Processing pulses through puffing, flaking, and milling into flour can improve their nutritive value by reducing anti-nutritional factors. Puffing exposes grains to high steam pressure which causes them to burst open and expand in size. Flaking involves partially cooking grains through steaming then pressing or rolling them into thin crispy flakes. Milling grains in plate, roller, or hammer mills produces pulses flours. Soaking, puffing, flaking, and milling techniques can increase the protein, fiber, and mineral content of pulses while decreasing compounds responsible for flatulence.

1. Processing of Pulses
(Puffed, Flaked & Flour)
By,
Karthi

2. Introduction
 Pulses – part of Legume family.
 High in protein, fibre, & minerals (Zn, Iron, phosphorous, vitamins)
 Low in fats
 The pulses are nutritionally important since they usually provide the bulk of the
diet. They are also a relatively cheap source of energy, protein, and important
vitamins and minerals.
 Processing of pulses is important in improving their nutritive value.
 Processing techniques include puffing, flaking and milling.
 Soaking in water is the first step in preparing pulses for consumption.
 Soaking reduces anti-nutritional factors present in pulses.
 Soaking reduces the oligosaccharides of the raffinose family, which are responsible for
flatulence after pulse consumption.
 Soaking also reduces the amount of phytic acid in pulses.

3. Puffing Processing
 During puffing, grains are exposed to a
very high steam pressure, which causes
the grains to burst open.
 Puffed grains and pulses may be further
processed by toasting, coating, or
mixing with other ingredients.

4. Sand roasting method:
 Pulses are exposed to hot sand, while temperature of sand is about 250°C.
 Due to sudden thermal gradient, the moisture inside the grains vaporizes and tries to
escape through the micropores, expanding the starchy endosperm in size in this process .
 Bengal gram can also be puffed when the preliminary roasting of grains with sand at
170°C for 75 s & then soaked in water for 5 seconds and impacted between a roller and a
hot plate for de-husking and splitting.
 Under these conditions the bulk volumes of grains doubled during puffing
 Gun puffing is a process in which the milled grains are introduced in to the gun or high
pressure chamber after preheating, and then a superheated steam is introduced to the closed
rotating chamber
 The steam pressure is critical - final texture - puffed product, as too low pressure would
result in product lacking crispiness and too high pressure would shatter the pulses.
 Sufficient time is allowed for the superheated steam to cook the grain in semi-plastic state
and in the end, the pressure is suddenly released for obtaining the crispy puffed grain.

5. The temperature ranging from 240°C to 270°C with corresponding exposure time
of 7 to 9.7 s was found to be optimum for higher expansion ratio (8.5 to 10) and
better colour of the product

6. Flaked products
 Before flaking, grains and pulses are softened by being partially cooked in steam.
 They are then pressed or rolled into flakes which are subsequently dried.
 Such partially cooked pulses / cereals may be used as quick cooking or ready to eat
foods.
 Both flaked and puffed grains are eaten crisp and need to be packaged in moisture-proof
containers.
 The moisture content must be below 7 per cent, otherwise the product becomes soggy and
tough.

7.  Flaked pulses is a thin crispy snack. It is mainly used
as Breakfast cereal.
 It can easily be soaked in cold or hot water.
 The sample to be Graded, sorted & soaked in hot
water for about 12 to 18 hours and then roasted with
fine sand in roaster.
 Soaked sample is flattened between rollers in a
flaking machine until wafer thin.
 The pulses are pressed into fine flakes and bran is
powdered and drops down through sieves.
 Flattened/flaked pulses are mechanically dried.
 Depending on the weight of the rollers flakes of
varying thickness from translucent to thick and
opaque are manufactured.

8. Flour processing
Milled products
 Grains and pulses are milled to
produce flours which are used to
produce many types of food.
Three main types of mill are
available:
 Plate mill
 Roller mill
 Hammer mill.
 The choice of mill will depend on
the raw material

10. Reference
 Popping and Puffing of Cereal Grains: A Review, Gayatri Mishraa*, D.C. Joshib
and Brajesh Kumar Pandaa Journal of Grain Processing and Storage | July-
December, 2014 | Vol 1 | Issue 2 | Pages 34-46 © 2014 Jakraya Publications (P)
Ltd
 Improving the value of Australian pulses through puffing Author: S. P.
Mukhopadhyay, J. A. Wood, P. D. Prenzler, C. L. Blanchard and A. J. Saliba S. P.
Mukhopadhyay1,2, J. A. Wood1,3, P. D. Prenzler1,2, C. L. Blanchard1,4, A. J.
Saliba5

11. Thank you