Consumer concern about human and environmental health is encouraging food manufacturers to use more natural and sustainable food ingredients. In particular, there is interest in replacing synthetic ingredients with natural ones, and in replacing animal-based ingredients with plant-based ones. This article provides a review of the various types of natural emulsifiers with potential application in the food industry, including phospholipids, biosurfactants, proteins, polysaccharides, and natural colloidal particles. Increased utilization of natural emulsifiers in food products may lead to a healthier and more sustainable food supply. However, more research is needed to identify, isolate, and characterize new sources of commercially viable natural emulsifiers suitable for food use.

Recent Advances in the Utilization of Natural Emulsifiers to Form and Stabilize Emulsions.

Background Proteins from different sources serve as primary food components, while polyphenols, as secondary metabolites, are abundantly present in plant. Both components play an important role in functional properties and quality of food products. Interaction between proteins and polyphenols, yielding “protein-polyphenol conjugate”, spontaneously occurs in most of food systems, and is known to have an impact on sensorial, functional, and nutraceutical properties of the food products. Scope and approach Protein-polyphenol conjugate can be implemented for improvement of food quality. In this article, mechanism and factors affecting protein-polyphenol interactions as well as the functionalities of protein-polyphenol conjugates, especially solubility, thermal stability, emulsifying, gelling and antioxidant properties, are revisited. The information on potential applications of protein-polyphenol conjugates in emulsions, protein-based films, and protein gels, as well as conjugates-based delivery systems is also discussed and reviewed. Key findings and conclusions The interaction of proteins and polyphenols mainly results from non-covalent (H-bonding, electrostatic interactions) or covalent bonds taking place mostly based on the oxidation of proteins or polyphenol by enzymatic or non-enzymatic pathways. Moreover, protein-polyphenol interaction greatly depends on environmental conditions such as temperature and pH as well as on the conformation or type of proteins and polyphenols. The protein-polyphenol conjugates with higher thermal stability, antioxidant activities, better emulsifying properties and enhanced gelling property can be used as novel food additives for improvement of functionalities and quality of food products.

Protein–polyphenol conjugates: Antioxidant property, functionalities and their applications

Application of whey protein isolate and low-methoxy pectin-based fat mimetics in mayonnaise was studied. Fat was partially substituted by different fat mimetics at levels of 50%, respectively, which the fat mimetics were referred to as PFM1 (microparticulate pectin gel), PFM2 (pectin weak-gel), and PFM3 (microparticulated combination of WPI and pectin). The full fat (Ff) (100% oil) mayonnaise without fat mimetic was used as a control experiment. Physicochemical, rheological, texture analysis, and sensory evaluation of the Ff and low fat (Lf) mayonnaises were performed. The results indicated that all Lf mayonnaises had significantly lower energy content, but higher water content than their Ff counterpart. In terms of texture, the formulation with pectin weak-gel as fat mimetic showed similar texture values as those of the Ff sample. Both Ff and Lf mayonnaises exhibited thixothopic shear thinning behaviour under steady shear tests and were rheologically classified as weak gels under small amplitude oscillatory shear tests. Sensory evaluation demonstrated that mayonnaises substituted with low-methoxy pectin were acceptable. This study shows good potential for pectin weak-gel and microparticulated pectin gel to be used as a fat mimetic in mayonnaise.

Rheological, texture and sensory properties of low-fat mayonnaise with different fat mimetics

https://hal.archives-ouvertes.fr/hal-02330281/document

Pickering emulsions: Preparation processes, key parameters governing their properties and potential for pharmaceutical applications.

There has been strong interest in developing effective strategies to inhibit lipid oxidation in emulsified food products due to the need to incorporate oxidatively labile bioactive lipids, such as w-3 fatty acids, conjugated linoleic acids, or carotenoids. Emulsifiers or co-emulsifiers can be utilized to inhibit lipid oxidation in emulsions. Both of these molecular types can adsorb to droplet surfaces and inhibit lipid oxidation, but emulsifiers can also stabilize droplets against aggregation whereas co-emulsifiers cannot. There are a host of existing emulsifiers, covalent conjugates, or physical complexes that have the potential to inhibit lipid oxidation by a variety of mechanisms. Existing emulsifiers with antioxidant potential consist of surfactants, phospholipids, proteins, polysaccharides and colloidal particles. Conjugates and complexes are typically formed by covalently or physically linking together a surface-active molecule with an antioxidant molecule. This article, reviews the molecular and ph...

