Lipid nanoparticles as vitamin matrix carriers in liquid food systems: On the role of high-pressure homogenisation, droplet size and adsorbed materials

Over 100 years of vitamin E: An overview from synthesis and formulation to application in animal nutrition

The groundbreaking discovery of vitamin E by Evans and Bishop in 1922 was an important milestone in vitamin research, inspiring further investigation into its crucial role in both human and animal nutrition. Supplementing vitamin E has been proved to enhance multiple key physiological systems such as the reproductive, circulatory, nervous and muscular systems. As the main antioxidant in the blood and on a cellular level, vitamin E maintains the integrity of both cellular and vascular membranes and thus modulates the immune system. This overview showcases important and innovative routes for synthesizing vitamin E on a commercial scale, provides cutting-edge insights into formulation concepts for successful product form development and emphasizes the importance and future of vitamin E in healthy and sustainable animal nutrition.

Nanoemulsion of Minthostachys verticillata essential oil. In-vitro evaluation of its antibacterial activity

Infectious diseases constitute a problem of great importance for animal and human health, as well as the increasing bacterial resistance to antibiotics. In this context, medicinal plants emerge as an effective alternative to replace the use antibiotics. The essential oil (EO) of Minthostachys verticillata (Griseb.) Epling (Lamiaceae) has demonstrated a strong antimicrobial activity. However, its instability and hydrophobicity under normal storage conditions are limitations to its use. Nanoemulsion technology is an excellent way to solubilize, microencapsulate, and protect this compound. This study aimed to obtain a nanoemulsion based on M. verticillata EO and evaluate its antibacterial activity against Staphylococcus aureus. The EO was obtained by steam distillation. Identification and quantification of their components were determined by GC-MS revealing that the dominated chemical group was oxygenated monoterpenes. Nanoemulsions (NE) were characterized by measuring pH, transmittance, separation percentage, release profile, and morphology. The effect of NE on the growth of S. aureus and cyto-compatibility was also evaluated. The results showed that NE containing a higher percentage of tween 20 exhibited higher stability with an approximated droplet size of 10 nm. The effect of encapsulation process was evaluated by GC-MS revealing that the volatile components in EO were no affected. After 24 h, 74.24 ± 0.75% of EO was released from NE and the antibacterial activity of EO was enhanced considerably by its encapsulation. The incubation of S. aureus with the NE and pure EO, show a bacterial growth inhibition of 58.87% ± 0.99 and 46.72% ± 3.32 (p < 0.05), respectively. In addition, nanoemulsión did not cause toxicity to porcine and equine red blood cells. The results obtained showed that NE could be a potential vehicle for M. verticillata EO with promissory properties to emerge as a tool for developing advanced therapies to control and combat infections.

Microencapsulation of oil and protein hydrolysate from fish within a high-pressure homogenized double emulsion

In this study, the effect of high-pressure homogenization on the water-in-oil-in-water (W₁/O/W₂) double emulsions containing fish protein hydrolysate and fish oil encapsulated within a complex of whey protein concentrate and inulin were investigated in order to produce stable double emulsion. After adequacy of the positive influence of high-pressure homogenization at W₁/O (one pass) and W₁/O/W₂ (three passes), the double emulsions were produced with (H) and without (HS) high-pressure homogenization. H samples were demonstrated lower CI of double emulsion and higher amounts of yield, total oil, encapsulated oil, EPA and DHA of microcapsules in comparison with HS samples. At subsequent step, response surface methodology were applied to optimize the high-pressure homogenization conditions (700-1500 Ba) of double emulsions in terms of minimum CI of emulsions and maximum microencapsulation efficiency and oxidation stability. Optimal conditions were obtained by using high-pressure homogenization at 1000 and 1100 Ba on W₁/O and W₁/O/W₂, respectively.

Low-Energy Encapsulation of α-Tocopherol Using Fully Food Grade Oil-in-Water Microemulsions

Encapsulation of active agents, such as vitamins and antioxidants, is one of the possibilities that allow their incorporation in beverages, food, or in pharmaceutical products. Simultaneously, encapsulation protects these active agents from oxidation, producing more stable active compounds. Formation of nanodroplets by spontaneously formed microemulsion (ME) offers, on one hand, a low-energy technology of encapsulation and, on the other hand, because of a small size of the droplets, it assures long-term stability even in harsher environments. In this study, oil-in-water MEs allowed the low-energy encapsulation of α-tocopherol (αToc) into an aqueous medium with the aid of fully food-grade ingredients, using isoamyl acetate as the dispersed oil phase, which was selected between three different types of oils. Both cosurfactant-free and cosurfactant-holder ME systems were formulated, in which Tween 20 and glycerol were employed as the surfactant and the cosurfactant, respectively. The ME monophasic area was determined through the construction of pseudoternary phase diagrams. The encapsulated αToc within 10-20 nm nanocapsules showed radical scavenging activity dependent on the encapsulated amount of αToc, as it was demonstrated by electron paramagnetic resonance spectroscopy. The radical scavenging activity slightly increased within the time investigated, indicating a slow release of the active compound from the nanodroplets, which is a promising result for their application, especially in pharmaceuticals.

