الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
In this work three types of modified starch, thin boiling starch, oxidized starch and starch phosphate were prepared.
Three procedures No.(1-1, 1-2, 1-3) were carried out by using hydrochloric Acid, phosphoric acid and mixture of hydrochloric and phosphoric acid to prepare three samples of thin boiling starch procedure No. 2 was conducted by using sodium dihydrogen phosphate to prepare starch phosphate.
Three different runs No.(3-1, 3-2 and 3-2) were performed by using hydrogen peroxide and sodium hypochlorite dry methode to prepare three samples of oxidized starch.
The solubility and swelling power of thin boiling starch,
oxidized starch and starch phosphate were determined at 90°C, 50°C, and 20°C. And at 90°C, 70°C, 50°C and 20°C for viscosity. The carbonyl and carboxyl content of oxidized starch samble were determined in oxidized starch samble the results showed that the solubility of thin boiling starch was very high (78 —
94%) especially at 90°C. By comparison, these values with the solubility of native corn starch (12.7%)et 90°C.
The swelling power of thin boiling starch at 90°C reached 32-37, and this value was higher than the swelling power of native corn starch (11.3).
The viscocity of thin boiling starch samples at different temperatures of measurenients are very low with comparison the viscosity of native corn starch. The viscosity of thin boiling
starch at 50°C ranging from 28-48 C.P.S in contrast the viscocity of native corn starch at 50°C equal 9220 C.P.S.
2- the solubility of starch phosphate at 90°C was very high (97.8%)the swelling power was (433,82.68 and 42.59) at 90°C, 50°C and 20°C. These values was very high by comparison with
the swelling power of native starch, thin boiling starch and oxidized starch.
The apparent viscosity of starch phosphate at 90°C was 322 C.P.S. the viscosity was increased by decease the temperature of viscosity determination.
3- the solubility at 20°C and 50°C of the oxidized starch prepared from procedure(3-1) and (3-2) was slight increased than the native starch.’ The solubility at 90°C was high value (55 and 60%) in contrast With oxidized starch from procedure (3-3) the
solubility at 20°C,, 50°C and 90°C was high value (19.3, 28.7 and 91%).
The swelling power of the oxidized starch samples at
20°C and 50°C was unchanged approximatly than the native
starch the sweling power at 90°C was (20.8, 21.3 and 30.4).. these values was higher than the swelling power of native starch.
The apparent viscocity of oxidized starch sambles 3-1, 3-2, and 3-3 was 76.7%, 113 and 14.1 C.P.S at 90°C respectively and these values were very low with comparison the apparent viscocity of native corn starch. the viscocity of oxidized starch was increased by decreasing the temperature of viscosity.
Determination the carbonyl content of oxidized starch preoared by hydrogen proxidc was 2.8 and 2.6 where as carboxyl content remained low (0.4 and 0.5) when the oxidation was carried out by sodium hyboehlorite dry methods (prosedure 3-3) the carboxyl content was increased to 1.2% and the carbonyl content was decreased to 0.5%.
Thin boiling starch and oxidized starch still by birefringence where as starch phosphate lost their birefringence .