Brabender and Müller's Mühle successfully test new time-saving method for determining the quality of pulses.

Legumes, such as lentils, peas and beans, have gained importance in human nutrition in recent years due to their high protein and fiber content. Legumes also score well in the area of sustainability when it comes to cultivation because of their low water and fertilizer requirements.

This is because they bind nitrogen from the atmosphere and pass on a large part of the nutrient to subsequent crops, so that less nitrogen fertiliser is needed. A side effect is that the CO2 footprint that results from the cultivation of crops is reduced by increasing the cultivation of legumes. In addition, pulses are suitable for people who follow different dietary concepts, such as gluten-free, high protein or vegetarian. That is why they are often used as a basic ingredient for meat substitutes. When making meat substitutes from legume flour, the oil absorption properties of the flour are important in terms of the appropriate oil addition for an extrusion process, and finally also to ensure that the end product is succulent enough.

OIL ABSORPTION OF LENTIL FLOUR

In cooperation with the company Müller's Mühle, Brabender therefore carried out a quality analysis determination of different pulses, including lentils, peas, faba beans and chickpea, and presented the results at the last conference for bakery technology in Detmold, Germany. In addition to the water absorption and gelatinisation properties of legume flour, the two companies also determined the oil absorption of lentil flour and developed a time-saving measuring method: "We filled legume flour into our measuring mixer and measured the torque during the mixing process with our Absorptometer C to determine the oil absorption, while an automatic precision metering pump continuously added the oil. Normally we only use the Absorptometer for carbon black and silica in the chemical sector", explains Jessica Wiertz, Manager Applications at Brabender. Within three minutes, with little influence from the operator and only a few steps, the oil absorption of the flour could be determined.

MANUAL METHOD IS MUCH MORE TIME-CONSUMING

The classical determination of the oil absorption of flour by means of the pipetting method requires significantly more work steps and takes more than an hour: "Using the classical method, many more manual work steps are necessary. The flour-oil mixture is centrifuged several times, it has to stand out, be heated, decanted, drained and balanced", says Wiertz. In addition, these are all manual steps, which depend on the operator: "Of course, this is all very small-scale and does not work automatically, as it does with the Absorptometer", adds Jessica Wiertz. In the future, the process will be further optimised and also tested with other legume crops. "After analysing the flours, we have also extruded different types of meat analogues. We have tested the process with faba beans, but that tastes quite beany as a sole ingredient for meat substitutes. Faba bean mixed with yellow peas, for example, is recommendable in terms of taste", Wiertz reveals. Besides meat substitutes, other products can also be developed by extrusion from pulses. These include gluten-free pasta made from lentils and expanded lentil snack food. 

About the author

Jessica Wiertz has been with Brabender since 2016. There, she initially managed the application laboratory for food and feed, and is now responsible for the company's application technology division. After studying food technology at today‘s Technische Hochschule Ostwestfalen-Lippe, she first worked in the quality assurance department of an industrial bakery and afterwards as a laboratory engineer in the laboratory for food technology at Hochschule Osnabrück.