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Astaxanthin (AX) is one of the major bioactives that has been found to have strong antioxidant properties. However, AX tends to degrade due to its highly unsaturated structure. To overcome this problem, a Pickering O/W emulsion using nanofibrillated cellulose (NFC) as an emulsifier was investigated. NFC was used because it is renewable, biodegradable, and nontoxic. The 10 wt% O/W emulsions with 0.05 wt% AX were prepared with different concentrations of NFC (0.3–0.7 wt%). After 30 days of storage, droplet size, ζ-potential values, viscosity, encapsulation efficiency (EE), and color were determined. The results show that more stable emulsions are formed with increasing NFC concentrations, which can be attributed to the formulation of the NFC network in the aqueous phase. Notably, the stability of the 0.7 wt% NFC-stabilized emulsion was high, indicating that NFC can improve the emulsion’s stability. Moreover, it was found that fat digestibility and AX bioaccessibility decreased with increasing NFC concentrations, which was due to the limitation of lipase accessibility. In contrast, the stability of AX increased with increasing NFC concentrations, which was due to the formation of an NFC layer that acted as a barrier and prevented the degradation of AX during in vitro digestion. Therefore, high concentrations of NFC are useful for functional foods delivering satiety instead of oil-soluble bioactives.

The pretreatment process is an essential step for nanofibrillated cellulose production as it enhances size reduction efficiency, reduces production cost, and decreases energy consumption. In this study, nanofibrillated cellulose (NFC) was prepared using various pretreatment processes, either chemical (i.e., acid, basic, and bleach) or hydrothermal (i.e., microwave and autoclave), followed by disintegration using high pressure homogenization from oat bran fibers. The obtained NFC were used as an emulsifier to prepare 10% oil-in-water emulsions. The emulsion containing chemically pretreated NFC exhibited the smallest oil droplet diameter (d32) at 3.76 μm, while those containing NFC using other pretreatments exhibited d32 values > 5 μm. The colors of the emulsions were mainly influenced by oil droplet size rather than the color of the fiber itself. Both NFC suspensions and NFC emulsions showed a storage modulus (G′) higher than the loss modulus (G″) without crossing over, indicating gel-like behavior. For emulsion stability, microwave pretreatment effectively minimized gravitational separation, and the creaming indices of all NFC-emulsions were lower than 6% for the entire storage period. In conclusion, chemical pretreatment was an effective method for nanofiber extraction with good emulsion capacity. However, the microwave with bleaching pretreatment was an alternative method for extracting nanofibers and needs further study to improve the efficiency.

In this study, the effect of hydrocolloids with different electrostatic characteristics, namely negatively charged xanthan gum (XG), positively charged chitosan (CH), and non-ionic guar gum (GG), on the physicochemical properties, stability, and lipid digestibility of 10% (w/w) soybean oil-in-water Pickering emulsions stabilized by nanofibrillated cellulose (NFC) was investigated. Addition of XG and CH to the NFC-stabilized emulsions significantly increased the oil droplet sizes and apparent viscosity at high shear rates as compared with the addition of GG. The XG added emulsion showed the lowest rate and extent of creaming, whereas the CH added emulsion gave the highest extent of creaming. The addition of XG and CH led to a more pronounced effect on

