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Edible oils with physiological functions, such as fish oil and krill oil, which contain polyunsaturated fatty acids (PUFAs), are highly unstable to heat and oxygen. One of the methods for improving the shelf life of these oils is microencapsulation of the oils through spray drying. This mini-review describes the effects of the surface–oil ratio, oil location within the microcapsules, and oil-droplet diameter on the oxidative stability of functional oils in microcapsules prepared through spray drying. The surface–oil ratio, s, can be expressed through the ratio of the average oil-droplet diameter to the average powder diameter, E, by s = 1 − (1 − 2E)3. Additionally, the effects of oil-droplet size and storage temperature on the stability of the encapsulated oil were examined using squalene as a model functional oil. The activation energy Ea of the squalene degradation rate constant of the Avrami equation can be correlated with the average oil-droplet diameter de. The release behavior of the microencapsulated flavors is also discussed because spray drying is also used for the microencapsulation of flavors. The flavor release rate constant of the Avrami equation is related to the oxygen diffusion coefficient of the wall material. [ABSTRACT FROM AUTHOR]

In food products, the encapsulation of flavor in a solid matrix is an important process to overcome the limited properties of flavors, and control flavor release. In this study, allyl sulfide (AS) was encapsulated by spray drying using the modified starch Purity Gum 1773 (PG), an octenylsuccinic acid-modified starch (OSA) as an emulsifier and as a part of wall material. The properties of flavor retention and stability after storage were investigated. PG was more effective in forming emulsified AS spray-dried powder than sodium caseinate. A 94% AS retention rate after spray drying was achieved with 12 wt% PG at 50 wt% solid content. Larger oil droplets and larger particle diameters of spray-dried powder exhibited higher retention of AS under the specified storage conditions. [ABSTRACT FROM AUTHOR]

The release profile of d-limonene and ethyl hexanoate was investigated using a dynamic vapor sorption (DVS) system coupled with gas chromatography. The flavors were encapsulated by spray drying using Saccharomyces cerevisiae cells from which β-glucan had been partially extracted. Relative humidity (RH) was stepped from 20% to 50, 60, 70, and 80% at 30, 40, 50, and 60ºC. The maximum release flux for d-limonene and ethyl hexanoate was around 12 and 28 mg/s∙m2∙g-powder at 80% RH and 60ºC incubation. The Weibull distribution function was well fitted with the experimental data to analyze release kinetics. The release mechanism parameter was greater than 1.0, which indicates a controlled release with initial induction time. The activation energy for ethyl hexanoate (6 kJ/mol) was lower than d-limonene (41 kJ/mol) at 80% RH, which indicates higher affinition of ethyl hexanoate to migrate from the lipid bilayer membrane towards the water phase. [ABSTRACT FROM AUTHOR]

The stability of allyl sulfide, an organosulfur compound present in garlic oil, in its α-, β-, and γ-cyclodextrin inclusion complexes was investigated under various storage conditions. The complexes of cyclodextrins and allyl sulfide were prepared by spray drying. The storage temperature, relative humidity, and initial moisture content of the inclusion complex had different effects on the release rate of allyl sulfide. Allyl sulfide in α-cyclodextrin complexes had a lower release rate than in β- and γ-cyclodextrin complexes at 100 °C and at 50 °C under 6, 40, 54, and 73% relative humidity. The initial moisture content affected only the release rate of allyl sulfide from α-cyclodextrin complexes. The release behavior of allyl sulfide can be correlated with the first-order release rate equation with a normal Gaussian distribution of free energy of activation of release rate constant. The results indicated α-cyclodextrin is a suitable material for controlled release of allyl sulfide. [ABSTRACT FROM AUTHOR]

Encapsulating fish oil by spray drying with an adequate wall material was investigated to determine if stable powders containing emulsified fish-oil-droplets can be formed. In particular, the dextrose equivalent (DE) of maltodextrin (MD) affects the powder structure, surface-oil ratio, and oxidative stability of fish oil. The carrier solution was prepared using MD with different DEs (DE = 11, 19, and 25) and sodium caseinate as the wall material and the emulsifier, respectively. The percentage of microcapsules having a vacuole was 73, 39, and 38% for MD with DE = 11, 19, and 25, respectively. Peroxide values (PVs) were measured for the microcapsules incubated at 60 °C. The microcapsules prepared with MD of DE = 25 and 19 had lower PVs than those prepared with MD of DE = 11. The difference in PV can be ascribed to the difference in the surface-oil ratio of the spray-dried microcapsules. CLSM images for MDs of three DE and vacuole percentage were shown. PV changes of these powders at 60 °C were affected with these powder vacuole structures. [ABSTRACT FROM PUBLISHER]

