Impact of Surfactants on Nanoemulsions based on Fractionated Coconut Oil: Emulsification Stability and <i>in vitro</i> Digestion

Abstract

the seeds of Camellia sinensis L. which is the fruit of tea trees and currently a by-product of tea production. According to relevant data, the fatty acid composition ratio of green tea seed oil is most similar to that of olive oil and oleifera oil, but green tea seed oil is rich in natural tea polyphenols with characteristic indexes which is different from oleifera oil. Coconut oil is a mixture of various triglycerides, the content of lauric acid is more than 50 , and the content of C6, C8 and C10 fatty acids is above 15. Therefore, it is considered to be the richest source of medium-chain fatty acids. In addition, virgin coconut oil VCO retains a large amount of natural active substances such as vitamins, polyphenols and phytosterols because it Abstract: Functional oils have broad application prospects in functional foods and beverages because of their rich beneficial ingredients and healthier intake. The small droplets of the nanoemulsion enhance the effective delivery, solubility and bioavailability of the various hydrophobic food components. This study used a mixed oil phase of green tea seed oil and fractionated coconut oil, compared the emulsifying properties of natural surfactants: Whey protein isolate, soy lecithin, tea saponin and synthetic surfactant: Tween 80 in the preparation of nanoemulsions by ultrasonic method. In particular, the impact of emulsifier type and concentration, pH, ionic strength, and heat treatment on the mean particle size and ξ-potential were investigated. The long-term storage stability of the fabricated nanoemulsions was also monitored during storage at different temperatures. In addition, the effects of emulsifier type on the bioavailability of nanoemulsions were evaluated. For all nanoemulsions studied, the mean particle size decreasing with increasing emulsifier concentration. Tea saponin and soy lecithin can produce smaller droplets of nanoemulsion than Whey protein isolate. Tea saponin has the same emulsifying ability as Tween 80. Presumably tea saponin-stabilized droplets may be maintained by electrostatic repulsion and steric repulsion. All of the nanoemulsions significantly improved the bioavailability of the mixed oil phase compared to the unemulsified oil phase. This study highlights the potential of natural surfactants in the ultrasonic preparation of nanoemulsions containing functional oils, and provides a basis for the application of natural surfactants and new functional oils in food industry.

Saponins as Natural Emulsifiers for Nanoemulsions

“…Ralla et al studied the use of food byproducts, red beet ( Beta vulgaris L. ), and oat bran ( Avena sativa L. ), concluding that both obtained saponins present the necessary performance to be used as natural emulsifiers. Another example is the argan subproducts, namely the shells and oil press-cake, bioresidues rich in saponins that can act as surface-active components, enhancing droplet stability. , Lastly, the Camellia seed oil press-cake, which is generally disposed as waste, is a rich source of tea saponin and showed outcomes similar or even better than the extensively studied quillaja saponin, constituting a more sustainable and economically viable source of natural emulsifiers. , …”

“… 69 , 94 Lastly, the Camellia seed oil press-cake, which is generally disposed as waste, is a rich source of tea saponin and showed outcomes similar or even better than the extensively studied quillaja saponin, constituting a more sustainable and economically viable source of natural emulsifiers. 15 , 95 …”

“…Nanoemulsions can present different rheological, optical, and stability features depending on their composition (e.g., oil and emulsifier type), and preparation methods. For example, Gao et al 95 by modifying the emulsifier type (tea saponin, whey protein, soy lecithin, tween 80), and concentration (0.5–10% wt. ), obtained emulsions with quite different properties in terms of stability and optical appearance.…”

Wound Healing Activity of Opuntia ficus-indica Fixed Oil Formulated in a Self-Nanoemulsifying Formulation

“…29,30 On the contrary, the mean globule size reduction at higher surfactant could be ascribed to increased area at the water-oil interface due to the build-up of surfactant particles; this could potentially lead to reduced interfacial tension and protect against droplets coalescence. [31][32][33]…”

Production of tacrolimus using coconut oil as an alternative to glucose

“…It is important to mention that coconut oil also has a high concentration of bioactive compounds as vitamin E, sterols, and polyphenols (Gao et al, 2020). Vitamin E comprises eight compounds found in nature, four of them are tocopherols (α-, β-, γ-, δ-tocopherol) and four are tocotrineols (α-, β-, γ-, δ-tocotrienol).…”