14,539 research outputs found
Encapsulation of citrus by-product extracts by spray-drying and freeze-drying using combinations of maltodextrin with soybean protein and Îč-carrageenan
The effect of different combinations of maltodextrin (MD) coating agents (MD, MD + soybean protein, and MD + Îč-carrageenan) on the encapsulation of lemon by-product aqueous extracts using freeze-drying and spray-drying were investigated. The total phenolic content (TPC), total flavonoid content (TFC), and ferric ion reducing antioxidant power (FRAP) of the microparticles were evaluated. Freeze-drying with the mixture of MD + soybean protein resulted in the highest retention of TPC, TFC, and FRAP (1.66 ± 0.02 mg GAE/g d.b., 0.43 ± 0.02 mg CE/g d.b., and 3.70 ± 0.05 mM TE/g, respectively). Freeze-drying resulted in microparticles with lower moisture content (MC) and water activity (aw) than those produced by spray-drying. Specifically, the MC and aw of the microparticles produced by freeze-drying ranged from 1.15 to 2.15% and 0.13 to 0.14, respectively, while the MC and aw of the microparticles produced by spray-drying ranged from 6.06% to 6.60% and 0.33 to 0.40, respectively. Scanning electron microscopy revealed that spray-drying resulted in the formation of spherical particles of different sizes regardless of the type of coating agent. Although freeze-drying resulted in microparticles with amorphous glassy shapes, the mixture of MD + soybean protein resulted in the formation of spherical porous particles. X-ray diffraction revealed a low degree of crystallinity for the samples produced by both techniques.</p
The effect of fructose and maltodextrin vs glucose and maltodextrin formulated sports beverages on mountain-bike race performance : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Sport and Exercise Science at Massey University, Wellington, New Zealand
Background: Exogenous carbohydrate improves performance during prolonged high-intensity exercise. When ingested together, fructose and glucose polymers are oxidised at rates 1.5-1.7 higher than isocaloric glucose solutions. As fructose and glucose are transported across the intestine via different mechanisms, the capacity for exogenous-carbohydrate absorption is greater with composite carbohydrate mixtures. Therefore, since the effect of ingesting multi-transportable carbohydrate on field-based performance has to our knowledge not been investigated, we examined their effect on mountain bike race performance. Finishing time was expected to be substantially reduced when multi-transportable carbohydrates were ingested. Method: Ten; male (7) and female (3), mountain bikers aged 32.9 ± 8.7 years, weighing 68.8 ± 9.4 kg and training for at least 8 hours per week and racing regularly participated in a double-blind crossover study. Following a standardised training and diet regimen cyclists completed two Olympic-distance (target winning time of 2h 15m), cross-country mountain bike races during which they ingested either a 11.25% maltodextrin and fructose solution (MF) or an isocaloric, equi-volumetric, isosmotic control solution containing maltodextrin and glucose (MG). Performance times, ratings of perceived exertion, gastrointestinal discomfort and measurements of hydration status were recorded and compared. Data was analysed using appropriate mixed models in SAS. Results: Cyclists were 1.8% (2mins 31s) faster in MF compared to MG (90% confidence interval:±1.8%; 72% likelihood of a substantial benefit) The effect solution composition on the increase in time from the first the final lap (fatigue) was 9.7% (±2.8%) in MF and 10.7% (±2.8%) in MG; which corresponded to a 0.9% reduction (±3.5%; unclear) in the fatigue in MF. Abdominal cramps were reduced by 8.1% in MF relative to MG (±6.6%; likely benefit) and for every 1% change in abdominal cramp rating, lap time increased by 0.14% (±0.10%). There were no clear effects of MF on ratings of perceived exertion and hydration status compared with MG. Conclusion: Cross-country mountain bike race performance was substantially enhanced following ingestion of a maltodextrin and fructose solution. This outcome was related to reduced gastro-intestinal distress supporting the theory that solutions containing multiple-transportable carbohydrates increase the availability of carbohydrate for metabolism. Further investigation with a larger sample size is recommended to establish whether the performance effect is genuinely beneficial or trivial
Storage stability of encapsulated barberry's anthocyanin and its application in jelly formulation