The encapsulation of bergamot oil by spray drying was investigated by using octenyl succinylated waxy maize starch as wall material and bergamot oil as core. The bergamot oil is majorly composed of d-limonene, linalool and linalyl acetate. High-speed and high-pressure homogenisers were used as major tools of emulsification process. The results indicated that some chemical functional groups were lost during the high-pressure homogenisation. Moreover, larger emulsion droplet size (5-10 μm) was observed when emulsion passed through high-pressure homogeniser. Meanwhile, the saturation of carrier solution before preparing the emulsion was also important to produce the encapsulated flavour powder by spray drying. The optimal value of air inlet temperature at 160 °C to give the highest flavour retention and the lowest surface oil content was observed. Furthermore, the retention of linalool after spray drying was higher than 100%. The transformation of each flavour might occur. [ABSTRACT FROM AUTHOR]

Spray drying is commonly used as a dehydration technique in the pharmaceutical industry for making powdery products directly from liquid. It is also an attractive alternative for obtaining solid pharmaceutical molecules that are traditionally produced by freeze drying. Spray drying is often regarded as a harsh drying method, due to the high temperature of the drying gas. Therefore, some excipients were added to improve the stability in manufacturing process and storage. Emphasis was placed on the encapsulation of proteins by spray drying and crystal transformation method. [ABSTRACT FROM AUTHOR]

Abstract: The crystal transformation of dihydrate trehalose to anhydrous trehalose was investigated using ethanol and a new type of crystal particle with porous structure could be obtained. The specific surface area of the anhydrous crystal transformed at 50°C was 3.3m2/g, with a median pore diameter of 0.21μm, and void volume of 0.22mL/g. The crystal transformation was monitored by measuring the crystal moisture content. The crystal transformation rates could be correlated with the Avrami equation, using the mechanism parameter n =11.5, suggesting that the change of surface area occurred during crystal transformation from dehydrate to anhydrous trehalose. The apparent activation energy of the crystal transformation was 132kJ/mol. [Copyright &y& Elsevier]

The retentions of alcohol dehydrogenase (ADH) activity during drying and storage were investigated at various temperatures and relative humidities for various carbohydrate solutions. The highest retention of ADH activity after drying was obtained for the mixture of trehalose and methyl-ß-cyclodextrin. For a single dried droplet, the effects of humidity on the storage stability of ADH were reversed between the trehalose solution and the blend of trehalose and methyl-ß-cyclodextrin. However, the addition of methyl-ß-cyclodextrin decreased the residual activity of ADH during storage. The carbohydrate matrix structure after drying might influence mainly the storage stability of ADH encapsulated in the mixed carbohydrate of trehalose and methyl-ß-cyclodextrin. [ABSTRACT FROM AUTHOR]

Powdery encapsulation of shiitake flavor was investigated by spray drying with the mixture of cyclodextrin (CD) and maltodextrin (MD). Solubilities of cyclic sulfur compounds except hexathiepane increased with a-CD concentration. Stability constant of lenthionine to a-CD was 5.30 mmol -1 L. The retentions of lenthionine and hexathiepane depended on a type of cyclodextrin. When the encapsulant was a-CD, the addition of MD had a remarkable effect on increasing the flavor retention. This might be due to the high stability constants of shiitake flavors in a-CD. The encapsulant in 3 wt% of a-CD and 27 wt% of MD resulted in the highest retention for lenthionine and other shiitake flavors except hexathiepane. This result suggests that shiitake flavors except hexathiepane have almost same stability constants to a-CD. [ABSTRACT FROM AUTHOR]

Investigates powdery encapsulation of shiitake flavors, extracted from dried shiitake, by spray drying. Increase in flavor retention with an increase in drying air temperature and solid content; Decrease in flavor retention with an increase in dextrose equivalents of maltodextrin; Markedly increased flavor retention due to the use of α-cyclodextrin and maltodextrin in combination as an encapsulant.

The flavor inclusion powder was prepared by spray drying, using the combined encapsulation method of inclusion by β-cyclodextrin (β-CD) and emulsified by gum arabic (GA). d-Limonene and ethyl n-hexanoate were used as model flavors. The application of high pressure by Microfluidizer to the mixture of flavors and β-CD slurry was an effective means of forming inclusion complex. Flavor retention during spray drying under various compositions of the encapsulants was investigated. The flavor retention using the blended encapsulant was increased by adding GA in the encapsulant. The characteristics of release of encapsulated flavor during storage were evaluated at 50°C and 75% of relative humidity. The release rate of flavor in spray-dried powder depended on kinds of the flavors and composition of the encapsulant. The blending MD and β-CD in the feed liquid decreased the release rate of flavors. The rate of release of flavor was analyzed by Avrami's Equation. [ABSTRACT FROM AUTHOR]

Cites a study examining the effects of modified cyclodextrins (CD) hydroxypropyl-β-CD and methyl-β-CD on cDNA-expressed human cytochrome P-450 (CYP) activities. Ability of modified CD to inhibit the activities of CYP2C19 and CYP3A4; Enhancement by CD of the CYP2C9 activity by 140 to 176 percent; Inhibition by methyl-β-CD of CYP1A2 and CYP2D6 at higher concentrations.

Investigates the release characteristics of flavor from spray-dried powder in boiling water and the flavor retention in the rice after cooking. Simulation by Avrami's equation of the behavior of flavor release into the boiling water; Correlation between the retention of d-limonene and ethyl n-hexanoate in cooked rice with the flavor amount of spray-dried powder added.

