092: Structural Modification of Lentil Proteins for Enhanced Hydrogel Particle Formation: Functional Improvement and Potential Applications in Food Products

Introduction

The functional properties of proteins play a key role in their diverse applications in food. Pulse crops are valuable food ingredients due to their high protein content, low cost, and nutritional benefits. Recently, there has been a growing emphasis on promoting pulse crops and pulse protein to enhance the sustainability of the global food supply. However, a critical challenge remains in modifying pulse proteins to optimize their functionality and broaden their application in food products.

Methods

In this study, we investigated the effects of pH shifting and heating treatment on the secondary structure of lentil protein. Hydrophobicity measurements were conducted to assess protein unfolding and used circular dichroism (CD) spectroscopy to monitor secondary structure changes. We also examined the potential of using modified proteins to form hydrogel particles with pectin through electrostatic complexation. Confocal laser scanning microscopy (CLSM) and static light scattering instruments were utilized to observe the formation of hydrogel particles. Finally, we explored these hydrogel particles as fat replacers to reduce fat content while preserving the product's structure and sensory attributes. The digestibility of modified proteins in hydrogel particles was evaluated compared to unmodified proteins.

Results

Our studies revealed that the secondary structure of lentil protein can be significantly altered through pH shifting and heating treatment. These modifications altered their compact globular conformations into more flexible structures and exposed more hydrophobic regions. The modified lentil proteins enhance their potential to form hydrogel particles with pectin through electrostatic complexation. In contrast, unmodified proteins could not form similar structures. The hydrogel particles showed potential as fat replacers by reducing oil content in emulsions while maintaining a creamy texture. Additionally, the modified plant proteins within hydrogel particles showed improved digestibility compared to the initial ones.

Significance

This research explores plant proteins' structural changes and modification patterns, providing valuable insights for optimizing pulse proteins in food systems. It also explores the underexamined link between protein molecular properties and structural characteristics of their electrostatic complexes with polysaccharides. The findings will enhance our understanding of plant proteins' structural modifications and functional properties. Additionally, it will support the innovative use of pulse proteins in the food industry.

Authors: Chenlu Ma, Zipei Zhang