Tailoring quality in plant protein-rich aerated puffed extruded snacks

Overview

This research program addresses a critical challenge in the healthy snack industry: producing puffed extruded snacks with elevated plant protein content without sacrificing the appealing aerated texture that consumers expect. The team investigates how extrusion conditions, protein chemistry, melt rheology, and glass transition behaviour interact to shape snack structure. A central innovation involves the use of well-defined physical blowing agents such as nitrogen gas and air to engineer bubble formation during extrusion, mitigating the textural and structural impairment that typically accompanies protein enrichment. The goal is to enable production of nutritionally dense, high-protein puffed snacks that maintain sensory appeal.

Technical specifications

Core research capabilities:

• Extrusion cooking at both research and pilot scale, with and without physical blowing agents
• Protein and starch characterization across diverse cereals, grains, and plant protein sources
• Melt rheology analysis to understand how proteins influence flow behaviour during processing
• Investigation of bubble nucleation, growth, and collapse dynamics in protein-rich extrudates
• Glass transition temperature analysis linked to bubble stability and structural setting
• Sensory evaluation covering texture, structure, and flavour
• Nutritional quality assessment including starch, in vivo, and in vitro protein digestibility
• Protein blending strategies to balance nutritional density with sensory quality

Interdisciplinary team composition:

• Food engineers, chemists, and nutritionists with deep experience in extruded food systems
• Established track record in navigating complex formulation interactions including protein denaturation, starch interactions, and melt rheology

Technology readiness level

The program is at a foundational research stage focused on building a predictive model for extruding protein-rich ingredients. Future validation efforts will investigate the role of protein in melt rheology and bubble nucleation, the relationship between glass transition and bubble collapse, the impact of blowing agents on aerated structure, and the blending of protein sources for optimized nutritional and sensory outcomes. The team will test a variety of ingredients to ensure broad applicability of findings. Outputs will include foundational knowledge on extrusion rheology and bubble dynamics, as well as strategies and models for producing high-protein puffed snacks at scale.