Complete nutrition drinks with a low glycemic index (GI) provide nutritional support and prevent hyperglycaemia. The present study identified GI and factors predicting individual glucose response to a new complete nutrition drink. A randomised cross-over controlled trial was conducted in eighteen healthy volunteers (FPG < 100 mg/dl). Complete nutrition drinks containing retrograded starch, glucose solution and white bread were assigned in a random sequence with 14-day wash-out intervals. Plasma glucose and insulin levels were measured from baseline to 180 min after consuming each food. Results show the adjusted GIs of the drink was 48.2 ± 10.4 and 46.7 ± 12.7 with glucose and white bread as the reference, respectively. While the drink has low GI (n = 12) and GI ≥ 55 (n = 6) groups revealed significantly higher baseline insulin in the low GI group (14.86 ± 16.51 μIU/ml v. 4.9 ± 3.4 μIU/ml, P < 0·05). The correlation matrix confirms only two predictive factors for having individual GI r = 0·5, P = 0·03) and HOMA-IR (r = 0·55, P = 0·02). ROC curve reveals fasting insulin above 1.6 μIU/ml and HOMA-IR above 1.05 as the cut-off values. The findings suggest that the complete nutrition drink has a low GI, but there was wide variability in individual responses partly explained by fasting insulin levels and HOMA-IR. Screening for fasting insulin and HOMA-IR may be encouraged to maximise the functional benefit of the drink.

Vitamin D3 was encapsulated in 10% wt soybean oil-in-water (O/W) Pickering emulsions stabilized by either nanofibrillated cellulose (NFC) or whey protein isolate (WPI) at 0.3%, 0.5%, and 0.7% w/w. The vitamin D3 -enriched emulsions were tested for their stability against temperature (30 °C to 90 °C), pH (2 to 8), and ionic strength (0 to 500 mM NaCl). The mean particle diameter (d32 ), ζ-potential, and creaming stability of the oil droplets in the emulsions were measured, as well as their vitamin D3 encapsulation efficiency (EE). After preparation, the oil droplet size (d32 ) of the emulsions stabilized by NFC increased with increasing emulsifier concentration, whereas the droplet size of emulsions stabilized by WPI decreased. NFC provided good stability to the emulsions through a combination of steric and electrostatic repulsion. The EE of vitamin D3 increased with increasing emulsifier concentration. Heating or ionic strength did not significantly (P < 0.05) affect the emulsions properties and EE. On the other hand, the NFC-stabilized emulsions were sensitive to highly acidic conditions (pH 2), with an increase in particle size and decrease in EE. The WPI-stabilized emulsions aggregated around the isoelectric point of the adsorbed proteins (pI ≈ 4.8). Increasing NFC or WPI concentration improved the stability and EE of the emulsions against environmental stresses. NFC-stabilized emulsions had good long-term stability. The results show that NFC can be used as an effective emulsifier for creating vitamin-enriched emulsions with good stability. PRACTICAL APPLICATION: This study can be used to develop more effective encapsulation technologies for fat-soluble vitamins in emulsion-based food products. Encapsulation using nanofibrillated cellulose effectively protected the encapsulated vitamins against environmental stresses which occur in industrial food production (such as pH changes, salt addition, and thermal processing). Moreover, nanofibrillated cellulose extracted from mangosteen rind is a nature-derived emulsifier that is environmental friendly.

In this study, rice starch was modified by different modifications that included debranching (DB), esterification with octenyl succinic anhydride (OSA), debranching followed by OSA modification (DBOS) and OSA modification followed by debranching (OSDB). Following modification, the resistant starch content and emulsifying properties of the modified starches markedly increased in comparison with the native starch with the DBOS starch having the highest resistant starch content and the best emulsifying properties. This can be attributed to its higher degree of OSA substitution resulting in an enhanced amphiphilic character and better emulsion stability. Microstructure, physical stability and rheological properties of oil-in-water emulsions using these modified rice starches were also investigated and it was observed that emulsions stabilized by OSA and DBOS starches exhibited smaller oil droplets, were more stable to creaming and possessed stronger three-dimensional structure when compared with the other modified starch-based emulsions. Since the DBOS starch was found to demonstrate the highest resistant starch content and better emulsifying properties than the other starches, it was then chosen for optimization of its concentration to give the best emulsion characteristics and stability. The emulsions stabilized by the DBOS starch at a concentration of 4% or 5% (w/w) were found to be more stable and very little phase separation was observed after a storage period of 30 days.

