Wheat and Flour Testing Methods - WHEATFLOURBOOK.ORG

Extensigraph
Method
Preparation
1. A 300-gram flour sample on a 14 percent moisture basis
is combined with a salt solution and mixed in the farinograph
to form a dough.
2. After the dough is rested for 5 minutes, it is mixed to
maximum consistency (peak time).
Analyses
1. A 150-gram sample of prepared dough is placed on the
extensigraph rounder and shaped into a ball.
2. The ball of dough is removed from the rounder and
shaped into a cylinder.
3. The dough cylinder is placed into the extensigraph
dough cradle, secured with pins, and rested for
45 minutes in a controlled environment.
4. A hook is drawn through the dough, stretching it downwards
until it breaks.
5. The extensigraph records a curve on graph paper as the
test is run.
6. The same dough is shaped and stretched two more
times, at 90 minutes and at 135 minutes.
Results
• The extensigraph determines the resistance and extensibility
of a dough by measuring the force required to
stretch the dough with a hook until it breaks.
• Extensigraph results include resistance to extension,
extensibility, and area under the curve.
• Resistance to extension is a measure of dough strength.
A higher resistance to extension requires more force to
stretch the dough.
• Extensibility indicates the amount of elasticity in the
dough and its ability to stretch without breaking.
• Extensigraph curves are described on pages 48.
n Visco-elastic recorder
Dough stretched by the extensigraph hook.
n Measures dough extensibility
and resistance to extension
Why is this important?
Results from the extensigraph test are useful in determining
the gluten strength and bread-making characteristics of flour.
The effect of fermentation time and additives on dough
performance can also be evaluated.
Wheat and Flour Testing Methods: A Guide to Understanding Wheat and Flour Quality: Version 2