Mutual effect of fat and β-carotene on fat crystal network structure and carotenoid bleaching

Morphology and Structure of Solid Lipid Nanoparticles Loaded with High Concentrations of β-Carotene

Solid lipid nanoparticles (SLNs) containing up to 37.5 wt % all-trans β-carotene in the lipid phase are potential water-dispersible food colorants. SLNs have been made by hot-melt high-pressure homogenization with fully hydrogenated sunflower oil and with polysorbate 80 and sunflower lecithin as stabilizers. Atomic force microscopy revealed the SLNs had thin platelet structures most likely derived from the triglyceride crystal β-form, as detected by X-ray diffraction. No indications of crystalline β-carotene were detected. High-performance liquid chromatography analysis showed the extensive isomerization of β-carotene into more than 10 cis isomers, suggesting that it is present as an amorphous mixture. The high β-carotene loadings did not affect the triglyceride crystal structure and the morphology of the SLNs. It is suggested the SLNs consist of a platelet core of crystalline triglyceride surrounded by an amorphous β-carotene-containing layer. The layered structure is suggested to affect the coloring power of the SLNs at β-carotene loadings above 15 wt % of the lipid phase.

Water-in-oil organogel based emulsions as a tool for increasing bioaccessibility and cell permeability of poorly water-soluble nutraceuticals

The use of organogels in food and pharmaceutical sciences has several technical problems related with restricted diffusion of the drugs and lack of a proper gelator molecule. These features are important into the new product design. An alternative to improve technological properties in organogels is the use of emulsions. However, there is a lack of knowledge about the behavior on bioaccessibility and permeability of bioactives loaded into organogel-based emulsions. The objective of the present experimental work was to study the physical properties of organogel-based emulsions made with vegetable oil loaded with three different bioactives (betulin, curcumin and quercetin) and the influence on their bioaccessibility. Organogels were made of canola or coconut oils and myverol as gelator (10% w/w). Water-in-oil emulsions (at 5, 10 and 12.5 wt% of water content) were prepared by mixing the melted proper organogel and water (80 °C) under high shear conditions (20,000 rpm). Micrographs, rheological tests (amplitude, frequency, temperature sweeps and creep-compliance measurements), DSC and particle size analysis were performed to samples. In vitro digestion (oral, gastric and intestinal phase), lipolysis assays, bioaccessibility and permeability tests by cell culture of Caco-2 were made. Organogels of coconut oil have shown poor emulsification properties.

In Vitro Bioaccessibility of Colored Carotenoids in Tomato Derivatives as Affected by Ripeness Stage and the Addition of Different Types of Oil

The simultaneous effect of tomato ripeness stage (mature green, pink, and red-ripe), mechanical processing (dicing and grinding), and oil addition (coconut, sunflower, and olive oils) on the amount and bioaccessible fraction of carotenoids were evaluated. Tomato products obtained from fruits at the most advanced ripeness stage exhibited the greatest values of both concentration and bioaccessible fraction of total carotenoids and lycopene. The type of processing also exerted an important influence on carotenoids content, as well as on its bioaccessibility. Thus, despite the concentration of carotenoids in tomato puree significantly decreased (36% to 59%), their bioaccessibility was greater (up to 2.54-fold increase) than in tomato cubes. Moreover, the addition of oil significantly improved the carotenoid bioaccessibility, especially when olive oil was added, reaching up to 21-fold increase with respect to samples without oil. The results obtained clearly indicate that carotenoids bioaccessibility of tomato derivatives was strongly influenced by the ripeness stage of the fruit, processing and the addition of oil.

PRACTICAL APPLICATION

Bioaccessibility of carotenoids is known to be affected by different factors. This study provides useful information about the synergic effect of different factors affecting the amount and the bioaccessible fraction of carotenoids, especially lycopene, in two common tomato derivatives. The findings of this work may contribute to develop tomato derivatives with high content of bioaccessible carotenoids, leading to the enhancement of their health-promoting properties.

Exploring concentration, surface area and surface chemistry effects of colloidal aggregates on fat crystal networks

An investigation into the effects of concentration, surface area and surface chemistry of silica aggregates on a model fat-structured system.

Ethylcellulose oleogels for lipophilic bioactive delivery – effect of oleogelation on in vitro bioaccessibility and stability of beta-carotene

The in vitro lipolysis and β-carotene (BC) transfer from oil to aqueous phase of canola oil ethylcellulose (EC) oleogels were measured using a static monocompartmental model simulating oral, gastric, and duodenal digestive stages.