Biochemisch-technologische Studien über die Naßverarbeitung von Mais 5. Mitteilung. Untersuchung des amylolytischen Enzymsystems des Maises

✍ Scribed by Dr. G. Wahl

• Publisher: John Wiley and Sons
• Year: 1971
• Tongue: English
• Weight: 408 KB
• Volume: 23
• Category: Article
• ISSN: 0038-9056
• DOI: 10.1002/star.19710230304

✦ Synopsis

Abstract

Biochemical‐Technological Studies on Wet‐Processing of Maize. Part 5. Examination of the Amylolytic Enzyme System of Maize.

1. Amylolytic activity of the enzyme preparations isolated from the ungerminated maize is limited to the pH‐range from 3.0 to 8.4. Activity reaches its optimum at a pH of 5.2.

2. With starch dispersion the temperature optimum lies in the range of 50 °C, with non‐gelatinized maize starch around 60 °C.

3. A rapid decrease of stability, noticed at 20 °C and pH‐values between 3.5 and 4.7 is attributed to the proteolysis of the enzyme protein. At 50 °C the amylolytic enzymes in aqueous solutions are instable over the entire pH‐range.

4. Complete inactivation is reached by means of SH‐inhibitors (10^−2^ M iodine acetic acid, 3·10^−3^ M p‐chlorine mercury benzoic acid) respectively 10^−4^ M mercury dichloride.

5. SO~‐2~‐contents of 0.01% increase activity distinctly, at 0.03% complete inactivation takes place because of the pH‐shift to 3.4. With the influence of sulfite an activation is also found to take place at higher amounts.