Adding Peas to Snacks and Cereals - PulseResearch
April 25, 2017
Extrusion technology used to develop snacks and breakfast cereals from pulses
Promoted for their nutritional attributes and health benefits, pulses contain complex carbohydrates such as soluble and insoluble fibre, resistant starch, and oligosaccharides. They are high in protein, lysine, folate, and iron and they contain low levels of fat.
“These factors may contribute to reduced serum cholesterol and triacylglycerides, and may reduce the risk of diabetes, cancer, and heart disease,” says Shannon Hood- Niefer, the Vice President of Innovation and Technology at the Saskatchewan Food Industry Development Centre.
Despite all of that, pulses are currently underutilized in snack and breakfast foods due to some flavour related issues, the unique functionality of pulse flours when compared to corn flour or corn meal, and the lack of knowledge on the functionality of pulses when used in various products.
Previous research by Drs. Hood-Niefer and Robert Tyler, from Food and Bioproduct Sciences at the University of Saskatchewan, had demonstrated the feasibility of producing an expanded food product from air-classified pea starch and pea flour using extrusion technology. They conducted another study to look at using twin-screw, high temperature extrusion technology to develop snack and breakfast foods from pea flour, air-classified pea starch, and pea‑cereal blends.
“Extrusion cooking involves the use of temperature, pressure, and mechanical shear to generate finished shapes and products from raw ingredients,” Hood-Niefer says. “Extrusion processing technology is used to produce a variety of products, including expanded and flaked snack and breakfast foods, dry and semi-moist pet foods, confectionery products, texturized vegetable protein, pasta, and noodles.
“Extruders also can be employed as biochemical reactors to create new and innovative ingredients,” she adds, explaining screw extruders are the predominant extruder type used in the food and pet food industries. “Extrusion can be used to generate or reduce flavours in the extrudate as compared to the raw materials.”
Extrusion can drive off volatile flavours by venting or by using steam/moisture treatment. It can also generate new flavours using pressure and heat via caramelization or, depending on the nature of the ingredients, the Maillard reaction (or browning reaction), the chemical reaction between amino acids and reducing sugars that gives browned foods their desirable flavour.
The primary objective of this project was to identify extrusion conditions suitable for the production of expanded snack foods and breakfast foods from pea and other pulse ingredients, and pulse-cereal blends, and to prepare sufficient quantities of selected products for consumer and market testing.
Over the course of the project, which received funding from Saskatchewan Pulse Growers, Hood-Niefer and Tyler evaluated seven product shapes – small cylinders, large cylinders, loops, crisps, breadsticks, co-extruded pillows, and fried wavy chips – made from pulse and cereal ingredients in a variety of combinations and at various levels. Multiple salt and sugar levels and several flavourings were tested with some formulations.
Products were evaluated on the basis of appearance, expansion index, textural and sensory characteristics, and milk absorption, as appropriate.
In the end, the researchers concluded that the manufacture of a variety of extrudedexpanded snack foods and breakfast foods with satisfactory textural and sensory properties was feasible using pulse ingredients alone, or in combination with cereal ingredients, and that fibre content claims in Canada would be possible for some formulations.
Hood-Niefer says they are now taking what they learned and discussing the benefits of using pea flours and fractions in snacks and breakfast cereals with food processing companies, including some large multinational companies.
SPG Investment: $104,143
Project Length: 2 years
Dr. Shannon Hood-Niefer - Vice President of Innovation and Technology, Saskatchewan Food Industry Development Centre
Dr. Robert Tyler - Professor, Food and Bioproduct Sciences, University of Saskatchewan