Maltodextrin DE Research Articles

Pore-scale study of coupled heat and mass transfer during primary freeze-drying using an irregular pore network model

This study presents a pore network (PN) model with transient heat transfer and quasi-steady transitional vapor transport that is for the first time applied to irregular porous structures that are obtained by reconstruction of X-ray tomography image data. In contrast to previous studies, the irregular pores are not approximated by spheres but implemented in their original shape. Secondly, instead of assuming cylindrical throats as pore connections, the actual distance between pore centers as well as the pore cross sections are used for the computation of the vapor transport coefficient. The control volume elements of the computational model are matched with the cells obtained by Voronoi tessellation. The improvements have clear advantages over former approaches where the reconstructed void space is usually strongly simplified by balls and sticks confined in a regular lattice structure. A freeze-dried sample of maltodextrin DE12 with 20% (w/w) solid content is used for benchmarking the new methodology. Its morphological and thermal properties are determined by the novel PN model. The simulation results of primary freeze-drying (FD) are compared to reference cases in two ways. First, the differences in heat and mass transfer kinetics as compared to regular PNs are emphasized. Secondly, the PN simulation results are confronted with a simple literature model that neglects pore size distribution (PSD) and transient heat transfer. It is shown that already in small domains with relatively narrow PSD, the variation of the mass transfer coefficient affects the computed sublimation fluxes and yields a significant deviation from the simpler literature model. Moreover, it is revealed in this study that the structure has a significant impact on the sublimation front temperature. This is demonstrated by the comparison of FD in the irregular PN to a regular PN with almost identical PSD but different porosity. The development, verification, and benchmarking of the new PN model can be seen as an important step for studies of the structure dependence of FD.

Microencapsulation of honey as flavouring agent in milk powder

Honey is a natural product commonly used in milk powder for flavoring purposes. Currently, honey flavor is added to milk powder in powder form. This study aimed to investigate the effect of spray drying operating conditions on the quantity and quality parameters of the honey powder recovered. The influence of inlet air temperatures, feed flow rates, and type of microencapsulating agents upon the properties of obtained powders was examined. Spray drying of honey with the addition of maltodextrin DE 18 and 12 was carried out at inlet air temperatures of 150, 170, 190℃ and feed flow rates of 330 and 660 mL/h. The properties of the powders obtained were quantified in terms of moisture content (MC), hygroscopicity (HG) and color. Results of experiments showed higher inlet air temperature and lower feed flow rate led to a significant increase (p<0.05) in powder recovery. The total powder recoveries found in this study were between 39.42±2.35% to 71.92±4.17%, which indicates that this process has the potential to be applied on an industrial scale. The decrease in DE of maltodextrin promoted a higher powder recovery. Furthermore, it was found that the browning index increased with the decreasing inlet air temperature and increasing feed flow rate.

Spray-Drying Microencapsulation of Bauhinia ungulata L. var. obtusifolia Aqueous Extract Containing Phenolic Compounds: A Comparative Study Using Different Wall Materials.

Species belonging to the Bauhinia genus, usually known as "pata-de-vaca", are popularly used to treat diabetes. Bauhinia ungulata var. obtusifolia (Ducke) Vaz is among them, of which the leaves are used as a tea for medicinal purposes in the Amazon region. A microencapsulation study of lyophilized aqueous extract from Bauhinia ungulata leaves, which contain phenolic compounds, using five different wall materials (maltodextrin DE 4-7, maltodextrin DE 11-14; β-cyclodextrin; pectin and sodium carboxymethylcellulose) is described in this paper. The microstructure, particle size distribution, thermal behavior, yield, and encapsulation efficiency were investigated and compared using different techniques. Using high-performance liquid chromatography, phenolics, and flavonoids were detected and quantified in the microparticles. The microparticles obtained with a yield and phenolics encapsulation efficiency ranging within 60-83% and 35-57%, respectively, showed a particle size distribution between 1.15 and 5.54 µm, spherical morphology, and a wrinkled surface. Among them, those prepared with sodium carboxymethylcellulose or pectin proved to be the most thermally stable. They had the highest flavonoid content (23.07 and 21.73 mg RUTE/g Extract) and total antioxidant activity by both the DPPH (376.55 and 367.86 µM TEq/g Extract) and ABTS (1085.72 and 1062.32 µM TEq/g Extract) assays. The chromatographic analyses allowed for quantification of the following substances retained by the microparticles, chlorogenic acid (1.74-1.98 mg/g Extract), p-coumaric acid (0.06-0.08 mg/g Extract), rutin (11.2-12.9 mg/g Extract), and isoquercitrin (0.49-0.53 mg/g Extract), compounds which considered to responsible for the antidiabetic property attributed to the species.

