The Effect of High‐Pressure Microfluidization Treatment on the Foaming Properties of Pea Albumin Aggregates

Abstract

The effect of dynamic high‐pressure treatment, also named microfluidization, on the surface properties of thermal pea albumin aggregates (AA) and their foaming ability was investigated at pH 3, 5, and 7. The solubility of albumin particles was not affected by the increase in microfluidization pressure from 70 to 130 MPa. Particle charge depended only on the pH, whereas protein surface hydrophobicity was stable at pH 5, decreased at pH 3, but increased at pH 7 after microfluidization treatment and with the applied pressure. Surface tension of AA measured at air/water interface was favorably affected by the microfluidization treatment at each pH preferentially due to size reduction and increased flexibility of protein particles. The foaming capacity and stability of AA depended on the pH conditions and the microfluidization treatment. The high‐pressure treatment had little influence in foaming properties at acidic pHs, probably related to a more compact form of AA at these pHs. At neutral pH, the foaming properties of pea AA were strongly influenced by their surface properties and size associated with significant modifications in AA structure with microfluidization. Changes in albumin aggregate characteristics with pH and microfluidization pressure are also expected to modulate other techno‐functional properties, such as emulsifying property. Practical Application Albumins are known for their interesting nutritional values because they are rich in essential amino acids. This fraction is not currently marketed as a protein isolate for human consumption, but can be considered as a potential new vegetable protein ingredient. This document demonstrated that heat treatment or dynamic high‐pressure technology can control the foaming properties of this protein for possible use in expanded foods.

Impact of microfluidization on colloidal properties of insoluble pea protein fractions

“…The dissociation of insoluble protein aggregates into so-called supramolecular aggregates with sizes < 1 µm upon homogenization has also been reported for faba bean protein (d H = 12 nm with detected particles up to 100 nm, p = 103 MPa for 6 cycles, pH 7) [27] and soy protein isolate (d H = 136 nm, p = 207 MPa for 30 cycles, pH unknown) [28]. Djemaoune et al [15] were able to decrease the hydrodynamic diameter of thermal pea albumin aggregates from 370 to 133 nm (p = 130 MPa for 3 passes, pH unknown).…”

“…For example, microfluidized pea protein emulsions showed a higher stability compared to ultrasonication as a result of smaller particle size and higher hydrophobicity [14]. Recently, microfluidization was applied to pea albumin aggregates to modulate their foaming properties [15]. Although homogenization is a well-established processing operation in dairy, juice, pharmaceutical, and chemical manufacturing, the molecular disruption mechanism of aggregates is still largely unknown compared to droplet breakup.…”

Plant Proteins for Future Foods: A Roadmap

“…The modification objectives for native and denatured proteins are anticipated to be different; therefore, it is better to separate the non-functional proteins from the native proteins. Some methods to transform non-functional proteins include thermal treatment [86] and micro-fluidization [83,87].…”

Future of Plant Protein Technology: Challenges and Opportunities

“…Another research direction in protein modification that can be explored is the transformation of denatured and/or aggregated non-functional plant proteins into functional plant proteins. Some methods employed to transform nonfunctional proteins include thermal treatment [44] and micro-fluidization [45,46]. There have been multiple reports related to physical, chemical, and biological methods aimed at improving the functionality of plant properties.…”