The barberry (Berberis vulgaris) extract which is a rich source of anthocyanin was used for encapsulation with three different wall materials i.e., combination of gum Arabic and maltodextrin (GA+MD), combination of maltodextrin and gelatin (MD+GE) and maltodextrin (MD) by spray drying process. In this context, the storage stability of encapsulated pigments was investigated under four storage temperatures (4, 25, 35 and 42 °C), four relative humidities (20, 30, 40 and 50%) and light illumination until 90 days. All wall materials largely increased the half-life of the encapsulated pigments during storage compared with non-encapsulated anthocyanins. MD+GA showed the highest encapsulation efficiency, lower degradation rate in all temperatures and was found as the most effective wall material in stabilizing the pigments. The encapsulated pigments were utilized in coloring jelly powder as an alternative of synthetic color. Sensory evaluation were run to identify best encapsulated natural color concentration in jelly powder formulation according to acceptability by consumers. A jelly with added 7% encapsulated color had higher scores than the commercial jelly containing synthetic color for all the sensory attributes evaluated. Physicochemical properties of produced jelly including moisture content, hygroscopicity, acidity, ash content and texture were not significantly different with control sample while, syneresis and solubility of the samples prepared with encapsulated color was significantly reduced. © 2016 Elsevier Ltd
Aspartame in conjunction with carbohydrate reduces insulin levels during endurance exercise
Gold OAAs most sport drinks contain some form of non-nutritive sweetener (e.g. aspartame), and with the variation in blood glucose regulation and insulin secretion reportedly associated with aspartame, a further understanding of the effects on insulin and blood glucose regulation during exercise is warranted. Therefore, the aim of this preliminary study was to profile the insulin and blood glucose responses in healthy individuals after aspartame and carbohydrate ingestion during rest and exercise. Each participant completed four trials under the same conditions (45âmin restâ+â60âmin self-paced intense exercise) differing only in their fluid intake: 1) carbohydrate (2% maltodextrin and 5% sucrose (C)); 2) 0.04% aspartame with 2% maltodextrin and 5% sucrose (CA)); 3) water (W); and 4) aspartame (0.04% aspartame with 2% maltodextrin (A)). Insulin levels dropped significantly for CA versus C alone (43%) between pre-exercise and 30âmin, while W and A insulin levels did not differ between these time points. Aspartame with carbohydrate significantly lowered insulin levels during exercise versus carbohydrate alone.Peer Reviewe
Drying/encapsulation of red wine to produce ingredientes for healthy foods
Epidemiological evidence indicates that moderate consumption of red wine reducesthe incidence of coronary disease, atherosclerosis, and platelet aggregation. Wine is very rich in antioxidant compounds because of their phenolic components.However, many people for ethnic, social or religious reasons do not consume wine. Drying/encapsulation of red wine in the presence of adequate carbohydrates leads to water and more than 99% of alcohol removal; a glassy amorphous microstructure is obtained in which the wine's phenolic compounds are entrapped. The resulting product is a free flowing powder which could be used for the polyphenol enrichment of healthy foods and/or drink powders, as well as in the pharmaceutical industry. The wine industry may take advantage of the dried/encapsulated red wine using as a raw material red wines which have littlecommercial value for different reasons; i.e. poor quality due to raw material, unfavourable climatic conditions, or wines that suffered some alteration during the wine making process. Dry encapsulated wine may be a new alternative to red wines that cannot be sold as such for different reasons, and open new opportunities to diversify wine products.Fil: Alvarez Gaona, Izmari Jasel. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Pontificia Universidad CatĂłlica Argentina "Santa MarĂa de los Buenos Aires"; ArgentinaFil: Rocha Parra, Diego Fernando. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Pontificia Universidad CatĂłlica Argentina "Santa MarĂa de los Buenos Aires"; ArgentinaFil: Zamora, MarĂa Clara. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Pontificia Universidad CatĂłlica Argentina "Santa MarĂa de los Buenos Aires"; ArgentinaFil: Chirife, Jorge. Pontificia Universidad CatĂłlica Argentina "Santa MarĂa de los Buenos Aires"; Argentin
Probing the luminal microenvironment of reconstituted epithelial microtissues.
