Elsevier

Food Hydrocolloids

Volume 118, September 2021, 106612
Food Hydrocolloids

Review
Recent trends in oil structuring using hydrocolloids

https://doi.org/10.1016/j.foodhyd.2021.106612Get rights and content

Highlights

  • Oil structuring is an effective technology to replace solid saturated and trans fats.

  • Hydrocolloid-based oleogelation can be achieved through indirect methods.

  • Fundamental insights of oleogelation using protein and polysaccharides are discussed.

  • Research trends in hydrocolloid-based oleogels and gelled emulsions are evaluated.

Abstract

Solid fats provide desirable functionality, texture, and palatability to foods; however, they are related to adverse chronic health effects. Consumers and regulatory authorities are demanding more natural and healthy ingredients. Thus, in context of the high demand for healthy foods and the transition to more sustainable ingredients, oil structuring emerges as an outstanding strategy to substitute saturated and trans fats. Researchers have developed optimised indirect routes to structure oil with hydrocolloids resulting in gelled emulsions and oleogels. Novel healthy food structures based on polysaccharides, proteins, and their supramolecular interactions are suitable to create several types of healthy colloidal systems with unique sensory, texture, and stability properties.

Introduction

Oils and fats are important to our diet due to being an important energy source and solvent for key nutrients like vitamins and bioactive compounds. In foods, fats provide desirable functionality, texture, and palatability (Pehlivanoğlu et al., 2018). Fats had long been considered a bad influence on health, but, studies have shown that, principally, trans and some saturated fats are to blame (Liu et al., 2017; Zhu, Bo, & Liu, 2019). However, saturated fats have a technological role in foods because they are responsible for texture properties (Co & Marangoni, 2018). Solid-like lipids are preferred when processing some industrial products due to their specific features like better oxidative stability and solid lipid functionality. However, widely used methods, such as hydrogenisation, interesterification, and fractionation produce trans fatty acids which have severe adverse effects on coronary heart disease, blood lipoprotein profiles, diabetes, and cancer (Pehlivanoğlu et al., 2018). Academy researchers and research development experts have moved toward investigating ways for cheap and healthy production of solid fats with vegetable oil. Still, to replace saturated and trans fats in foods, maintaining their physicochemical and sensory properties is still a challenge (Iqbal, Xu, Huang, & Chen, 2019).

In the last decade, considerable progress in oil structuring technology has been made. Semisolid colloidal systems like oleogels incorporate a high percent of liquid oil within a structured network (composed by structurants) to give solid-like properties (Patel, Cludts, Sintang, Lesaffer, & Dewettinck, 2014). Moreover, highly concentrated gelled emulsions such as high internal phase emulsions (HIPEs) have gained popularity in this scientific field. However, an oleogelation limitation is the available food-approved structurants suitable for gelling liquid oils; of which hydrocolloids appear to be the most promising candidate. Generally, the gelling concentrations of hydrocolloids are remarkably low because of their large molecular sizes, making them efficient structuring agents. Still, most food-approved polymers are fundamentally hydrophilic and cannot be dispersed easily in oil to achieve the necessary structure and network formation required for gelation (Patel, 2018; Pernetti, van Malssen, Flöter, & Bot, 2007).

Hydrocolloid-based oleogelation is possible using indirect methods, an innovative solution to structure oil (Martins, Vicente, Cunha, & Cerqueira, 2018). This group includes: i) The emulsion-template approach where the emulsion formation is followed by evaporation of water, giving tightly packed droplets. ii) A solvent exchange procedure replacing the internal aqueous phase with an intermediate solvent followed by liquid oil. iii) The physical sorption of oil in porous structures such as aerogels or cryogels (Nephomnyshy, Rosen-Kligvasser, & Davidovich-Pinhas, 2020). In addition, HIPEs are templates to create oil continuous gels using low-temperature-triggered gelation of closely packed water droplets (Patel and Dewettinck, 2015).

Several types of hydrocolloids can produce novel structures because of their supramolecular interactions. Proteins are amphiphilic molecules that can adsorb strongly at an oil-water interface, thus are highly effective emulsifiers. Still, the functional properties of proteins can be lost in acidic conditions, at high temperature, high ionic strength, and in organic solvents, limiting their industrial uses (Akhtar & Ding, 2017). Polysaccharides are high-molecule-weight, hydrophilic, and biodegradable polymers regularly used as thickeners to affect the viscosity of aqueous phases to stabilise emulsions. However, many have poorer oil-water interfacial activity than proteins because of the lack of hydrophobic segments (Iqbal et al., 2019). The availability of many food-grade proteins and polysaccharides, and the versatility of the protein-polysaccharide interaction mechanisms, are fundamental to design suitable hydrogels that will later become oleogels (Anal, Shrestha, & Sadiq, 2019). These interactions have countless applications to improve the physical stability of the emulsion systems, and therefore in oleogels stabilisation.

