Protein extrusion from maize, Phaseolus vulgaris and Amaranthus cruentus L.

Overview

This research investigates how the botanical origin of plant-based proteins influences their structural modification during extrusion processing. The study focuses on proteins from three distinct sources: maize, Phaseolus vulgaris (common bean), and Amaranthus cruentus L. (amaranth). The central hypothesis is that the molecular structure and functional characteristics of these proteins, which are tied to their botanical origin, determine their processability and performance in extruded food systems.

Under extrusion conditions, proteins and starches undergo significant structural changes, including protein unfolding and starch breakdown, which directly affect the sensorial characteristics of expanded snack products. Understanding these relationships enables more targeted formulation of plant-based extruded foods with predictable quality attributes.

Technical specifications

Research approach:

• Analysis of protein isolates for molecular weight, functional properties, glass transitions, and digestibility
• Extrusion testing of plant-based proteins in both whole flour and isolated protein forms
• Blending of proteins with a selected starch according to an experimental design
• Processing using a twin-screw extruder (DS 32-II Jinan Saixin Machinery Co., China) under varying heat and mechanical input conditions
• Characterization of extrudates for shear strength via texture analysis
• Determination of expansion ratios and densities
• Assessment of the extent of protein breakdown during processing

Key variables under investigation:

• Botanical origin of protein source (maize, common bean, amaranth)
• Protein form (whole flour vs. isolated protein)
• Thermal and mechanical energy inputs during extrusion
• Structural modifications and their correlation with textural and sensorial outcomes

Technology readiness level

This research is at an early-to-mid stage of development. Future validation plans include comprehensive characterization of protein isolates and systematic extrusion trials using a twin-screw extruder to establish correlations between botanical origin, processing parameters, and product quality. The work represents applied food science research with potential implications for the development of plant-based expanded snack products, though commercial-scale validation has not yet been undertaken.