rotary viscometer / for starch / for flour / gelatinization
for starch, for flour, gelatinization
Micro Visco-Amylo-Graph for measuring the gelatinization properties of starches and flours
What does it measure?
The MVAG measures the gelatinization properties of starch and starch containing products. It also tests the viscosity of liquids, suspensions, and pasty products and, with flours, for determining the enzyme activity.
Why is this important?
- The baking properties of flour depend on the starch gelatinization and on the enzyme activity (α-amylase) in the flour.
- Sprouting in wheat, indicated by high enzyme activity, produces sticky dough and causes problems during processing and results in products with poor color and weak texture.
- Flour supplied from the mill can be checked if it meets the specifications forthe given application.
How is the test performed?
- A flour sample is combined with distilled water and mixed to a slurry, heated with a constant heating rate up to 7.5°C / min within a rotating bowl
- The slurry becomes a paste as the starch granules swell.
- Depending on the viscosity of the suspension, a measuring sensor reaching into the bowl is deflected.
- The deflection is measured as viscosity over time, i. e. vs. temperature, and recorded on-line.
The evaluation shows time, temperature and torque for:
- Beginning of viscosity rise
- Maximum viscosity
- Start of holding and cooling period
- End of cooling and final holding period
What are the benefits?
- Combined benefits of two instruments (Amylograph and Viscograph)
- Time-saving by getting fast and reliable results
- Material-saving thanks to small sample sizes
- Versatility in terms of manifold materials to be applied
- Temperature measurement inside the sample