Abstract The main goal of this study was to investigate the possibility of encapsulating vitamin D3 (VD3) in Brazil nut (Bertholletia excelsa) oil emulsions stabilized with thermally treated soy protein isolate (SPI). SPI dispersions were analyzed using intrinsic tryptophan fluorescence, surface hydrophobicity and circular dichroism for a better comprehension of the ingredient’s properties. The emulsions produced with SPI dispersions treated at temperatures between 60 and 70 °C showed higher average droplet diameters (10-40 μM) than those treated at 75 and 80 °C. Despite these different droplet diameters, all formulations showed phase separations, requiring the incorporation of xanthan gum (XG) as thickener. Different XG concentrations were, then, tested (0.1 to 0.3% w/v). The formulation with 0.2% (w/v) XG and SPI treated at 75 °C for 15 min showed the highest stability, and, therefore, was used to produce emulsions encapsulating VD3 at two concentrations (120 and 200 μg/mL). After 21 days of storage, the emulsion stabilized with 1.0% (w/v) SPI and 200 µg VD3/mL preserved 97% of the vitamin. Therefore, the results revealed it is possible to obtain an efficient formulation for the encapsulation of VD3 using Brazil nut oil as an oily phase and thermally treated SPI as an emulsifier.

Abstract This study aimed to evaluate the feasibility of producing low-sugar mango jams enriched with curcumin-loaded lipid microparticles (CLM). The jams were incorporated with babacu oil and tristearin lipid microparticles encapsulating curcumin, using tween 80 and span 60 as surfactants. The jams were characterized by physicochemical and sensory tests along 30 days of storage, and the results revealed CLM incorporation had only a small influence on the macroscopic homogeneity and pH of the jams. Up to 4 g/100 g of incorporation of CLM, the color intensity and colorimetric stability of the jams were enhanced. The incorporation of CLM led to the jams to be classified, rheologically, as emulsion filled gels, and the small deformation rheology tests revealed the CLM acted as active fillers. However, the incorporation of 10 g CLM/100 g jam led to a non-reproducibility of the data obtained for frequency sweep experiments. Sensory evaluation (affective tests) indicated a high acceptation of the curcumin enriched mango jams, in terms of flavor, odor, spreadability, texture and color, both at the beginning and end of the storage period of 30 days.

Abstract Tripolyphosphate (TPP)-chitosomes were produced aiming at the encapsulation and conservation of vitamin D3. This hybrid system is made of liposomes, vesicles consisting of phospholipid bilayers, surrounded by chitosan wall ionic-crosslinked with TPP. Chitosan concentrations (2 and 4 mg mL-1) were tested and the vitamin stability in aqueous dispersions monitored for 49 days. The results confim that D3 remained stable throughout the analyzed period (49 days), whereas the non-encapsulated vitamin totally degrades after the second week of storage. The particle diameters ranged from 0.1 to 5 μm with good colloidal stability (+22 to +48 mV), and encapsulation efficiency of 97%. Thermal stability was also improved when using the TPP-chitosomes. The protection performed was attributed to the stable interactions conferred by the phospholipids crosslinking with the chitosan amino groups and a formation of a net of hydrogen bonds established amongst the hydroxyl groups of the interacting compounds as revealed by infrared spectroscopy.

Resumo A microencapsulação é atualmente utilizada pela indústria de alimentos com diferentes propósitos, incluindo a proteção de ingredientes contra fatores, como a oxidação e a volatilização, assim como o aumento da biodisponibilidade e da bioacessibilidade de nutrientes. Este estudo teve por objetivo a encapsulação de betacaroteno em micropartículas lipídicas sólidas estabilizadas com isolado proteico de soro, além de verificar sua integridade sob armazenamento refrigerado e após submissão a diferentes condições de estresse, tais como força iônica, presença de açúcar e tratamentos térmicos. As partículas lipídicas sólidas foram produzidas utilizando estearina de palma, uma gordura vegetal de grau alimentício, a partir de homogeneização de alto cisalhamento. Dentre as diferentes formulações utilizadas durante a produção das partículas lipídicas sólidas, os estudos de caracterização mostraram que uma maior estabilidade foi obtida pelo sistema produzido com 1,25% (m/v) de isolado proteico de soro, 5% (m/v) de estearina de palma e 0,2% (m/v) de goma xantana. Essa formulação foi então escolhida para a posterior produção de partículas lipídicas sólidas encapsulando betacaroteno, etapa na qual foram testadas diferentes concentrações de alfa-tocoferol, a fim de verificar seu potencial antioxidante. Os resultados mostraram que uma adição de alfa-tocoferol nas dispersões de partículas lipídicas sólidas possibilitou um aumento na eficiência de encapsulação dos sistemas, aumentando-a em cerca de 30%, quando comparada à eficiência de encapsulação do sistema no qual o alfa-tocoferol não foi adicionado. Ademais, as dispersões permaneceram estáveis mesmo depois de submetidas a altas concentrações de sal e à escala de temperatura proposta (40 °C a 80 °C), reforçando o potencial de aplicação desses sistemas em condições tipicamente encontradas durante o processamento de alimentos.

