Amylograph
An amylograph is a laboratory device from Brabender that can be used to determine the gelatinization properties of rye or wheat flours. Amylographs are used in the mill laboratory , in large bakeries and by baking agent manufacturers. Because of their high starch content, flours have the property of gelatinizing in the presence of water and heat. This is important for the formation of a crumb during the baking process . An amylograph is therefore used for dough rheological investigation.
Principle of the method
A flour-water suspension is heated and stirred continuously (1.5 ° C per minute) in the amylograph pot. With increasing temperature (from approx. 60 ° C for rye and approx. 70 ° C for wheat flours) the starch gelatinizes and the viscosity increases. The rising temperature is intended to simulate the temperature curve in an oven . The increasing torque between the rods of the pot and the stirrer is recorded in a curve (amylogram) - in earlier devices on recording paper, today in a computer program which also carries out the evaluation. The test is carried out in accordance with ICC Standard No. 126.
application
With the help of the amylogram:
- the temperature at the start of gelatinization
- the temperature in the gelatinization maximum
- the height of the gelatinization maximum
can be read.
Since the gelatinization depends not only on the amount of starch, but also on the activity of the α- amylases , the temperature during the gelatinization is a decisive factor. If the temperature at the gelatinisation maximum is too low, this means that the amylases still have enough time during the baking process to break down starch and prevent sufficient gelatinisation, as is the case, for example, with outgrowth . Thus, an amylogram also indirectly makes statements about the amylase activity. It is thus also possible to determine the type and dosage of enzyme or malt flour additives .
An acid amylogram (1.1 ml of 90% lactic acid added at the start of the experiment) can be used to test whether a rye flour would still be bakeable if it were made with sourdough .
Individual evidence
- ↑ Brabender product page
- ↑ List of ICC Standard Methods ( Memento of the original from August 15, 2010 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
- ^ Burghard Kirsch: Milling technology, materials science. Composition, study, evaluation and use of grain and grain products . 8th edition. Bayerischer Müllerbund, Munich 2016, ISBN 978-3-9812436-6-6 .
- ↑ Data sheet ( Memento from January 29, 2016 in the Internet Archive ) (PDF; 392 kB)