Interfacial Antioxidants: A Review of Natural and Synthetic Emulsifiers and Coemulsifiers That Can Inhibit Lipid Oxidation.

Selenium-enriched egg white peptides (Se-EWP) were prepared by pre-heat treatment and enzymatic hydrolysis in this study. In addition, their selenopeptide sequence identification and immunomodulatory effect were investigated. Results showed that the yield of Se-EWP obtained from alkaline-neutral protease treatment reached 76.90%, and peptides with a molecular weight of 200-1000 Da accounted for 98.33%. Four characteristic selenopeptides, including SeCys-Trp-Leu-Glu, Trp-Ser-SeCys, SeMet-Ala-Pro, and SeMet-Leu, were identified by HPLC-ESI-MS/MS, which were rich in hydrophobic and branched-chain amino acids. Se-EWP (750 mg/kg/d) could effectively retard the decrease of immune organ index in immunosuppressed mice induced by cyclophosphamide. Moreover, supplementation of Se-EWP could promote a higher content of Se in liver, the number of white blood cells, and the levels of serum cytokines (IL-6, IL-2, and TNF-α) as compared with EWP groups, indicating that Se-EWP could effectively alleviate immunosuppression induced by cyclophosphamide. These findings suggested that Se-EWP exhibited great potential as functional foods for immunomodulatory effect.

Identification and Immunomodulatory Effect on Immunosuppressed Mice of Selenium-Enriched Peptides of Egg White.

Selective adsorption of egg white hydrolysates onto activated carbon: Establishment of physicochemical mechanisms for removing phenylalanine

Encapsulation of amino acids in water-in-oil-in-water emulsions stabilized by gum arabic and xanthan gum.

BACKGROUND
Egg yolk granules (EYG)-soy lecithin (SL) complex is newly developed delivery system that is effective in improving the storage stability of hydrophobic bioactive compounds. However, the formation mechanism of egg yolk granules (EYGs) and soy lecithin (SL) complex and it effect on the gastrointestinal fate of lutein-loaded emulsions need to be further investigated.


RESULTS
Adding SL greatly improved the surface activity of the EYGs evidenced by reduced surface tension and increased adsorption rate to the oil/water interface. Hydrophobic interaction was the dominant force in the formation of EYG-SL complex with hydrogen and ionic bonds playing complementary roles. Using the EYG-SL complex, stable oil-in-water emulsions were formed and exhibited enhanced retention ratio and bioaccessibility of lutein after simulated digestion. Correlation analysis demonstrated that the additional anti-oxidant activity brought by EYGs was responsible for the high retention of lutein whereas low surface tension facilitated the micellization of bioaccessible lutein.


CONCLUSION
This study shows that the EYG and SL have synergistic effect in improving the retention ratio and bioaccessiblity of lutein in emulsions stabilized by EYG-SL complex after digestion and will guide the development of value-added oil-in-water emulsion product using protein-lecithin complex as a promising nutrient delivery vehicle. This article is protected by copyright. All rights reserved.

Cuihua Chang

Papers

Identification and Immunomodulatory Effect on Immunosuppressed Mice of Selenium-Enriched Peptides of Egg White.

Selective adsorption of egg white hydrolysates onto activated carbon: Establishment of physicochemical mechanisms for removing phenylalanine

Encapsulation of amino acids in water-in-oil-in-water emulsions stabilized by gum arabic and xanthan gum.

Improved retention ratio and bioaccessibility of lutein loaded in emulsions stabilized by egg yolk granules-lecithin complex.

Fabrication, characterization, and application of catechin-dextran-egg white protein conjugates: Novel antioxidant emulsifiers