Modified chromogenic alpha-amylase assay for sprouted wheat

Area of Science:

• Agricultural Science
• Biochemistry
• Food Science

Background:

• Alpha-amylase activity is a key indicator of sprout damage in wheat.
• Accurate measurement of alpha-amylase is crucial for wheat quality assessment, particularly for processed products.
• Existing assays may lack the sensitivity required for certain wheat varieties and applications.

Purpose of the Study:

• To enhance the sensitivity of an existing alpha-amylase assay for sprouted wheat.
• To optimize assay conditions for improved detection of low alpha-amylase levels.
• To extend the applicability of the assay to wheat used in Japanese noodle and sponge cake manufacturing.

Main Methods:

• Optimized the assay buffer to pH 6.20.
• Utilized Cibacron-Blue dyed amylose as the substrate.
• Conducted the assay at an elevated temperature of 60 degrees C.

Main Results:

• The modified assay demonstrated increased sensitivity compared to previous methods.
• Measurable alpha-amylase levels were detected in the range of 3--30 millidextrinizing units (mDU).
• This represents a lower detection range than the 10--90 mDU previously reported for bread wheats.

Conclusions:

• The optimized alpha-amylase assay offers superior sensitivity for sprouted wheat analysis.
• The enhanced test is valuable for assessing sprout damage in wheat intended for Japanese noodles and sponge cakes.
• This improvement aids in ensuring wheat quality for specific food manufacturing processes.