Influence of a natural colorant powder from Syzygium cumini L. (skeels) on sensorial and physicochemical properties during storage of a heat-treated flavored fermented milk

This study aimed to evaluate the influence of a powder colorant obtained from a hydroalcoholic extract of jambolan (Syzygium cumini) on the chemical, microbiological, and sensory characteristics of heat-treated flavored fermented milk. The extraction of anthocyanins from the pulp was carried out by maceration with 90% (v/v) ethanol acidified with citric acid. This extract was concentrated (14 to 15% w/v of total solids). Maltodextrin DE 12 was added to obtain 25% (w/v) total solids. Guar gum (0.06% w/w) was added as a stabilizer to whole milk reconstituted with sterilized distilled water (11% w/v total solids). The colorant powder was homogenized at a rate of 1.5 and 2 g per 100 mL of powdered whole milk dissolved in the corresponding amount of water, and sucrose and concentrated strawberry flavoring were added. The natural colorant addition allowed us to obtain a product with pH (4.23-4.75), titratable acidity (1.28-1.47% w/w lactic acid), and color stability, similar to those of yogurt with synthetic colorants. No microbial growth or color changes were detected. The judges did not notice any strange odor, taste, or color. Natural colorants can be a beneficial option for developing healthy and sustainable foods. Keywords: Syzygium cumini; anthocyanins; spray-dried; natural colorant; heat-treated fermented milk.

Influence of a natural colorant powder from Syzygium Cumini L. (Skeels) on sensory and physicochemical properties during storage of a heat-treated flavored fermented milk

This study aimed to evaluate the influence of a powder colorant obtained from a hydroalcoholic extract of jambolan (Syzygium cumini) on the chemical, microbiological, and sensory characteristics of heat-treated flavored fermented milk. The extraction of anthocyanins from the pulp was carried out by maceration with 90% (v/v) ethanol acidified with citric acid. This extract was concentrated (14 to 15% w/v of total solids). Maltodextrin DE 12 was added to obtain 25% (w/v) total solids. Guar gum (0.06% w/w) was added as a stabilizer to whole milk reconstituted with sterilized distilled water (11% w/v total solids). The colorant powder was homogenized at a rate of 1.5 and 2 g per 100 mL of powdered whole milk dissolved in the corresponding amount of water, and sucrose and concentrated strawberry flavoring were added. The natural colorant addition allowed us to obtain a product with pH (4.23-4.75), titratable acidity (1.28-1.47% w/w lactic acid), and color stability, similar to those of yogurt with synthetic colorants. No microbial growth or color changes were detected. The judges did not notice any strange odor, taste, or color. Natural colorants can be a beneficial option for developing healthy and sustainable foods. Keywords: Syzygium cumini; anthocyanins; spray-dried; natural colorant; heat-treated fermented milk.

Effects of native oat starch on vitamin B12 microencapsulation: New perspectives on encapsulants

This study evaluated the effects of native oat starch associated with operating outlet temperature on the microencapsulation of vitamin B12 using the spray drying technique. The composition of the encapsulating material and the operation outlet temperature were evaluated through the central rotational composite design. All the samples were characterized with respect to morphology, crystallinity and chemical composition. The best results were obtained with 82% maltodextrin 10DE, 18% native oat starch, associated with 100 °C for the operation outlet temperature, through the variables: yield (45.12%), L* (51.07 ± 0.39), a* (51.42 ± 0.77), zeta potential (−20.80 ± 0.43 mV), encapsulation efficiency (70.58 ± 0.06%) and wettability (32.14 ± 1.91 min.g − 1). It was concluded that oat starch has a potential for use as an encapsulant, but structural modifications to the starch could promote technological improvements in this application.