Background: Personalized intervention is crucial for effective nutritional advice to prevent diabetes. However, specific characters of the responders to low glycemic index (low GI) diet was unclear. This study was aimed to identify glycemic index and factors affecting response to the low glycemic complete nutrition formula.Method: A randomized cross-over controlled trial was conducted in 18 healthy volunteers (fasting plasma glucose < 100 mg/dL). All participants consumed complete nutrition drink with retrograded starch, glucose solution and white bread (35 g carbohydrate each) in a random sequence with 14-day wash-out intervals. The GI value of complete nutrition drink was determined from area under the curve (AUCi) of postprandial glucose, using glucose solution and white bread as references. Baseline characters of responders (with low GI of complete nutrition drink) and non-responders were compared and correlated to identify factors affecting their responses to the low GI complete nutrition drink. Results: The adjusted GIs for complete nutrition drink with retrograded starch were 48.2 ± 10.4 and 46.7 ± 12.7 when using glucose solution and white bread as the reference food, respectively. Baseline insulin level was the only parameter showing difference between responders and non-responders. The response correlated with baseline insulin (r = 0.4997, p = 0.0347), but was independent of fasting plasma glucose (r = 0.0456, p = 0.8574) and others. Conclusions: In healthy volunteers with normal blood glucose levels, adequate baseline insulin level was the only factor correlated with the response to low glycemic complete nutrition drink. Screening for fasting insulin level may be encouraged for personalized nutrition of low GI diet.Trial registration: TCTR, TCTR20210305001. Registered 4 March 2021 - Retrospectively registered, http://www.thaiclinicaltrials.org/ TCTR20210305001

Contact between upper and lower posterior teeth is crucial for chewing. However, the influence of posterior occluding teeth loss on protein intake and muscle mass was unclear. This cross-sectional study compared consumption frequency of protein food, amount of protein and relevant micronutrient intakes and muscle mass indices among older adults with different Eichner indices (EI) of posterior occluding teeth loss. Ninety Thai healthy adults were divided into three groups (N=30 each) according EI with statistically comparable characters. Food frequency questionnaire, 4-days diet record, and bioelectrical impedance analysis were used for outcome measurement. Our findings suggested that loss of posterior occluding teeth on both sides was associated with less frequent consumption of meat, nut, egg, fish and dairy products, inadequate intakes of protein (< 0.8 g/kg body weight), iron and vitamin B12, and reduced muscle mass indices in older adults. Future large-scale cohort studies are warranted to confirm these findings.

Oil-in-water Pickering emulsions stabilized by nanofibrillated cellulose (NFC) were used to encapsulate and deliver vitamin D3. NFC was extracted from a waste product of the food industry, mangosteen (Garcinia mangostana L.) rind, using dissolution in a hot sodium hydroxide solution, bleaching using hydrogen peroxide, and shearing using a high-pressure homogenizer. This yielded cellulose fibers with a diameter of around 60 nm and a length of several micrometers. Emulsions containing 10% w/w oil (0.01% w/w vitamin D3 and 9.99% w/w soybean oil), 0.10–0.70% w/w NFC as emulsifier, and phosphate buffer (pH 7) were prepared. The effect of NFC on lipid digestion and vitamin bioaccessibility was investigated using a simulated gastrointestinal tract (GIT) model, which included mouth, stomach and small intestine phases. The rate and extent of lipid digestion, as well as the vitamin bioaccessibility, decreased with increasing NFC concentration. Numerous physicochemical phenomena may account for this effect, including the ability of NFC to: act as a physical barrier at the lipid droplet surfaces; to promote droplet flocculation in the gastric phase; and, to increase the viscosity of the aqueous phase. The slight decrease in vitamin D3 bioaccessibility at higher NFC levels, was probably due to the lower level of lipid digestion. Our results indicate that mangosteen fiber can be used to stabilize oil-in-water emulsions, and only has a minor effect on lipid digestion and vitamin bioaccessibility when used at relatively low levels. This information may be useful for the rational design of functional foods from natural waste-products, such as mangosteen rind.

