Strategies for structuring diverse emulsion systems by using wood lignocellulose-derived stabilizers

Abstract

Wood biomass is an abundant renewable source of materials, but due to the accelerating depletion of natural resources, it is important to explore new ways to use it in a more sustainable manner. Modern technologies enable the recovery and valorization of the main components of wood-namely, cellulose, lignin, and hemicelluloses-contributing to sustainability. However, the method of isolation and resulting structure and purity of lignocellulosic materials determine their functionality and applicability. This review discusses the properties of all three main wood-based compounds that can stabilize emulsions, a class of industrial dispersions that are widely used in life science applications and chemicals. Due to the multibillion-dollar annual market for hydrocolloids, the food, pharmaceutical, cosmetic, coating, and paint industries are actively seeking new sustainable emulsion stabilizers that fulfill the demanding requirements regarding safety and functionality. Wood-derived stabilizers facilitate various mechanisms involved in emulsion stabilization: (1) development of amphiphilic structures that decrease interfacial tension, (2) stabilization of interfaces by particles according to the Pickering theory, and (3) increase in the viscosity of emulsions' continuous phase. This review presents pathways for treating cellulose, lignin, and hemicelluloses to achieve efficient stabilization and provides suggestions for their broad use in emulsions.

Access to tough and transparent nanocomposites via Pickering emulsion polymerization using biocatalytic hybrid lignin nanoparticles as functional surfactants

“…This phenomenon could be associated to an increase in viscosity that counteracted electrostatic repulsion of the cationic particles and resulted in destabilization of the Pickering emulsions. 63 Our polymerization experiments were conducted by adding glucose (0.14 M) as a substrate for GOx and without applying any external degassing procedures. In all cases, almost quantitative monomer conversion (>90 %) was reached within 8 h, indicating an efficient enzyme catalyzed consumption of the dissolved oxygen during the whole polymerization process.…”

Spruce Galactoglucomannan-Stabilized Emulsions Enhance Bioaccessibility of Bioactive Compounds

“…We have previously shown that spruce-derived, hemicellulose-rich extracts function as an efficient emulsion stabilizer by providing protection against physical breakup and lipid oxidation [17][18][19][20][21][22]36]. These properties are ideal for the protection and delivery of sensitive bioactive components, such as polyunsaturated fatty acids.…”

“…In order to create a homogenous and stable mixture of lipophilic components and aqueous media, multifunctional stabilizers are needed. We have previously shown that GGM-rich extracts of spruce efficiently stabilize emulsions against physical breakup and inhibit lipid oxidation [17][18][19][20][21][22]. These are key features for the delivery and bioaccessibility of lipophilic compounds, for preserving bioactive components in the active state, and for avoiding the formation of adverse flavors caused by lipid oxidation.…”

“…We have previously shown that various different galactoglucomannan (GGM)-rich lignocellulosic extracts from Norway spruce (Picea abies) efficiently stabilize emulsions against physical breakup and lipid oxidation [16][17][18][19][20][21][22]. GGM are the main hemicelluloses in softwoods [11][12][13].…”

Valorization of Native Soluble and Insoluble Oat Side Streams for Stable Suspensions and Emulsions

“…However, even if in most of the cases extraction is carried out using water and food-grade solvents, an abundant part of the starting material is discharged. This makes sense in materials that are inedible by themselves, but that contain edible molecules, such as wood (Mikkonen 2020). In the case of fully edible materials, like in the case of bran, the extraction of emulsifiers can further generate waste material.…”