Among indirect methods that require emulsification (such as the emulsion-template approach or HIPE gelation), a new category of food emulsifiers have increased interest from the oleogelation research field. Colloidal solid particles can form strong mechanical interfacial barriers via Pickering emulsions, anchoring at the interface as they can have an affinity for both oil and water (Berton-Carabin & Schroën, 2019). Interfacial layers containing Pickering particles give emulsions high physical stability, essential to develop stable gelled emulsions and oleogels (Lee, Tan, Ravanfar, & Abbaspourrad, 2019; Ma, Zou, McClements, & Liu, 2020).

In this review, the most recent insights of oleogelation using protein and polysaccharides are argued regarding the principal reasons that can influence the interactions and consequently the oleogelation. The promising hydrocolloid-based indirect oil structuration strategies, the development and incorporation of HIPE gels, and using Pickering emulsions with micro- and nanoparticles are discussed. Furthermore, functional colloid formation, current applications, and potential applications of structuring hydrocolloids are discussed.

Section snippets

Polysaccharides and proteins as structurants

Oleogelation is achieved by combining a structuring agent (structurant or oleogelator) with liquid oil to confer solid-fat functionality. Oil structuring agents can be classified into two groups based on their molecular weight: low and high molecular weight oil gelators (Co & Marangoni, 2018). High molecular weight oil gelators are mainly proteins and polysaccharides, which can form three-dimensional polymeric networks through physical interactions. Such oleogels have viscoelastic properties

Indirect methods to structuring liquid oils with hydrocolloids

The most common indirect methods include i) the emulsion-template approach, ii) a solvent exchange procedure, iii) physical sorption of oil into porous structures such as an aerogel or cryogel, and iv) HIPE gelation.

Conclusions

Under current demands for healthy, natural, and clean-label foods, plus a transition to more eco-friendly and sustainable ingredients, oil structuring using hydrocolloids has emerged as an outstanding strategy to substitute saturated and trans fats. Creation of oleogel systems using proteins and polysaccharides profit from hydrocolloid's proven structuring ability in food. However, hydrocolloids used as oil structuring agents raise a challenge due to their hydrophilic nature. Here, we have

Author statement

Pere Morell: Conceptualization, Writing – original draft, Isabel Hernando: Conceptualization, Writing- Reviewing and Editing, Funding acquisition. Amparo Quiles: Writing- Reviewing and Editing, Funding acquisition, Santiago Bascuas: Writing – original draft

Declaration of competing interest

The authors confirm there are not conflicts of interest.

Acknowledgements

The authors would like to thank Universitat Politècnica de València by FPI-UPV 2017 grant and the project RTI-2018-099738-B-C22 from the ‘Ministerio de Ciencia, Innovación y Universidades’. They would also like to thank Phillip John Bentley for assistance in correcting the English manuscript.

References (115)

  • I. De Marco et al.

    Life cycle assessment of supercritical impregnation: Starch aerogel + Α-tocopherol tablets

    The Journal of Supercritical Fluids

    (2019)
  • A. de Vries et al.

    Protein oleogels from heat-set whey protein aggregates

    Journal of Colloid and Interface Science

    (2017)
  • E. Dickinson

    Biopolymer-based particles as stabilizing agents for emulsions and foams

    Food Hydrocolloids

    (2017)
  • J. Gould et al.

    Interfacial and emulsifying properties of mealworm protein at the oil/water interface

    Food Hydrocolloids

    (2018)
  • X.N. Huang et al.

    Fabrication and characterization of Pickering High Internal Phase Emulsions (HIPEs) stabilized by chitosan-caseinophosphopeptides nanocomplexes as oral delivery vehicles

    Food Hydrocolloids

    (2019)
  • D. Huc-Mathis et al.

    Emulsifying properties of food by-products: Valorizing apple pomace and oat bran

    Colloids and Surfaces A: Physicochemical and Engineering Aspects

    (2019)
  • S. Iqbal et al.

    Structuring of water-in-oil emulsions using controlled aggregation of polysaccharide in aqueous phases

    Journal of Food Engineering

    (2019)
  • L. Jourdain et al.

    Stability of emulsions containing sodium caseinate and dextran sulfate: Relationship to complexation in solution

    Food Hydrocolloids

    (2008)
  • H. Khouryieh et al.

    Effects of xanthan-locust bean gum mixtures on the physicochemical properties and oxidative stability of whey protein stabilised oil-in-water emulsions

    Food Chemistry

    (2015)
  • C. Kleemann et al.

    Tailor made protein based aerogel particles from egg white protein, whey protein isolate and sodium caseinate: Influence of the preceding hydrogel characteristics

    Food Hydrocolloids

    (2018)
  • R. Li et al.