Hydrocolloid emulsifiers, soy soluble polysaccharide (SSPS), gum arabic (GA), and octenyl succinate starch (OSA-S), were investigated for their ability to produce oil-in-water (O/W) mayonnaise-like emulsions. Xanthan gum (XG) was used as a stabilizer and/or thickener. Oil content above 60%wt. could not be completely emulsified by all three types of emulsifiers. Emulsion separation was observed immediately after preparation. Long term emulsion stability depended on the amount of dispersed phase with higher dispersed phase contents conferring more stability due to a strong network of droplets formed in the system. The formation of Pickering emulsions was confirmed in OSA-S stabilized emulsions. All emulsion systems showed pseudoplastic behavior similar to typical mayonnaise, which increased with an increase in the dispersed phase volume. It was concluded that it is possible to employ hydrocolloid emulsifiers to produce mayonnaise. [ABSTRACT FROM AUTHOR]

The incorporation of relevant amounts of non-adsorbing hydrocolloids to oil-in-water (O/W) emulsions is a suitable alternative to reduce creaming. The effect of incorporating xanthan gum (XG) or guar gum (GG) in soy soluble polysaccharide (SSPS) stabilized oil-in-water (O/W) emulsions was studied. The emulsions contained 6 wt.% of SSPS, 20 wt.% Perilla seed oil (PSO), an omega-3 vegetable oil, and variable amounts of XG or GG ranging from 0.03 to 0.3 wt.%. The presence of minute amounts of XG or GG in fresh emulsions significantly decreased the emulsion droplet size (EDS) although such low concentrations did not provide enough continuous phase viscosity to arrest creaming. Emulsion microstructure indicated the presence of flocculation even at high concentrations of XG or GG caused by a depletion mechanism. All emulsions with XG or GG exhibited pseudoplastic behavior while the control emulsions showed an almost Newtonian behavior. Emulsion droplet polydispersion generally decreased with increase in the continuous phase viscosity indicating the importance of continuous phase viscosity in the dissipation of shear energy throughout the emulsion during homogenization. The characteristics of the emulsions were closely related to the rheological changes of the continuous phase. [ABSTRACT FROM AUTHOR]

Abstract: Soy soluble polysaccharide (SSPS), extracted from the by-product of soy protein isolation, has been widely established as an emulsifier for oil-in-water (O/W) emulsions. Impact of the type of SSPS (i.e. SSPS-L; SSPS-M; and SSPS-H differentiated by their respective extraction conditions) and the type of oil (i.e. Perilla seed oil – PSO; palm kernel oil – PKO; and n-Hexadecane) was examined through analysis of the differences in average droplet diameter, droplet size distribution (DSD) and emulsion rheological properties. Oil/water interfacial tension strongly depended on SSPS type. SSPS-L was the most capable in reducing interfacial tension against PSO, PKO and hexadecane followed by SSPS-M and lastly SSPS-H. Irrespective of oil type, at 20% oil content, SSPS-L and M were better emulsifiers for achieving small droplets due to their high protein content. Both SSPS (types L and M) solutions and their respective emulsions regardless of oil type exhibit Newtonian flow behavior while SSPS-H solution and the respective emulsions show shear-thinning behavior. Emulsion viscosity was influenced by both SSPS and oil types with SSPS-H and hexadecane producing high viscosity emulsions. This paper provides important information on the performance of different types of SSPS against different types of oils which can be used in formulating food and beverage systems. [Copyright &y& Elsevier]

Oil mixtures of medium-chain triglycerides (MCT) and d-limonene in mixing ratios from 10 to 100 wt% were encapsulated in modified starch (wall material) by spray drying to produce oil-rich powders. The oil load (mass ratio of oil mixture to wall material) of the infeed emulsion markedly influenced the properties of the infeed liquid and the characteristics of the resulting powder. The viscosity of the infeed liquid and the particle size of the powder exponentially decreased with increasing oil load, while the emulsion droplet size in the infeed liquid increased. In addition, retention of d-limonene during spray drying also decreased markedly with increasing oil load. Irrespective of the different oil loads and concentrations of the wall material, d-limonene retention was well correlated with the emulsion droplet diameter of the infeed liquid. The encapsulation efficiency of the oil mixture exhibited a maximum value (almost 100%) at an oil load between 0.5 and 1.0, before decreasing at higher oil loads. At an oil load of 2.0, the encapsulation efficiency of d-limonene was reduced to almost zero, while around 40% of the initial MCT was encapsulated in the powder. The increase in oil load also led to increased amounts of surface oil of MCT and d-limonene in the resulting powder due to the increasing emulsion droplet diameter of the infeed liquids. Practical Application: This study proposes the microencapsulation of medium-chain triglycerides under high-oil-load conditions by spray drying. The powders prepared by this process provide significant benefits in terms of rapid energy conversion after consumption without accumulation in the body. Important quality factors of the powder products such as the encapsulation efficiency and the amount of surface oil were examined to understand the optimum process conditions for spray drying. [ABSTRACT FROM AUTHOR]