Native rice starch was modified using different methods which included debranching (DB), octenyl succinylation (OSA), debranching followed by octenyl succinylation (DBOS) and octenyl succinylation followed by debranching (OSDB). The effect of different modifications and the impact of modified starch properties (resistant starch content (RS) and degree of substitution (DS)) on the gastrointestinal fate of emulsified lipids are elucidated using an in vitro digestion model that included the mouth, stomach, and small intestine phases in order to understand their functionality for further applications. The effect of the different modified rice starches on the particle size distribution of the lipid droplets, surface charge (ζ-potential), microstructure, lipid digestion (free fatty acid (FFA) release), and starch hydrolysis was also assessed. The OSA-modified starch and DBOS starch-based emulsions were found stable during the mouth phase and were also found to demonstrate lesser flocculation and coalescence in comparison with the other emulsions due to the presence of more OSA groups that provide greater steric hindrance and better protection from the gastrointestinal conditions. Furthermore, the DBOS starch was found to form emulsions that were more resistant to digestion with a degree of FFA release like dietary fibers and a lower extent of starch digestion that can be attributed to their higher resistant starch content (RS). Thus, the DBOS starch-based emulsions were found to be suitable for further applications such as developing functional foods to control satiety or for designing delivery systems for the sustained release of bioactive compounds.

Vitamin D

The application of lycopene, a potent antioxidant, is limited because of its hydrophobic nature and low chemical stability. To overcome this, different delivery systems, i.e. oil-in-water emulsions and alginate beads, have been synthesized in this study using modified rice starch for improving the stability of lycopene. Lycopene solution (in oil) was used as a control. Modified rice starch was used as it is cheap, GRAS, has better adsorption at the oil-water interface and provides higher resistance to the encapsulated lycopene against the harsh environment of the gastrointestinal tract. During storage at different temperatures (4–70 °C) for 15 days, the lycopene degradation rate was found to increase with increasing storage temperature for all delivery systems and with the type of delivery systems in the following order: solution > emulsion > alginate beads. Further, the delivery systems were passed through a simulated gastrointestinal tract (GIT) model to study the extent of lipid digestion and lycopene bioaccessibility. A positive correlation was observed between the rate and extent of lipid digestion and lycopene bioaccessibility. A significantly higher bioaccessibility of lycopene was observed for the emulsions (20.2%) over the beads (15.6%), whereas the chemical stability of lycopene was found to be significantly higher in the alginate beads (35.6%) than in the emulsions (29.5%). Overall, the results obtained suggest that the modified rice starch can be used as an innovative food-grade material for the design of different delivery systems to improve the chemical stability of lycopene and its controlled release in the gastrointestinal tract.

The influence of concentration of microfibrillated cellulose (MFC) extracted from mangosteen ( Garcinia mangostana L.) rind on the properties and stability of 10% w/w soybean oil-in-water (o/w) Pickering emulsions (pH ≈ 7.0) was examined. The MFC concentration in the aqueous phase was varied from 0.05 to 0.70% w/w. The mean droplet size and the color intensity of the emulsions increased with increasing MFC concentration. Microscopic observations revealed that the MFC particles mainly adsorbed at the oil-water interface of the emulsion droplets, whereas the amount of excess non-adsorbing MFC particles present in the continuous aqueous phase increased with increasing MFC concentration. The rheological data provided evidence for network formation in the emulsions with increasing MFC concentration. Such a gel-like behavior was attributed to an inter-droplet network structure and the formation of an MFC network in the continuous phase. All the emulsions were stable to coalescence for a period of 80 days whatever the MFC concentration but the stability to creaming decreased progressively with decreasing MFC concentration. These results have important implication for the rational design and production of particle-stabilized food emulsions.