    Universal and simple method for facile fabrication of sustainable high internal phase emulsions solely using meat protein particles with various pH values

    Food Hydrocolloids

    (2020)
  • H.P. Lim et al.

    Pickering emulsion hydrogel as a promising food delivery system: Synergistic effects of chitosan Pickering emulsifier and alginate matrix on hydrogel stability and emulsion delivery

    Food Hydrocolloids

    (2020)
  • W. Liu et al.

    Stability, rheology, and β-carotene bioaccessibility of high internal phase emulsion gels

    Food Hydrocolloids

    (2019)
  • F. Liu et al.

    Pickering high internal phase emulsions stabilized by protein-covered cellulose nanocrystals

    Food Hydrocolloids

    (2018)
  • L. Manzocco et al.

    Exploitation of κ-carrageenan aerogels as template for edible oleogel preparation

    Food Hydrocolloids

    (2017)
  • A.J. Martins et al.

    Oleogels for development of health-promoting food products

    Food Science and Human Wellness

    (2020)
  • D.J. McClements

    Non-covalent interactions between proteins and polysaccharides

    Biotechnology Advances

    (2006)
  • Z. Meng et al.

    Effects of thickening agents on the formation and properties of edible oleogels based on hydroxypropyl methyl cellulose

    Food Chemistry

    (2018)
  • Z. Meng et al.

    Macro-micro structure characterization and molecular properties of emulsion-templated polysaccharide oleogels

    Food Hydrocolloids

    (2018)
  • K.S. Mikkonen et al.

    Prospects of polysaccharide aerogels as modern advanced food materials

    Trends in Food Science & Technology

    (2013)
  • B.S. Murray

    Pickering emulsions for food and drinks

    Current Opinion in Food Science

    (2019)
  • I. Nephomnyshy et al.

    The development of a direct approach to formulate high oil content zein-based emulsion gels using moderate temperatures

    Food Hydrocolloids

    (2020)
  • C.V. Nikiforidis et al.

    High internal phase emulsion gels (HIPE-gels) created through assembly of natural oil bodies

    Food Hydrocolloids

    (2015)
  • I.K. Oh et al.

    Utilization of foam structured hydroxypropyl methylcellulose for oleogels and their application as a solid fat replacer in muffins

    Food Hydrocolloids

    (2018)
  • I. Oh et al.

    Feasibility of hydroxypropyl methylcellulose oleogel as an animal fat replacer for meat patties

    Food Research International

    (2019)
  • M. Pernetti et al.

    Structuring of edible oils by alternatives to crystalline fat

    Current Opinion in Colloid & Interface Science

    (2007)
  • S. Plazzotta et al.

    Structure of oleogels from κ-carrageenan templates as affected by supercritical-CO 2 -drying, freeze-drying and lettuce-filler addition

    Food Hydrocolloids

    (2019)
  • S. Plazzotta et al.

    Structural characterization of oleogels from whey protein aerogel particles

    Food Research International

    (2020)
  • M. Rayner et al.

    Biomass-based particles for the formulation of Pickering type emulsions in food and topical applications

    Colloids and Surfaces A: Physicochemical and Engineering Aspects

    (2014)
  • J.M. Rodriguez Patino et al.

    Protein-polysaccharide interactions at fluid interfaces

    Food Hydrocolloids

    (2011)
  • Q. Ruan et al.

    Physical and tribological properties of high internal phase emulsions based on citrus fibers and corn peptides

    Food Hydrocolloids

    (2019)
  • E. Scholten

    Edible oleogels: How suitable are proteins as a structurant?

    Current Opinion in Food Science

    (2019)
  • E. Scholten

    Chapter 12 - Protein oleogels: network formation of proteins in hydrophobic conditions

  • M. Semenova

    Protein–polysaccharide associative interactions in the design of tailor-made colloidal particles

    Current Opinion in Colloid & Interface Science

    (2017)
  • C.H. Tang

    Nanostructured soy proteins: Fabrication and applications as delivery systems for bioactives (a review)

    Food Hydrocolloids

    (2019)
  • S. Tang et al.

    Interfacial and enhanced emulsifying behavior of phosphorylated ovalbumin

    International Journal of Biological Macromolecules

    (2019)
  • R. Tanti et al.

    Hydroxypropyl methylcellulose and methylcellulose structured oil as a replacement for shortening in sandwich cookie creams

    Food Hydrocolloids

    (2016)
  • R. Tanti et al.

    Oil stabilization of natural peanut butter using food grade polymers

    Food Hydrocolloids

    (2016)
  • I. Tavernier et al.

    Emulsion-templated liquid oil structuring with soy protein and soy protein: κ-Carrageenan complexes

    Food Hydrocolloids

    (2017)
  • I. Tavernier et al.

    Food-grade particles for emulsion stabilization

    Trends in Food Science & Technology

    (2016)
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    Santiago Bascuas and Pere Morell contributed equally to this work as first authors.

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