D/R Dough Inflation System
Bakers have always characterised dough by hand kneading and stretching to assess its quality, and know that baking performance is related to these rheological properties. Such a simple test indicates the type of measurements that are required to predict baking performance. Bread making is a complex process involving mixing, dividing, moulding, sheeting, proofing to final baking, each of which have a characteristic time scale, strain and strain rate. As the rheological behaviour of dough is non-linear with strain, measurements must be made under conditions of strain and strain rate similar to those encountered in baking.
The D/R Dough Inflation System measures dough extensional rheology under conditions of strain similar to those of baking expansion. This is achieved by inflating a sheet of dough by volume displacement of air using a piston driven by a Stable Micro Systems TA.XTplus Texture Analyser. Pressure during inflation is measured by a pressure transducer and the volume of the inflating dough sheet is calculated from the displacement of the piston.
The D/R Dough Inflation System enables the rheological properties of both dough and gluten to be measured during biaxial stretching, which is the relevant deformation in the cell wall material surrounding an expanding gas bubble during proof and baking. The system together with dedicated software, combines ease of use with automatic data collection and rapid project based data analysis.
The procedure requires minimum handling of the dough when preparing samples – there is no contact of the sample when transferring to the D/R Dough Inflation System. This sophisticated system is a very comprehensive test tool for research, Q/C, production or process monitoring. The test, display of the result and calculation of index values are fully automatic.
The software provides users of the TA.XTplus or TA.HDplus Texture Analyser, in conjunction with the D/R Dough Inflation System, with real-time graphical display, and analysis of the test. Tools are provided to make measurements, such as drum distance, pressure ratios, areas, volume change and deformation energy between two points as well as simple spot values.
The software has built in macro and spreadsheet facilities to aid automated data collection and analysis. The spreadsheets support a range of mathematical functions that enable results to be derived from the basic data. Charts are easily created to present spreadsheet results in a more convenient format.
Graphs, Charts and Spreadsheet data are all compatible with other Windowstm applications via the clipboard to create sophisticated presentations with other programs.
System 2 Features
Increased Inflation Volume
Whilst modifying the composition of cereals, users have expanded their range of products and functional ingredients have provided substantially wider rheological properties, increased extensional behaviour being one such example. This has led to the requirement for higher inflation volumes for the measurement of burst points – this has now been increased to 2.3 litres.
Temperature Controlled Testing
In the process of design modification the ability to inflate dough up to temperatures of 60oC has been incorporated by the addition of a customised temperature chamber. This not only provides the desired inflation temperature for dough but also houses samples during their pre-test equilibration period.
New Sample Preparation Features
More flexible sample rolling
Recognising that rolling in one direction causes linearising of dough proteins, Stable Micro Systems have modified the sample preparation platform to allow for bidirectional rolling.
Smaller sample sizes
For research and wheat breeders, flour is commonly in short supply. The addition of smaller testing dimensions provide the ideal solution allowing sample preparation and testing of 3 samples from 16.5g of dough (approximately 10g flour).