Abstract Microencapsulation is currently used by the food industry for different purposes, including the protection of ingredients against factors such as oxidation and volatilization, as well as to increase the bioavailability and bioaccessibility of nutrients. The current study aimed to encapsulate beta-carotene in solid lipid microparticles stabilized with whey protein isolate (WPI), and also investigate their integrity during storage and under stress conditions such as different ionic strengths, sucrose concentrations and thermal treatments. Solid lipid microparticles were produced using palm stearin, a food grade vegetable fat, using a single-step high shear process. Of the different formulations used for lipid microparticle production, characterization studies showed that the greatest stability was obtained with systems produced using 1.25% (w/v) whey protein isolate, 5% (w/v) palm stearin and 0.2% (w/v) xanthan gum. This formulation was applied for the production of beta-carotene-loaded solid lipid microparticles, with different concentrations of alpha-tocopherol, in order to verify its possible antioxidant activity. The results showed that the addition of alpha-tocopherol to the dispersions provided an increase in encapsulation efficiency after 40 days of storage that ranged from 29.4% to 30.8% when compared to the system without it. Furthermore, the solid lipid microparticles remained stable even when submitted to high ionic strength and to heating in the proposed temperature range (40 °C to 80 °C), highlighting their feasible application under typical food processing conditions.

Abstract The feasibility of incorporating beta-carotene-loaded solid lipid microparticles (BCSLM) into vanilla ice creams was investigated, through the physico-chemical characterization and evaluation of sensory acceptability of the products products. The BCSLM were produced with palm stearin as the lipid phase, hydrolyzed soy protein isolate as the surfactant, and xanthan gum as the thickener. The results showed similar values of proximate composition, total soluble solids, pH, and overrun for all formulations. On the other hand, colorimetric evaluations showed that the ice cream produced with partial substitution of artificial additives by BCSLM containing alpha-tocopherol presented a more intense color, while in the product with non-encapsulated beta-carotene, a fast degradation of carotenoid was confirmed, highlighting the importance of the encapsulation techniques. The results of the sensorial analysis of the products were highly satisfactory and showed that the panelists preferred the ice creams produced with BCSLM containing alpha-tocopherol and with partial substitution of artificial additives by BCSLM containing alpha-tocopherol, confirming the feasibility of incorporating BCSLM into ice creams to reduce the application of artificial dyes to the product.

Lipid micro and nanoparticles have been extensively investigated as carriers for hydrophobic bioactives in food systems because they can simultaneously increase the dispersibility of these lipophilic substances and help improve their bioavailability. In this study, lipid microparticles of babacu oil and denatured whey protein isolate were produced, and their ability to protect quercetin against degradation was evaluated over 30 days of storage. Additionally, the lipid microparticles were subjected to the typical stress conditions of food processing (presence of sucrose, salt, and thermal stresses), and their physico-chemical stability was monitored. The data show that the babacu microparticles efficiently avoided the oxidation of quercetin because 85% of the initial amount of the flavonoid was preserved after 30 days. The particles were notably stable up to a temperature of 70 °C for 10 minutes at relatively high concentrations of salt and sucrose. The type of stirring (mechanical or magnetic) also strongly affected the stability of the dispersions.

Solid lipid particles have been investigated by food researchers due to their ability to enhance the incorporation and bioavailability of lipophilic bioactives in aqueous formulations. The objectives of this study were to evaluate the physicochemical stability and digestibility of lipid microparticles produced with tristearin and palm kernel oil. The motivation for conducting this study was the fact that mixing lipids can prevent the expulsion of the bioactive from the lipid core and enhance the digestibility of lipid structures. The lipid microparticles containing different palm kernel oil contents were stable after 60 days of storage according to the particle size and zeta potential data. Their calorimetric behavior indicated that they were composed of a very heterogeneous lipid matrix. Lipid microparticles were stable under various conditions of ionic strength, sugar concentration, temperature, and pH. Digestibility assays indicated no differences in the release of free fatty acids, which was approximately 30% in all analises. The in vitro digestibility tests showed that the amount of palm kernel in the particles did not affect the percentage of lipolysis, probably due to the high amount of surfactants used and/or the solid state of the microparticles.

Solid lipid microparticles were tested as microencapsulation systems for protecting β-carotene from degradation. Blends of long-chain (C18) solid lipids (70% stearic acid) and sunflower oil (30%) were used to produce lipid microparticles encapsulating the carotenoid. Polysorbate 80 (4%) was employed to stabilize the stearic acid microparticles. The concentration of β-carotene was monitored using spectrophotometry, the particle size distribution was measured by laser diffraction, the crystal structure was determined by wide angle X-ray diffraction (WAXD), and the thermal behaviour was characterized by differential scanning calorimetry (DSC) over a period of seven months. All of the systems had an average particle size smaller than 5 µm. To avoid β-carotene oxidation, α-tocopherol was added to the formulations and its action as an oxygen trap was crucial for the antioxidant effect. For stearic-acid microparticles with a-tocopherol, more than 90% of the initial amount of β-carotene was preserved after seven months under refrigerated storage (7-10°C) in the dark. Significant microstructural alterations were detected using WAXD and DSC only in the stearic acid microparticles without alpha-tocopherol. These results seemed promising and suggested that the blends of long-chain solid lipids and liquid lipids were suitable for the production of stable solid lipid microparticles.