Functional Grains Centre PhD candidate Mr Stephen Cork is investigating innovative processing techniques to add value to pulse crops.

He outlines his research below.

Pulses are a food of global significance due to their high protein, dietary fibre content and benefits to agriculture. Pulse consumption is below recommended levels in developed countries and is also declining in developing nations. Pulse flakes are currently only present in the ready-to-eat (RTE) market as niche products, but could be a means of increasing pulse consumption if the challenges of their structural weakness, “unpleasant” flavours and long cooking times can be overcome.

Focus on flakes

Partnering with Woods grains and Uncle Tobys we have produced a range of pulse flakes. Trials have included Australian hulled and split desi chickpeas, spilt faba beans, whole kabuli and whole desi chickpeas. Pulses were first precooked for six minutes with different steam injection times (one, three or five minutes). The precooked splits were then passed through a roller flaker with two different roller gaps and the pulse flakes were finally dried using a fluidized bed drier at either 150°C or 200°C.

This produced an exciting array of distinctive flakes as shown in figure 1. The flakes are only partially cooked and the degree of steaming primarily affected the moisture content. Higher moisture content improved ability of the pulse to pass through the rollers. Rolled flakes ranged in thickness from 0.6 - 1.9 mm due to the roller gap selected and formulation. Thicker flakes are more robust, but are relatively less robust compared to cereal flakes.

Pulse flakes maintain cell integrity and exhibit decreased intercellular adhesion compared to cereal flakes under the microscope. While flake processing subjectively softened the texture, shape and flavour of the final flake, further processing may be required to disrupt cellular structures to facilitate formation more homogenous robust matrix found in cereal flakes. Future work will evaluate the disruption of pulse cellular structures by extrusion into pellets and the effect on flake robustness.