The thermally stimulated dissociation of the inclusion complex of 1-methylcyclopropene (1-MCP) with α-cyclodextrin (α-CD) in solid state was studied by means of thermogravimetry (TG) and differential scanning calorimetry (DSC). The mass loss of 1-MCP/α-CD inclusion complex occurs in four separated phases with the thermal dissociation of the inclusion complex and release of 1-MCP taking place in the second phase between 90 and 230 °C. The kinetic parameters of the dissociation reaction (the apparent activation energy of dissociation, ED, the reaction order of thermal dissociation, n, and the pre-exponential factor, k0) were evaluated. The dissociation reaction was satisfactorily described by the unimolecular decay law, where the reaction order, n = 1. The effect of the molar ratio of 1-MCP to α-CD (inclusion ratio) in the inclusion complex on the temperature dependence of the dissociation reaction was also studied. The ED decreased with increasing inclusion ratio indicating higher complex stability at lower inclusion ratios. The extrapolation of the ED of the inclusion complexes with different inclusion ratios to 1 mol 1-MCP/mol α-CD yielded the "true" ED of 20.9 ± 2.8 and 18.1 ± 0.2 kJ/mol for TG and DSC, respectively. The "true" ln k0TG and the "true" ln k0DSC were also determined by extrapolation, yielding values of +4.5 ± 1.0 and −0.3 ± 0.3, respectively. [ABSTRACT FROM AUTHOR]

Abstract: The microencapsulation of d-limonene by spray drying was investigated with respect to the effects of emulsion droplet size, powder particle size, as well as to the effects of various kinds of matrices (gum arabic, maltodextrin, and modified starch) on its stability. It was realized by studying release characteristics and oxidative stability during storage. The release and the oxidation decreased deeply with an increase in powder and emulsion particle size for gum arabic and maltodextrin materials. Further, the distributions of emulsion size in the powder showed an increase in the fraction of large emulsion droplets and changed to a bimodal distribution. However, the modified starch HI-CAP 100 showed a higher stability of encapsulated d-limonene than the others. The influence of powder and emulsion size on its encapsulated flavor as well as the change in the emulsion size during storage could not be observed. Industrial Relevance: Spray drying is a common and useful unit operation for microencapsulation of food ingredients. Data on emulsion droplet size and on powder size on product stability provide conflicting results which makes a systematic study regarding these factors highly relevant. The data suggest that an optimal size of flavour powder should be selected for high retention during spray drying, stability during storage and for the ability to control release of flavour. [Copyright &y& Elsevier]

The water sorption process of three types of starch noodles with different cross‐sectional shapes is studied in a temperature range of 30°C–70°C. The process could be expressed by a rate equation based on a linear driving‐force approximation, for all the noodles and at any temperature. The activation energy for water penetration is practically negligible for all the noodles, indicating that there is no energy barrier for water migration. For two noodles with approximately square and rectangular cross‐sections, the equilibrium moisture content shows different degrees of temperature dependence at temperatures higher and lower than the gelatinization temperature of starch. The enthalpy changes for water sorption in the high‐ and low‐temperature regions are greater than 20 kJ mol‐1 and lesser than 10 kJ mol‐1, respectively. It is suggested that the rate‐limiting step of water sorption for gluten‐free noodles was movement of water through the laminar fluid film on the noodle surface. The validity of this suggestion is confirmed by the fact that the water sorption rate increased as the shaking speed during water sorption increased. These findings indicate that increasing the specific surface area is effective in preparing gluten‐free starch noodles with a high water sorption rate. [ABSTRACT FROM AUTHOR]

Yeast cells ( Saccharomyces cerevisiae ), from which β-glucans have been partially extracted, were used to encapsulate flavor inside the lipid bilayer membrane as natural encapsulant. The focus of this study was to investigate the release and stability of flavors ( d -limonene and ethyl hexanoate) encapsulated in yeast cells and maltodextrin (MD) (DE = 19) by spray drying. The release behavior of encapsulated flavors from yeast cells was measured at 40, 60, 80, and 105 °C with different moisture content (0, 50, 100, and 200% of powder). Water affected flavor release from the yeast cells. The release rate constants were correlated using Gaussian distribution of the activation energy of the release rate constants. The release of d -limonene from the spray-dried MD powder showed a different trend than that of yeast cells at various temperatures. The activation energies of the release rate constant for ethyl hexanoate and d -limonene from yeast were 55 and 49 kJ/mol, respectively, under a wet condition. The formation rates of limonene oxide and carvone were slower in yeast than that of MD powder at 30 °C after 2 months. [ABSTRACT FROM AUTHOR]