Polymeric microparticles can serve as carriers or sensors to instruct or characterize tissue biology. However, incorporating microparticles into tissues for in vitro assays remains a challenge. We exploit three-dimensional cell-patterning technologies and directed epithelial self-organization to deliver microparticles to the lumen of reconstituted human intestinal microtissues. We also develop a novel pH-sensitive microsensor that can measure the luminal pH of reconstituted epithelial microtissues. These studies offer a novel approach for investigating luminal microenvironments and drug-delivery across epithelial barriers
Microencapsulation optimization of natural anthocyanins with maltodextrin, gum Arabic and gelatin
The barberry (Berberis vulgaris) extract which is a rich source of anthocyanins was used for spray drying encapsulation with three different wall materials, i.e., combination of maltodextrin and gum Arabic (MD + GA), maltodextrin and gelatin (MD + GE), and maltodextrin (MD). Response Surface Methodology (RSM) was applied for optimization of microencapsulation efficiency and physical properties of encapsulated powders considering wall material type as well as different ratios of core to wall materials as independent variables. Physical characteristics of spray-dried powders were investigated by further analyses of moisture content, hygroscopicity, degree of caking, solubility, bulk and absolute density, porosity, flowability and microstructural evaluation of encapsulated powders. Our results indicated that samples produced with MD + GA as wall materials represented the highest process efficiency and best powder quality; the optimum conditions of microencapsulation process for barberry anthocyanins were found to be the wall material content and anthocyanin load of 24.54 and 13.82, respectively. Under such conditions, the microencapsulation efficiency (ME) of anthocyanins could be as high as 92.83. © 2016 Elsevier B.V
Development of novel nanoemulsions as delivery systems : A thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Food Technology at Massey University, New Zealand
Listed in 2016 Dean's List of Exceptional ThesesIn the past decades, emulsions have been widely used as delivery systems for
incorporating bioactive compounds into foods. With the advancing of
nanotechnology, smaller particles in the nanometric range (i.e. nanoemulsions) can
be created with better properties that are more advantageous than conventional
emulsions in terms of their stability to gravitational separation, optical clarity and
better absorption of nutrients in drug delivery (with increased bioavailability). In
particular, emulsification and solvent evaporation method has been used to produce
nanoemulsions with optimum results. However, like conventional emulsions,
protein-stabilised nanoemulsions become unstable when exposed to certain
environmental stresses such as high temperatures, salt addition and extreme pH
changes. Additionally, liquid emulsions are difficult to transport and use in some
food systems while being susceptible to microbial spoilage. To remedy, a dry, stable
emulsion system has to be obtained for their prospective future in food applications.
The objective of this research was to develop nanoemulsions with useful
attributes. The thesis consists of three main parts in which the first part studied the
formation and properties of nanoemulsions using emulsification and solvent
evaporation method; the second part delved into the making of dried nanoemulsion
powders and the third part focused on the structural modifications of nanoemulsions
and encapsulation of a bioactive compound lutein.
To begin, an experimental study to optimise the conditions for producing
nanoemulsions using emulsification and solvent evaporation methodology was
performed under different processing conditions (microfluidisation pressures and
number of passes), organic phase ratios and materials (oil types and emulsifiers). It
was found that smaller oil droplets (around 80 nm in diameter) were achieved when
increasing the microfluidisation pressure up to 12000 psi (80 MPa) for 4 passes at an
organic phase ratio of 10:90. There was a progressive decrease in particle size with
increasing emulsifier concentration up to a 1% (w/w) level for whey protein isolate
(WPI) and lactoferrin but it did not decrease further at higher concentration. On the
other hand, much larger oil droplets were formed in Tween 20 emulsions (120 â 450
nm). The environmental study showed that lactoferrin and Tween 20 emulsions have a better stability to pH changes (pH 2 â 12) and salt addition (0 â 500 mM NaCl or 0
â 90 mM CaCl2) than WPI stabilised nanoemulsions.