Edible Nanoemulsions as Carriers of Active Ingredients: A Review

There has been growing interest in the use of edible nanoemulsions as delivery systems for lipophilic active substances, such as oil-soluble vitamins, antimicrobials, flavors, and nutraceuticals, because of their unique physicochemical properties. Oil-in-water nanoemulsions consist of oil droplets with diameters typically between approximately 30 and 200 nm that are dispersed within an aqueous medium. The small droplet size usually leads to an improvement in stability, gravitational separation, and aggregation. Moreover, the high droplet surface area associated with the small droplet size often leads to a high reactivity with biological cells and macromolecules. As a result, lipid digestibility and bioactive bioavailability are usually higher in nanoemulsions than conventional emulsions, which is an advantage for the development of bioactive delivery systems. In this review, the most important factors affecting nanoemulsion formation and stability are highlighted, and a critical analysis of the potential benefits of using nanoemulsions in food systems is presented.

Degradation of Vitamin E in Nanoemulsions during Storage as Affected by Temperature, Light and Darkness

Vitamin E (VE) nanoemulsions confront physical instabilities and chemical degradation during processing and/or storage. Therefore, thermal stability and degradation kinetics of VE in nanoemulsions fabricated using low-energy emulsification method as a function of temperature under light and in the dark were studied. Nanoemulsions had small droplet diameter (≈110 nm). The thermal degradation of VE followed the first-order kinetics with samples heated at 75°C and above presenting the highest degradation rate and short half-life (5.22 min). The degradation of VE in long-term storage fitted the Weibull model with highest degradation in nanoemulsions stored under light at 40°C. However, VE retained in nanoemulsions after certain period of time might be boosted up when nanoemulsions are stored in the dark. Results showed that the physical stability tests alone are not enough to judge the stability of VE delivery systems, as the encapsulated VE might be lost during processing and storage.

Optimization of the production of solid Witepsol nanoparticles loaded with rosmarinic acid

During the last decade there has been a growing interest in the formulation of new food and nutraceutical products containing compounds with antioxidant activity. Unfortunately, due to their structure, certain compounds such as polyphenols, in particular rosmarinic acid (RA) are not stable and may interact easily with matrices in which they are incorporated. To overcome such limitations, the formulation of loaded polyphenols nanoparticles can offer an efficient solution to protect such compounds. Based on this rationale, the aim of this study was to prepare solid lipid nanoparticles (SLNs) loaded with RA using a hot melt ultrasonication method, where Witepsol H15 was used as lipid and Polysorbate 80 (Tween 80) as surfactant, following a 3(2) fractional factorial design, resulting in the use of 3 different percentages of surfactant (viz. 1, 2 and 3%, v/v) and lipid (0.5, 1.0 and 1.5%, w/v). The stability of the nanoparticles systems were tested during 28 d in aqueous solution stored at refrigeration temperature (ca. 5 °C), tracking the mean particle size of different formulations by photon correlation spectroscopy. To confirm RA entrapment, thermal analyses of the nanoparticles by DSC and FTIR were performed. The association efficiencies percentages (AE%) were determined using HPLC to quantitatively assess the RA in supernatants. Results showed that Witepsol H15 produced nanoparticles with initial mean diameters between 270 and 1000 nm, yet over time, a slight increase occurred, but without occurrence of aggregation. The AE% showed a high percentage of encapsulation (ca. 99%), which reveals low polyphenol releases from SLNs throughout storage time. In general, results showed a successful production of SLNs with properties that can be used to food applications.

Food protein aggregates as vitamin-matrix carriers: impact of processing conditions

We studied the ability of protein aggregates for loading and protection of α-tocopherol, a model of heat- and light-sensitive bioactive compounds. Aqueous dispersions of whey proteins (4.5 wt.%, pH 6.7) in the absence and presence of α-tocopherol (4 wt.%) were prepared using an ultradisperser (10,000 rpm for 10 min and 65 °C), and then submitted to further high-pressure homogenisation (HPH) at 300 or 1200 bar for 12 cycles. Relative to free-vitamin dispersions, increasing HPH conditions in the presence of vitamin led to higher protein denaturation, more tryptophan quenching and wavelength blue-shift (by 10nm), in parallel with increased zeta potential values (by -10 mV), particle sizes (by 50%), and newly formed protein dimers, trimers and high molecular weight aggregates. As a result, the degree of vitamin degradation under increasing HPH and long-term storage was shown to decrease from 66% (ultradisper) to 50%, or to 30% (subject to further treatments at 300 or 1200 bar, respectively).