Based on a two-dimensional percolation theory and an autocatalytic rate expression for oil autoxidation, a statistical model is proposed to estimate the effects of the oil droplet size and the volume fraction of oil within the microcapsule on the oxidation of microencapsulated oil, by means of computational simulations. The model can address both the unique oxidation steps for microencapsulated oil: The rapid progress of oxidation at the early stage of storage and the leveling off of the oxidation after prolonged storage. The simulation also demonstrates that the reduction of the oil droplet size retards the oxidation of microencapsulated oil as well as lowering of the oil fraction within the microcapsule. Practical Applications: A statistical model is proposed to simulate oxidation process of microencapsulated oil. The simulation enable us to reasonably design oil microencapsulation. Based on a two-dimensional percolation theory and an autocatalytic rate expression for oil autoxidation, a statistical model is proposed to estimate the effects of the oil droplet size and the volume fraction of oil within the microcapsule on the oxidation of microencapsulated oil, by means of computational simulations. [ABSTRACT FROM AUTHOR]

The methodology to electrospin polystyrene (PS) fibres functionalised with the inclusion complex between 1-methylcyclopropene (1-MCP) and α-cyclodextrin (α-CD) has been developed successfully. Due to limited availability, α-CD crystals instead of 1-MCP/α-CD complex were suspended in the electrospinning (ES) solutions to investigate the ES process. The ES solutions were characterised in terms of viscosity, conductivity and surface tension. Meanwhile, the fibres were subjected to scanning electron microscopy. The average fibre diameter was proportional to approximately one-sixth power of the capillary number of the ES solution. Viscosity, which was a function of PS concentration and α-CD loading, was the main property that dictated the spin ability of the ES solutions. ES fibres with 1.5–4.4 μm in diameter were produced with 12.5–20.0% (w/w) PS in ES solution and an equal amount of the inclusion complex for PS. In the case of the ES solutions of 20 wt% PS loaded with the inclusion complex from 0 to 100% (w/w) to PS, all the ES solutions were electrospinnable with the average diameter ranging from 3.8 to 4.6 μm. X-ray diffractometry indicated that the α-CD crystals were homogeneously suspended on the fibre mats. Confocal laser scanning microscopy showed that the crystals were suspended on the fibre mats while being coated with a layer of PS. The complex-functionalised fibre was formed from the ES solution of 20% PS and 50% (w/w) inclusion complex with the ES. The release characteristics of 1-methylcyclopropene (1-MCP) from the functionalised fibre and the inclusion complex were investigated real time under linearly ramping humidity conditions at constant temperatures with a home-built humidity regulating system coupled with gas chromatography. The irregular release profiles were successfully modelled and the activation energies of release for the functionalised fibre and inclusion complex were about 128 and 69 kJ/mol, respectively.. [ABSTRACT FROM AUTHOR]

Flavor encapsulation was investigated by spray drying with dried Saccharomyces cerevisiae cells. The yeast cells, Saccharomyces cerevisiae , which were by-products in the production of β-glucan, were used in the encapsulation of d -limonene and ethyl hexanoate. Effects of incubation time, temperature, and spray drying conditions on the encapsulated flavor content after spray drying were investigated. The encapsulation rate constant was 0.69 h −1 for d- limonene and ethyl hexanoate. High contents of both flavors were obtained at an incubation temperature of 40 °C for 4 h and an inlet air temperature of 200 °C for spray drying. Inlet air temperature did not significantly affect encapsulation of flavor content for ethyl hexanoate. Flavor content obtained was 37 wt% for d -limonene and 49 wt% for ethyl hexanoate at an inlet air temperature 200 °C. Thus, yeast could be used as a successful flavor-encapsulant by spray drying. [ABSTRACT FROM AUTHOR]

The effect of the size of oil droplets on the oxidative stability of flaxseed oil in spray-dried powders was investigated. Maltodextrin with a dextrose equivalent of 25 was used as a wall material, and sodium caseinate and transglutaminase-polymerized sodium caseinate were used as emulsifiers. The oxidative stability of flaxseed oil encapsulated in the spray-dried powders was evaluated using lipid oxidation and conductometric determination tests at 105 °C. The powders containing larger oil droplets exhibited higher surface oil content after spray drying, and higher peroxide value and conductivity after storage at 105 °C. Removal of the surface oil from the powders by washing with hexane significantly decreased the conductivity. The results indicated that the surface oil of the spray-dried flaxseed oil powders affected the oxidation stability. Oil droplet size affected significantly the oxidation stability of flaxseed oil in spray-dried powder. [ABSTRACT FROM PUBLISHER]

Inclusion of the two isomers of citral (E-citral andZ-citral), components of lemongrass oil, was investigated within the confines of various cyclodextrin (?-CD,?-CD and?-CD) host molecules. Aqueous complex formation constants forE-citral with?-CD,?-CD and?-CD were determined to be 123, 185, and 204 L/mol, respectively, whereasZ-citral exhibited stronger affinities (157, 206, and 253 L/mol, respectively). The binding trend?-CD > ?-CD > ?-CD is a reflection of the more favorable geometrical accommodation of the citral isomers with increasing cavity size. Encapsulation of lemongrass oil within CDs was undertaken through shaking citral:CD (1:1, 1.5:1, and 2:1 molar ratio) mixtures followed by spray drying. Maximum citral retention occurred at a 1:1 molar ratio with?-CD and?-CD demonstrating the highest levels of totalE-citral andZ-citral retention, respectively. Furthermore, the?-CD complex demonstrated the slowest release rate of all inclusion complex powders. The inclusion between two isomers of citral (E-citral andZ-citral) in lemongrass oil and cyclodextrins by spray drying were studied. [ABSTRACT FROM PUBLISHER]