After successful preparation of nanoemulsions, liquid nanoemulsions were
converted to dried powders by spray drying or freeze drying. The nanoemulsions
were mixed with different wall materials consisting of maltodextrin alone, trehalose
alone or a 1:1 ratio of maltodextrin and trehalose at 10, 20 or 30% (w/w) solid
concentration. Results showed that the powders containing 20% trehalose have better
powder properties with lower moisture content and water activity, higher bulk
density and good reconstitution in water. The freeze-dried powders showed excellent
wettability and dispersibility in water but lower encapsulation efficiency than spray
dried powders.
In another part of study, nanoemulsions with modified interfacial structure
were used to improve their stability to environmental stresses. The interactions
between WPI and lactoferrin in aqueous solutions were first studied to explore the
feasibility of using these two proteins to form complex interfacial structures at the
droplet surface in the emulsions. Based on ζ-potential and turbidity measurements,
both proteins were shown to interact with each other via electrostatic interactions at
pH values between 6 and 8. The adsorption of protein layers on a gold surface that
mimics the hydrophobic oil surface was also confirmed by a quartz crystal
microbalance with dissipation (QCM-D) study.
Next, a series of bi-layer nanoemulsions at different pH values and lactoferrin
concentrations were prepared so as to determine the best conditions on the overall
emulsion stability. It was shown that the stability of emulsions was dependent on
both pH and lactoferrin concentration. At pH values close to pI of WPI (around pH
5), the nanoemulsions remained unstable regardless of the lactoferrin concentration
used (0.25 â 5% w/w). The nanoemulsions at pH 6 were also unstable at low
concentrations (0.5 â 1% w/w) presumably due to âbridging flocculationâ and
exhibited phase separation. Consequently, a lactoferrin concentration of 3% (w/w)
was used to produce bi-layer nanoemulsions at pH 6. At pH 7 â 10, the bi-layer
nanoemulsions were stable at all lactoferrin concentrations and formed a bi-layer
structure at the interface of droplet.
The formulated nanoemulsions (single layer and bi-layer emulsions) were
subjected to a variety of environmental stresses and in vitro digestion under
simulated gastrointestinal conditions. The emulsion stability to pH changes and salt
addition was improved in the bi-layer emulsions containing WPI and lactoferrin
when compared to the single layer nanoemulsions stabilised by WPI alone. However,
the bi-layer emulsions were more susceptible to destabilisation on heating at
temperatures above 60oC. The in vitro digestion of bi-layer nanoemulsions was
similar to single layer nanoemulsions in which the protein hydrolysis of the
interfacial layers results in extensive droplet flocculation.
In subsequent formulations, lutein was incorporated in the emulsions as a
model of bioactive compound for the application of nanoemulsions as a novel
delivery system. The nanoemulsions well encapsulated lutein in their matrices with
an encapsulation efficiency of 80% and contained small oil droplets (70 â 80 nm).
All the emulsions were physically stable under the tested conditions up to 28 days at
different storage temperatures (5, 20 and 40oC). However, there was a significant
decrease in lutein content during storage especially at higher temperatures due to
oxidative degradation. Nevertheless, the bi-layer nanoemulsions showed a better
stability to lutein degradation. Based on in vitro cell toxicity studies on Caco-2 cells
using MTT assay, both nanoemulsions did not show toxicity as the cell viability was
more than 80% at 10 times or more dilution after 24 hours of incubation. The cellular
uptake of lutein was higher in bi-layer nanoemulsions when compared to single layer
emulsions.
The present work demonstrated that nanoemulsions can be formed using
emulsification and a solvent evaporation method. Dried microcapsules of
nanoemulsions were formed with similar properties as their original nanoemulsions
after reconstitution in water. The nanoemulsions with bi-layer interfacial structure
have better stability to environmental changes than single layer emulsions.
