Thermo-induced changes in the structure of lentil protein isolate (Lens culinaris) to stabilize high internal phase emulsions

Author(s)

Galvao, Andressa Maria Medeiros Theophilo ; Freitas, Joao Cury ; Karatay, Graziele Grossi Bovi ; Furtado, Guilherme de Figueiredo ; Rasera, Mariana Lamy ; Tavares, Guilherme M. ; Hubinger, Miriam Dupas

• Document type: Journal article
• Source: International Journal of Biological Macromolecules; v. 253, p. 13-pg., 2023-10-12.

Abstract

This study aims to assess the impact of heat treatment on the emulsifying properties of lentil protein isolate (LPI) dispersion to produce high internal phase emulsions (HIPEs). The heat-treated LPI dispersion was characterized by size, turbidity, solubility, zeta potential, free sulfhydryl group, electrophoresis, differential scanning calorimetry, circular dichroism, Fourier transforms infrared spectroscopy and intrinsic fluorescence. HIPEs were produced with 25% of LPI dispersion (2%, w/w) and soybean oil (75%) using a rotor-stator (15,500 rpm/1 min). HIPEs were evaluated for their droplet size, zeta potential, centrifugal stability, microscopy, appearance, Turbiscan stability, and rheology over 60 days (25 degrees C). Heat treatment reduced the size of LPI, resulting in increased turbidity, solubility, and exposure of hydrophobic groups. HIPEs produced with heat-treated LPI at 70 degrees C (HIPE70) and 80 degrees C (HIPE80) for 20 min exhibited lower droplet sizes, increased stability, reduced oil loss, and a homogeneous appearance compared to HIPE produced with untreated LPI (HIPEc). In addition, HIPE70 and HIPE80 displayed resistance to shear stress, higher apparent viscosity, and increased storage modulus than HIPEc. HIPEs produced with heat-treated LPI were stable, suggesting that the treatment was efficient for improving the functional properties of the protein and the possibility of future research focusing on fat substitutes in food applications. (AU)

• FAPESP's process: 21/06863-7 - Use of protein and polysacharides to obtain structured oils:fat replacement and curcumin delivery
• Grantee: Miriam Dupas Hubinger
• Support Opportunities: Regular Research Grants
• FAPESP's process: 19/27354-3 - Architecture of colloidal delivery systems: what is the role of structure on the digestibility?
• Grantee: Rosiane Lopes da Cunha
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 18/03822-5 - Multi-user equipment approved in grant 2017/09214-4: preparative chromatography system - Akta pure (Ge healthcare)
• Grantee: Guilherme Miranda Tavares
• Support Opportunities: Multi-user Equipment Program