The aim of this study was to optimize the conditions for subcritical water treatment of krill, as expressed with a single parameter: the severity factor (log R0). Raw krill was treated under subcritical water conditions at various log R0values (1.54–3.75) by varying the treatment temperatures (120–180 °C) and times (0–10 min) in two different sizes of batch-type vessel (10 and 117 mL). The log R0value could efficiently describe changes in various properties of the obtained liquid extracts and solid residues. The most desirable shrimp-like flavor intensity and highest sensory preference were obtained for log R0values of 2.75–3.01. The results also proved that severity factor can be used as a single parameter to control subcritical water treatment conditions in differently sized batch-type vessels to produce shrimp-like flavor extract and residue from krill. Optimization of krill treatment under subcritical water conditions. [ABSTRACT FROM AUTHOR]

Effects of the oil-droplet diameter and emulsification with polymerized sodium caseinate (PNC) on the stability of squalene oil (SQ) retention in spray-dried powder were investigated. The SQ droplet diameter significantly affected the stability of the oil in spray-dried powders. The degradation behavior of SQ powders at 105°C was correlated using the Avrami equation. This oxidation mechanism may occur because of the propagative transfer of radical oxidation between oil-droplet particles. SQ emulsified with 5 wt% PNC and small oil droplets had better oxidative stability when compared with 3 wt% sodium caseinate. [ABSTRACT FROM AUTHOR]

Effect of dextrose equivalent (DE) of maltodextrin (MD) on the reconstituted emulsion stability of emulsified hydrated coconut oil (HCO) in spray-dried powder was investigated. HCO-encapsulated powders were produced with MDs of DE 2, 10, and 25 as wall material and sugar stearic acid esters (SSE) as emulsifier. The reconstituted emulsion from MD of DE 10 was less stable than those from MDs of DE 2 and DE 25. The increase rates of average diameter of reconstituted oil-droplet could be correlated by the zero-order reaction model. By FT-IR and powder X-ray diffraction measurement, spectrum results suggest a stronger interaction between MD of DE 10 and SSE compared to the other two MDs. The interaction between the surfactant and MD is important to select the wall material to form spray-dried powder with a stable reconstituted emulsion. [ABSTRACT FROM AUTHOR]

Comparative analysis of subcritical water (SCW) treatment and ambient pressure boiling one of raw Isada krill was performed for the nutritive, flavour and antiradical properties of krill extracts and residues as well as the molecular mass and odour intensity of the extract. SCW treatment was performed for 10 min in a batch-type vessel in the temperature range of 100-240 °C, using a 1:1 weight ratio of raw krill to water. Higher protein and lipid contents were obtained by SCW treatment relative to boiling. The lipid content of the SCW extracts increased with increasing treatment temperature. Protein was the main component in these extracts, and the highest protein content was achieved by SCW treatment at 200 °C. High-molecular-mass species decomposed under SCW treatment at high temperatures with consequent generation of smaller molecules. The antiradical activity of the SCW extract, determined by DPPH and ABTS assays, increased with increasing treatment temperature. The krill extracts and residues exhibited shrimp-like flavour, and the most desirable flavour was obtained by SCW treatment at 140 °C or 160 °C for 10 min. The treatment would be applicable for the production of seasonings from Isada krill. [ABSTRACT FROM AUTHOR]

The colloidal size and charge of oat protein isolate (OPI) at pH 7.2 and 9.0 with/without transglutaminase (TG) treatment were investigated and related to its surface activity at air–water interface. OPI was prepared from defatted oat flour. It was dispersed in water (pH 7.2), or in buffer (pH 9.0) and the soluble fraction (supernatant after centrifugation at 10 000 × g ) was used for particle size, ζ-potential and dynamic surface tension measurements. Dispersions were found to be electrostatically stable (ζ-potential > −35 mV) with average particle sizes of ∼70 nm at pH 7.2 and ∼30 nm at pH 9.0. When diluted at pH 7.2, dissociation and re-association of the particles occurred resulting in increased polydispersity and increased size, while at pH 9.0 particle size and ζ-potential were unchanged after dilution. Dynamic surface tension measurements revealed slower adsorption dynamics and higher final surface tension values at pH 9.0 than at pH 7.2. TG-treatment of OPI dispersion resulted in formation of inter-molecular covalent linkages and led to decreased average particle size and increased stability against dilution in OPI dispersions at neutral pH. TG-treated proteins showed increased negative charge at pH 7.2 and resulted in higher surface tension values compared to the untreated samples. The topography images of adsorbed or spread layers of OPI at a/w interface revealed that oat globulins were effectively adsorbed and existed as monomeric particles or formed aggregates at the interface depending on pH. [ABSTRACT FROM AUTHOR]

