Applications

The quality of dough-based products such as breads, pasta or noodles is highly dependent on the gluten quantity and quality of the flour. This means that everyone in the wheat chain, from breeder to baker, benefit from analyzing and controlling gluten properties with the Glutomatic® System.

Breeding

By measuring the functional properties of protein at an early stage - without having to extract flour - breeders can select the appropriate wheat classes for further breeding and refinement.

Grain Trading and Handling

The ease of use and the speed of the method enable the user to classify the incoming wheat based on gluten quantity and quality, essential for maximizing trade margins and supplying products suitable for varying end-use purposes.

Flour Milling

Millers can blend flour to meet end-user demands while not selling high quality product at a low price thereby improving operating margins. With the Gluten Index, the Wet Gluten Content and the Falling Number® analysis results available, millers can quickly predict the final baking quality, reducing the requirement for test baking.

Baking

The gluten properties and structure are important to:

• Form elastic dough
• Retain gas during fermentation and baking
• Allow expansion
• Carry expansion
• Retain the shape of loaf

As baking quality is both related to starch and protein characteristics, a combination of the results from the Falling Number® and Glutomatic® tests can be used to predict the baking quality. With the Gluten quality and quantity information at hand, bakeries are able to use the most cost effective grade of flour while still meeting end user quality. Maximizing the use of high quality flour and minimizing addition of expensive vital gluten results in substantial savings.

Durum and Pasta

The Gluten Index is reported worldwide in crop reports as an important quality indicator. During pasta manufacturing, gluten has great influence in:

• Forming non-sticky dough
• Achieving desired processing characteristics
• Maintaining firmness and cooking stability
• Obtaining products with desired cooking characteristics

About gluten

Gluten is the functional component of protein and determines many dough and processing characteristics of wheat and wheat flour. 

Gluten consists of the two proteins "Glutenin" and "Gliadin". It is not until a dough has been made that they actually form gluten. This is why it is not possible to determine gluten in wheat without actually making a dough. Flour, water and the energy from the kneading are all needed for gluten to form. A disulphide bond is then created between the glutenin and the gliadin as illustrated in the picture to the left. Click it to open a larger picture in a new window.

The protein content is a purely quantitative analysis that may or may not be indicative of protein quality. While gluten content and protein content are correlated, there are situations during which protein content will not be indicative of quality. These situations include:

• Variable Growing Conditions
• Yearly Growing Variation
• Wheat Varietal Variation
• Wheat or Flour Blends
• Heat Damage
• Bug Damage
• Enzymatic Addition

It is under these conditions when the reported protein content is not indicative of quality that another set of tests is required. The Glutomatic® system is designed to measure protein quality for the following parameters:

• Wet Gluten Content
• Dry Gluten Content
• Water Binding of Gluten
• Gluten strength by Gluten Index

The Gluten Index method

Overview

Wet Gluten is prepared from whole meal or flour by the Glutomatic® 2200 gluten washer. Gluten Index Centrifuge 2015 is used to force the wet gluten through a specially designed sieve cassette. The relative amount of gluten passing through the sieve indicates the gluten characteristics.The wet gluten is further dried in the Glutork 2020 for dry gluten content and water binding in the wet gluten calculation.

 

The steps in detail

The steps are illustrated in the picture above. Click the picture to enlarge it.

1. Weighing
   10.0 g ± 0.01 g of whole meal or flour is weighed and put into the Glutomatic® wash chamber with an 88 micron polyester sieve. When vital wheat gluten is measured, 1.5 ± 0.01 g is weighed.
2. Dispensing
   4.8 ml of salt solution is added to the meal or flour samples. No salt solution is added to vital wheat gluten samples.
3. Mixing
   Meal or flour and the salt solution are mixed to form a dough during 20 seconds.
4. Washing
   After termination of the mixing phase, the washing automatically starts and continues for five minutes. For wheat meal the sample is transferred to a chamber equipped with a coarse 840 micron sieve allowing bran particules to be washed out.
5. Centrifuging
   Exactly 30 seconds after completed washing, the undivided wet gluten piece is transferred to the special sieve cassette and centrifuged one minute at 6000 ± 5 rpm in Centrifuge 2015.
6. Weighing
   The fraction passed through the sieves is scraped off with a spatula and weighed. The fraction remaining on the inside of the sieve is collected and added to the balance. The total wet gluten weight is obtained.
7. Drying
   The total wet gluten piece is dried at min. 150°C during four minutes in the Glutork 2020. After drying the gluten is weighed on the balance.
8. Calculation
   The amount of gluten remaining on the centrifuge sieve in relation to total wet gluten weight is the Gluten Index.