Nanoemulsions did not show more toxicity than their corresponding conventional
emulsions with large oil droplets produced without the use of organic solvent. These
have important implications in the use of nanoemulsions for encapsulation lutein or
other bioactive compounds for applications in foods and beverages
Industrial manufacture of sugar-free chocolates: applicability of alternative sweeteners and carbohydrate polymers as raw materials in product development
Chocolate is dense suspension of solid particles comprising 60-70% sugar and non-fat cocoa solids. Until recently, it was rarely produced as a sugar-free product due to the multi-functional properties of sweetness, bulkiness and textural characteristics that sugar offers to products. Today's consumers are concerned about the high sugar levels, calories and cariogenicity effects in confectionery products, hence increasing popularity of 'light' and 'sugar-free' products. Development of sugar-free chocolates is most challenging since all sugar needs to be replaced. In-depth understanding of the applicability of alternative sweeteners and carbohydrate polymers as ingredients in sugar-free chocolate manufacture would therefore have significant industrial applications
Study of the preparation process and variation of wall components in chia (Salvia hispanica L.) oil microencapsulation
A study of the microencapsulation process of omega-3 rich oil extracted from chia (Salvia hispanica L.) seeds was carried out, which included a comparative analysis of the microcapsules obtained by the spray- and freeze-drying methods using isolated soy proteins and maltodextrin as wall materials at different proportions. Color characterization of the obtained powders was performed and revealed a darker and yellower appearance of the freeze-dried samples compared with the spray-dried ones. Moisture content was measured for each sample and all presented values around 3.5%. The SEM micrographs revealed that spray-dried microcapsules can occur individually or may form clusters or aggregates, with the particles exhibiting a size range varying from 4 to 10 ”m. Encapsulation efficiency was measured, with no significant differences found between drying methods or on varying the proportion of wall components (all samples presented values of aproximately 60%). The oxidative stability of microencapsulated oils under accelerated oxidative conditions revealed protection factors 2-fold higher for all samples. In addition, microencapsulated oil stored under 25 ÂșC revealed lower hydroperoxide values than those of unencapsulated oil throughout the whole storage test. Finally, oil encapsulated in SPI microcapsules also showed lower HPV values than that of the acceptable limit for virgin and cold-pressed vegetable oils (15 meq. O2/kg oil) during the storage test, while unencapsulated oil attained the acceptable limit in 62 days. This result represents an increase in the time of the oil shelf life of between 30 and 48%.Fil: GonzĂĄlez, AgustĂn. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Instituto de Ciencia y TecnologĂa de Alimentos CĂłrdoba. Universidad Nacional de CĂłrdoba. Facultad de Ciencias QuĂmicas. Instituto de Ciencia y TecnologĂa de Alimentos CĂłrdoba; ArgentinaFil: Martinez, Marcela Lilian. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Instituto Multidisciplinario de BiologĂa Vegetal. Universidad Nacional de CĂłrdoba. Facultad de Ciencias Exactas FĂsicas y Naturales. Instituto Multidisciplinario de BiologĂa Vegetal; ArgentinaFil: Paredes, Alejandro Javier. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Unidad de InvestigaciĂłn y Desarrollo en TecnologĂa FarmacĂ©utica. Universidad Nacional de CĂłrdoba. Facultad de Ciencias QuĂmicas. Unidad de InvestigaciĂłn y Desarrollo en TecnologĂa FarmacĂ©utica; ArgentinaFil: Leon, Alberto Edel. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Instituto de Ciencia y TecnologĂa de Alimentos CĂłrdoba. Universidad Nacional de CĂłrdoba. Facultad de Ciencias QuĂmicas. Instituto de Ciencia y TecnologĂa de Alimentos CĂłrdoba; ArgentinaFil: Ribotta, Pablo Daniel. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Instituto de Ciencia y TecnologĂa de Alimentos CĂłrdoba. Universidad Nacional de CĂłrdoba. Facultad de Ciencias QuĂmicas. Instituto de Ciencia y TecnologĂa de Alimentos CĂłrdoba; Argentin
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