Micellescan be formed from coenzyme Q10(CoQ10) anddipotassium glycyrrhizate (GZK2) by using an inclusioncomplex of CoQ10with γ-cyclodextrin (γ-CD).The mechanism of micelle formation was kinetically investigated. AddingGZK2to a supersaturated solution of the CoQ10/γ-CD inclusion complex led to a linear increase in the solubilityof CoQ10due to the formation of micelles of CoQ10when the molar ratio of GZK2/γ-CD increased to∼1.6, after which the concentration remained constant. Theequilibrium constant Kfor micelle formation was0.68 (−) and the ratio of GZK2to CoQ10was 1. These results suggest that the formation of CoQ10micelles with GZK2might proceed via the displacementof CoQ10by GZK2in the γ-CD cavity followedby the formation of CoQ10micelles. [ABSTRACT FROM AUTHOR]

The polymer-coated inclusion complex powder formation of D-limonene and β-cyclodextrin obtained by spray drying was investigated with respect to the effects of various types of polymer coating agents on the powder particle size and morphology. The addition of the polymer coating agent affected the average particle size, morphology, and internal structures of the spray-dried powders. The average particle diameter of the uncoated spray-dried powders was approximately 5 µm. The powder particle size increased upon the addition of a polymer coating reagent. With the addition of 9 wt% of the polymer coating agent, an average diameter of approximately 80 µm was obtained for the spray-dried powder particles. However, further addition showed a negligible effect on the particle size. Inclusion complex crystals were observed on the surface and inside of the powder particles. [ABSTRACT FROM AUTHOR]

A linearly ramped humidity system coupled with automatic sampling gas chromatography has been developed. The apparatus was adopted to measure the dynamic release flux of D-limonene included in spray-dried β-cyclodextrin (β-CD) and the polymer-coated counterparts under linearly ramped humidity (0.375%/min) at constant temperature (50°C). The release flux profiles of D-limonene were analyzed using a mathematical model based on an extended Arrhenius equation. The activation energy of D-limonene release flux from β-CD was 278 (kJ/mol), which was the highest among the powders and around twice as high as our previous results obtained by the conventional static method. [ABSTRACT FROM AUTHOR]

The ramping method for humidity at constant temperature was used to evaluate the release of D-limonene from spray-dried powder using a handmade dynamic vapor sorption (DVS) instrument. The release fluxes of D-limonene from spray-dried powder at two different liquid feed temperatures, 40 and 80°C, were used to evaluate the flavor release properties of spray-dried powder. The flavor fluxes for 40°C of liquid feed temperature were faster than those for 80°C over the whole humidity range. [ABSTRACT FROM AUTHOR]

Abstract: Dehydration of dihydrate trehalose to its anhydrous form was performed via crystal transformation in a pressure pan with a differential scanning calorimeter using ethanol as the drying medium. The effect of water content of ethanol on the dehydration kinetics was investigated by differential scanning calorimetry (DSC), under two experimental conditions: isothermal and temperature ramping. The data sets collected were analysed by the Avrami equation and the Arrhenius plots for isothermal conditions and by Kissinger’s method for non-isothermal measurements. The Kissinger plots revealed click point temperatures (CPTs) which were dependent on the water content of ethanol. At temperatures below the CPTs, higher activation energies were found, whereas at temperatures above the CPTs, lower activation energies were estimated. The anhydrous trehalose crystals obtained by crystal transformation using ethanol of 0.005–2.5% water content were visually observed as aggregates of nano-sized acicular crystals, which inherited the shapes of the dihydrate trehalose crystals. [Copyright &y& Elsevier]

Abstract: Inclusion complexation reactions between isothiocyanates (ITCs), namely, allyl isothiocyanate (AITC) and phenyl isothiocyanate (PITC), and randomly methylated β-cyclodextrin (RM-β-CD) displayed “AP” type solubility isotherms, indicating continuous increases in the stoichiometry of the inclusion complexes. The complex powders were prepared by spray drying and their heat stability was studied by thermal analysis and heat treatment in paraffin. The solid-state dissociation reactions were satisfactorily described by the unimolecular decay law. The apparent activation energy of dissociation, E D, was determined to be 48 and 58kJ/mol, respectively, for the AITC/RM-β-CD and PITC/RM-β-CD complexes, while the apparent activation energies of decrease of ITCs in paraffin, E P for the pure AITC and PITC, and the corresponding inclusion complexes were 26, 48, 44, and 54kJ/mol, respectively, suggesting volatility suppression and physical stabilisation by inclusion complexation as the plausible mode of stabilisation of the ITCs in paraffin. A compensation effect in the kinetics of depletion of the ITCs in paraffin was established. [Copyright &y& Elsevier]

