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Maize corn steep water is generated when the production of starch wet organic waste, which contains 3-4% of the protein. Corn steep water protein with enhanced immunity, antioxidant activity and other physiological characteristics, is not yet fully exploited protein resources. If you can soak corn protein extracted, not only can improve the economic benefit to solve environmental pollution problems, but also can develop new protein resources. In this paper, soaked in water, crude protein corn as raw material, purified by ammonium sulfate precipitation, a preliminary study of its nature. By their nature, study, alcohol washing and alkali-soluble and acid precipitation are two ways to further purification of crude protein corn steep water conditions and then study the corn steep water purified functional properties of protein concentrates, and finally add it to the ham, study its content on the ham texture characteristics. With 40% saturated ammonium sulfate precipitation, separation and purification of crude protein corn steep water, the purity of 84.57% (w / w), corn steep water reaches the level of protein concentrate, after desalting by dialysis, and the nature of the basic composition. The results showed that: corn steep water contains more protein hydrophobic amino acids and acidic amino acids, and the highest proline; the same time, increasing the content of hydrophobic amino acid to have a good thermal stability; SDS-PAGE electrophoresis and Sephadex-G50 gel chromatography showed that corn steep water protein concentrate mainly in the 10000 Da molecular weight less. Washed with ethanol alcohol and alkali-soluble and acid precipitation on corn steep water two methods for purification of crude protein. The experimental results showed that: alcohol cleaning method does not apply to corn steep water purifying crude protein; experimental range, alkali solution and acid purification of crude protein corn steep water suitable conditions: temperature 25 ℃, alkali-soluble phase pH 12, extraction time 20 min, solid-liquid ratio (W: V) l: 35, acid precipitation phase pH 5.5. After the corn steep water purified protein yield was 70.06%, 91.84% purity can be achieved. Therefore, the choice of alkali solution and acid purification of crude protein corn steep water. Isolated soy protein as control, the corn steep water functional properties of protein concentrates were evaluated, the results showed that: CSWPC emulsion stability, foaming and stability, oil resistance and gel-forming properties are superior to soy protein isolate; CSWPC at a NaCl concentration of 0.15 mol / L, temperature is 70 ℃, away from the isoelectric point of the alkaline environment with good solubility; its water holding capacity increases as the pH increases gradually, with the increase of temperature and NaCl concentration decreases, at 60 ℃, NaCl concentration of 0.15 mol / L, pH of 10, preferably water holding capacity; at a temperature of 80 ℃, protein concentration of 2% acidic environment CSWPC lower the viscosity. Add the ham corn steep water protein concentrate, make ham yield increased by 14.4%, and for ham color and texture characteristics have an effect. When the added amount of protein in the range of 0.5 to 1% within the appearance of intestinal ham body dry, no mucus, no damage, color uniform, dense and elastic.
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