The impact of biological surfactants (bile salts) on the protein (β-lactoglobulin) corona surrounding gold nanoparticles (200 nm) was studied using a variety of analytical techniques at pH 7: dynamic light scattering (DLS); particle electrophoresis (ζ-potential); UV–visible (UV) spectroscopy; transmission electron microscopy (TEM); and surface-enhanced Raman scattering (SERS). The bile salts adsorbed to the protein-coated nanoparticle surfaces and altered their interfacial composition, charge, and structure. SERS spectra of protein-coated nanoparticles after bile salt addition contained bands from both protein and bile salts, indicating that the protein was not fully displaced by the bile salts. UV, DLS and TEM techniques also indicated that the protein coating was not fully displaced from the nanoparticle surfaces. The impact of bile salts could be described by an orogenic mechanism: mixed interfaces were formed that consisted of islands of aggregated proteins surrounded by a sea of bile salts. This knowledge is useful for understanding the interactions of bile salts with protein-coated colloidal particles, which may be important for controlling the fate of colloidal delivery systems in the human gastrointestinal tract, or the gastrointestinal fate of ingested inorganic nanoparticles.

Herein, we fabricated amphiphilic gold nanoparticles (GNPs) that can self-assemble at oil-water interfaces. We applied those GNPs for in situ SERS detection of emulsifier molecules within the interfacial region of oil in water (O/W) emulsion systems.

Aqueous microfibrillated cellulose (MFC) suspensions were prepared by extraction of ground mangosteen ( Garcinia mangostana L.) rind with hot aqueous sodium hydroxide, bleaching with hydrogen peroxide, and subsequent shearing in a high pressure homogenizer. The cellulose content of the material markedly increased after the alkali and bleaching pre-treatments. The influences of number of passes through the homogenizer on characteristics of the resulting MFC were investigated. Results show that crystallinity index, degree of polymerization, viscoelaticity, and viscosity of the MFC suspensions decreased as the number of homogenization passes increased, indicating that fiber degradation occurred during homogenization. The emulsion stabilizing properties of MFC, on the other hand, were improved when the number of homogenization passes was increased. The oil-in-water emulsions stabilized by MFC (30% w/w soybean oil, 0.7% w/w MFC in aqueous phase, emulsion pH range = 6.8–7.2) obtained at the higher number of homogenization passes exhibited smaller oil droplets, stronger three-dimensional network structures, and more stable to creaming than those stabilized by MFC obtained at the lower number of homogenization passes. The creaming stability of the MFC-stabilized emulsions was reduced at low pH or high salt concentration due to electrostatic screening of the negatively charged MFC particles. Thermal treatment had little influence on the creaming stability of these emulsions. These results should improve understanding of the relationships between processing and characteristics of MFC from a novel lignocellulosic material, i.e. mangosteen rind, and lead to a potential application as an emulsion stabilizer.

In this work, we investigated the conformational changes of a globular protein (β-lactoglobulin, β-lg) coated on the surface of 200 nm gold nanoparticles (GNPs) using a number of analytical techniques: dynamic light scattering (DLS); particle electrophoresis (ζ-potential); localized surface plasmon resonance (LSPR) spectroscopy; transmission electron microscopy (TEM); and surface-enhanced Raman scattering (SERS). The β-lg (pH 3) concentration had a pronounced effect on the aggregation and surface charge of β-lg-coated GNPs. The surface charge of GNPs changed from negative to positive as increasing amounts of β-lg molecule were added, indicating that the globular protein molecules adsorbed to the surfaces of the particles. Extensive particle aggregation occurred when β-lg did not saturate the GNP surfaces, which was attributed to electrostatic bridging flocculation. Modifications in LSPR and SERS spectra after addition of β-lg to the GNP suspensions supported the adsorption of β-lg to the particle surfaces. Moreover, SERS highlighted the importance of a number of specific molecular groups in the binding interaction, and suggested conformational changes of the globular protein after adsorption. This research provides useful information for characterizing and understanding the interactions between globular proteins and colloidal particles.