Abstract: β-Maltose monohydrate was transformed into an anhydrous form by ethanol-mediated method under several temperatures with agitation. A new stable anhydrous form of β-maltose (Mβs) was obtained, as substantiated by the X-ray diffraction patterns. Mβs obtained by this method presented a fine porous structure, resulting in greater specific surface area compared to those of β-maltose monohydrate and anhydrous β-maltose obtained by vacuum drying (Mβh). The crystal transformation presumably consisted of two steps: dehydration reaction from the hydrous to amorphous forms and crystal formation from the amorphous forms to the noble anhydrous form. The kinetics of these reactions were determined by thermal analysis using Jander’s equation and Arrhenius plots. The overall activation energies of the dehydration reaction and the formation of anhydrous maltose were evaluated to be 100 and 90kJ/mol, respectively. [Copyright &y& Elsevier]

Abstract: The dissociation of a crystalline complex of cyclomaltohexaose (α-cyclodextrin) and 1-methylcyclopropene has been studied in response to stepwise rising relative humidity at 50°C using a dynamic vapor sorption instrument. The dissociation of the inclusion complex was monitored with a proton transfer reaction mass spectrometer. The increase in relative humidity generally triggered the complex dissociation. However, the dissociation was greatly retarded at 80% relative humidity, presumably owing to collapse of the crystalline structure. Abrupt dissociation was observed at 90% relative humidity which corresponded to complex dissolution. The changes in powder X-ray diffraction pattern of the inclusion complex during the storage period were also investigated. [ABSTRACT FROM AUTHOR]

S-Adenosyl-L-methionine (SAM) production from Saccharomyces cerevisiae K-9 was comparatively stable under slightly acidic conditions (pH 3.0-5.0) and at low temperature (20-25°C). The kinetics of SAM degradation and 5'-methylthioadenosine (MTA) formation in yeast solution at high temperature (40-60°C) were described by zero-order reactions and the activation energy levels were 104 and 102 kJ/mol, respectively. The optimum retention of SAM after spray drying was obtained at 120°C inlet air temperature. The water content of the powder has a significant effect on the stability of SAM. The SAM yeast powder with trehalose and maltodextrin (dextrose equivalent, DE = 25), used as carrier solids, exhibited higher stability. [ABSTRACT FROM AUTHOR]

The crystal transformation method using ethanol as a dehydration medium is a new method which can create a porous crystal. In this study α-cyclodextrin (α-CD) hexahydrate was transformed by this method and porous ethanol dihydrate crystal was obtained. The pore volume measured was 0.25 mL/g and the median pore diameter was 0.11 μm. Dissolution rate of this crystal was several times higher than that of (α-CD) hexahydrate or anhydrate obtained by drying. [ABSTRACT FROM AUTHOR]

The spray drying conditions affect the retention of flavor compounds in the mimetic rice flavor powder. The wall material is one of the factors of pronounced importance that dictates the flavor retention of the rice flavor powder during spray drying. In this study, we focused on making rice flavor powder by spray drying from mimetic rice flavor oil and the binary mixtures of α-cyclodextrin (α-CD) and highly branched cyclic dextrin (HBCD) as wall material. The composition of α-CD and HBCD influenced the flavor retention and the amount of surface oil on the resultant spray-dried powders. The optimum α-CD content was 67%, at which a spray-dried powder of the highest flavor retention and the least amount of surface oil was obtained. [ABSTRACT FROM AUTHOR]

Abstract: The microencapsulation of l-menthol was studied by spray drying, using gum arabic (GA) and modified starch (CAPSUL, HI-CAP 100) as capsule materials. The results showed a higher retention of l-menthol with the increasing of initial solid concentration. HI-CAP 100, showed a higher retention than the other capsule materials. However, it also showed a higher residue of l-menthol on the surface of powder especially at the high concentration of l-menthol in the feed emulsion. That might be from the interaction between the wall materials and l-menthol which can re-crystallize to form whisker after the spray drying. Furthermore, the release characteristics of l-menthol were also investigated. The release rate increased upon elevation of relative humidity and temperature. The activation energies of the release of l-menthol from GA wall matrices at 75 and 83%RH were 140 and 48 kJ/mol, respectively. Industrial relevance: Controlled release of food constituents is currently receiving highest interest. This study aimed to better understand some of the processing and storage conditions. Decrease in emulsion droplet size led to increased flavor retention during spray drying. Interesting electron-micrographs of the spray dried capsules are provided as well as data on water absorption isotherms and release rate constants vs. storage temperatures. Clear industrially relevent data regarding capsule size, matrix, material, water activity and temperature during storage are provided. [Copyright &y& Elsevier]

The retention of emulsified flavor during spray drying was investigated under various compositions of feed liquid. Drying of the emulsion solution was carried out in a spray dryer, equipped with a centrifugal atomizer. The retention of d-limonene during spray dying was nearly hundred percent independent of the composition of the feed liquid, whereas the retention of ethyl butyrate emulsified by gum arabic (GA) was much lower (0–20%). The retention of ethyl butyrate was markedly dependent on the concentration of maltodextrin and the type of emulsifier, indicating that the stability of emulsion is a controlling factor for flavor retention. The use of mixing emulsifiers, adjusting of density of ethyl butyrate, and the addition of 1% gelatin were quite effective procedures to improve the retention of ethyl butyrate, particularly when emulsified by GA. [ABSTRACT FROM AUTHOR]