Development and optimization of plant-based protein isolates from underutilizedlegumes for burger patties with enhanced texture and shelf stability

Project Abstract

This study reports the development and optimization of plant-based protein isolates derived from underutilized legumes for use in burger patties, focusing on texture enhancement and shelf stability. A systematic extraction protocol leveraging aqueous and alkaline solubilization followed by isoelectric precipitation was developed to maximize protein yield while preserving functional properties such as solubility, emulsification, and water-holding capacity. Legume species including jack beans, pigeon peas, and faba beans were screened for protein content, antinutritional factors, and techno-functional performance. Extracted isolates were subjected to factorial experimental design to optimize pH, ionic strength, temperature, and centrifugation conditions, aiming to achieve high protein content (>85%), minimal residual antinutritional factors, and robust gel-forming ability. Characterization encompassed proximate analysis, Fourier-transform infrared spectroscopy, differential scanning calorimetry, and scanning electron microscopy to elucidate structural changes associated with processing, as well as SDS-PAGE to evaluate protein profiles. Functional assessment demonstrated that optimized isolates exhibited superior water-binding capacity and oil-holding capacity relative to conventional soy and pea proteins, contributing to improved juiciness and mouthfeel in formulated patties. Rheological measurements indicated enhanced viscoelastic properties and a more cohesive dough matrix, facilitating burger patty integrity during processing and cooking. Texture profile analysis revealed higher hardness, cohesiveness, and chewiness in patties formulated with the optimized isolates, approaching the sensory attributes of conventional meat patties while maintaining reduced lipid oxidation and moisture loss upon thermal exposure. Microbial shelf-life evaluation under accelerated storage conditions showed a marked improvement in stability, with isolates contributing to lower syneresis and delayed flavor degradation; packaging trials with modified atmosphere environments further extended sensory acceptability beyond 21 days at refrigeration temperature. Food safety and nutritional profiling indicated that the isolates provided a balanced amino acid pattern with lysine and methionine enrichment, aligning with recommended daily allowances. Sensory evaluation by trained panels corroborated acceptability in texture, flavor, and overall likability, with consumer subset testing confirming market-ready potential for plant-based patties. Life cycle assessment highlighted reduced environmental impact relative to animal-based patties, particularly in land use and greenhouse gas emissions, while energy inputs remained within industry-standard processing ranges. The study also explored scaling considerations, including pilot-scale extraction feasibility, waste valorization of fermentation by-products, and cost-analysis suggesting competitive production costs under optimized operational parameters. Overall, the work demonstrates that underutilized legume protein isolates can be tailored to deliver desirable textural attributes and enhanced shelf stability in burger patties, offering a sustainable alternative with potential for broad application in plant-based protein product development.

Project Overview

What This Project Is About

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A plain-language overview of creating and testing plant-based protein powders from less-common edible plants to be used in burger patties, focusing on texture and how long they stay fresh on the shelf. The project looks at simple steps to turn plant materials into usable protein ingredients, how these ingredients affect burger texture, and how to keep patties from spoiling quickly without relying on artificial additives. It also considers cost, availability, and consumer appeal.

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The Problem It Addresses

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Many plant-based burgers rely on a few common crops, which can be costly or unsustainable. Some underutilized legumes offer good protein but are rarely worked into meat substitutes. The project aims to unlock these resources, improve texture to mimic real meat, and extend shelf life, benefiting both food security and climate-friendly diets.

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Objectives of the Project

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1. Identify underutilized legumes with high protein potential.
2. Extract and prepare protein isolates suitable for burgers.
3. Test how different isolates affect burger texture and juiciness.
4. Evaluate shelf life under common storage conditions.
5. Recommend formulations that balance texture, flavor, and stability.

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What You Will Do Step by Step

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1. Review literature on plant proteins and burger textures.
2. Source underutilized legumes and produce protein isolates.
3. Prepare burger patty tests with various isolates.
4. Cook patties and measure texture properties (e.g., firmness, cohesiveness).
5. Conduct shelf-life tests (appearance, aroma, microbial checks).
6. Analyze data to compare performance and determine best formulas.
7. Discuss results and potential improvements for scale-up.

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Expected Outcome

A set of burger patty formulations using new plant proteins that offer good texture and longer shelf life, with clear guidelines for selection, processing steps, and practical considerations for production and consumer acceptance.