties that other proteins do not have. If wecan reasonably use it, we will improve the economic performance greatly.In this essay, we see corn embryo produced from corn starch, as material,search for a method of producing corn embryo protein – the efficient, high-qualityprotein and try to apply it to food production. Now, we get an good effect.Eatable film is the developing direction of food packing in future. Zein isgood material of forming eatable film, which is heat-resistant, water-resistant andoil-resistant. The development and application of zein film must put thedevelopment of eatable film forward. In this essay, we synthesize the advancedtechnologies of extracting and reclaiming zein, bring our own thought into it andsearch for a new technology of producing edible zein, which is well dissolving andconsuming less solvent. We believe this technology is an advanced technology isthis field now.1. In this essay, we search and determine the making technique of cornembryo protein. The material is embryo cake removing the oil of corn embryo. Thematerial is cheap and easily got and the product has high additional value. For theextraction technique, the best parameter is a PH of 9..5;the density of flux is 12%;time is an hour and the temperature is 60℃. In this technique, the highestproductivity can reach to 44.1% and corn embryo protein contains 93.1% ofprotein(wet stuff).The test verifies: the maize embryo albumen has comparatively fine functionand property . Comparing Maize embryo albumen with soybean separate albumen,the maize embryo albumen has relatively low solubility. As for water-holding andemulsification stability,both albumen have small difference. But the maize embryoalbumen's oil-holding is slightly superior to the soybean albumen.Maize embryo albumen's application test of the bologna sausage verify:it canobviously improve the producing rate of the products, and it have not been notablyinfluenced on the flavor and storage stability of the products.2. Zein is fine raw materials of forming edible membrane. This kind ofmembrane has good heat resistance, wet resistance and oil resistance . Zeinmembrane's development and application is sure to promote edible membrane'sdevelopment. This text synthesizes the advanced technology of drawing andretrieving zein both at home and abroad, and incorporate one's own thought ,explore new technology of applying to produce edible zein. This kind of producthas fine solubility, and it consumes little solvent .I believe it is comparativelyadvanced technology at present in this field.(1) This thesis confirms one new technological process of producing zein.meet picture 2-2, its craft characteristic is: saving solvents ,tall purity of theproducts ,good solubility , reducing labour intensity. The best condition ofextracting in the craft is: the liquid is firm than 14:1, PH 9.0, temperature is 50 ℃,time is 2.0 hours. The best condition of retrieving is: 1 NaCl solution, by 1: Lvolume ratio with alcohol dissolve albumen draw liquid mix. This craft product'shigh yield rate can reach 45.17%,The protein's content is up to 92.76% in theproduct (wet stuff ).(2) Zein can form better performance edible membrane. pH, zein's density andethanol's density are main factors of influencing membrane's performance. Themembrane condition is as follows in the optimization of each performance.a. pH is 8.0~8.8, when the ethanol's density is 90~95%, membrane'sdiaphaneity is high.b. When zein's density is 25~30%, pH is 8.4~9.2, membrane's intension ofdraw-resistence is strong.c. Water vapor permeabilit resoponse surface indicate: in the diagonaldirection(from pH 8.4, ethanol's density 75% to pH 6.4, ethanol's density 85%),membrane is the most water-fast.d. In the middle level(pH 8.0~8.8), membrane's oil-resistence is good.(3) Zein can play an anti-oxidant role to coating parcel almond . To pass ,oxidize , worth the level keeps the same with the levels of the 4th day of ones thatare not deployed 16 day almond after the coating. So it can improve qualityguarantee period.This text is on the premise of deep processing of comprehensive maize,extracting zein, and applying it to edible membrane, and making qualitative andquantitative research on the performance of membrane and the forming factor'srelation at the same time.I expect this thesis can promote the research on this fieldand the application and popularization of edible membranes.
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