Development of lozenges containing extract of Codonopsis javanica (Blume) Hook. f. & Thomson

Codonopsis javanica (Blume) Hook. f. & Thomson, a precious medicinal herb, has demonstrated its therapeutic effects on regulating the immune system, treating cough, dissipating phlegm, lowering blood sugar and protecting the gastric mucosa... This study aimed to develop lozenges containing dry extract of C. javanica (Blume) Hook. f. & Thomson and overcome the disadvantages of ordinary lozenges such as moisture sensitivity, recrystallisation during storage and reducing the consumed energy of users. Several formulations with different excipient ratios and process parameters had been studied. The properties of the lozenges such as moisture content, glass transition temperature (Tg) and hygroscopicity were evaluated. The cause-effect relations between formulation ingredients, process parameters and properties of lozenges were developed, using BCPharSoft OPT software. The optimal placebo formulation consisted of 50% isomalt (w/w) and 15% maltodextrin DE 12 (w/w), and the optimal moulding temperature was 155oC. The optimum percentage of C. javanica (Blume) Hook. f. & Thomson dry extract in the C. javanica (Blume) Hook. f. & Thomson lozenges was 15% (w/w). The chosen lozenges had a moisture content of less than 0.5%, a hygroscopicity level of less than 6% (under experimental conditions at a temperature of 30±2oC, a humidity of 75±5%), and a Tg of 45.8oC. This study could provide useful data for further study on the production of lozenges containing dry extract of C. javanica (Blume) Hook. f. & Thomson.

Single droplet investigation on the levitator to explain the drying kinetics and morphology formation of maltodextrin DE < 3 and DE 21

The investigation of single droplets in the acoustic levitator has been increasingly used in recent years to study their behavior during the drying process. By selectively flowing conditioned air onto the droplets and controlling the ambient conditions, it is possible to observe the drying behavior without contact under conditions similar to those prevailing in spray drying. A CMOS camera is used to continuously measure the change in volume that occurs during drying and an infrared camera is used to measure the surface temperature of the droplets/particles. The data are used to calculate the drying kinetics and the drying parameters with a high degree of accuracy. In addition to the suspensions investigated so far, the drying behavior of the solutions should be examined more closely. Since the drying kinetics of the solutions are complex and depend on the concentration and the material properties, two different maltodextrins (DE <3 and DE 21) and their solutions in different concentrations at different temperatures were investigated. Maltodextrin is a product that dries mainly in the falling rate period. From the results, conclusions were drawn concerning the structural development of the final particle and the average viscosity of the solution during the drying process.

Evaluation of the microencapsulation process of conidia of Trichoderma asperellum by spray drying.

Microencapsulation of microorganisms has been studied to increase product shelf life and stability to enable the application in sustainable agriculture. In this study, the microencapsulation of Trichoderma asperellum conidia by spray drying (SD) was evaluated. The objective was to assess the effect of drying air temperature and wall material (maltodextrin DE20, MD20) concentration on the microencapsulation and to identify the optimum conditions to produce, in high yield, microparticles with low moisture, high conidial viability and conidial survival. Microparticles were characterized in terms of morphology, particle size, and shelf life. A central composite rotatable design (CCRD) was used to evaluate the effect of operating parameters on drying yield (DY), moisture content, conidial viability (CV), and conidial survival (SP). Microencapsulation experiments were carried out under optimum conditions to validate the obtained model. The optimum temperature and MD20/conidia dry weight ratios were 80°C and 1:4.5, respectively, which afforded a drying yield of 63.85 ± 0.86%, moisture content of 4.92 ± 0.07%, conidial viability of 87.10 ± 1.16%, and conidial survival of 85.78 ± 2.88%. Microencapsulation by spray drying using MD20 as wall material extended the viability of conidia stored at 29°C compared with the control. The mathematical models accurately predicted all the variables studied, and the association of the microencapsulation technique using DE20 maltodextrin was able to optimize the process and increase the product's shelf life. It was also concluded that high inlet air temperatures negatively affected conidia survival, especially above 100°C.

Microencapsulation of epiphytic coffee yeasts by spray drying using different wall materials: Implementation in coffee medium

The storage of microorganisms in liquid form is the main drawback of commercializing epiphytic coffee yeasts. This work aimed to evaluate the fermentative performance of microencapsulated yeasts by spray drying in a coffee peel and pulp media (CPM). The yeasts, Saccharomyces cerevisiae CCMA 0543, Torulaspora delbrueckii CCMA 0684, and Meyerozyma caribbica CCMA 1738, were microencapsulated using maltodextrin DE10 (MD), high maltose (MA), and whey powder (WP) as wall materials. A Central Composite Rotational Design (CCRD) was used to investigate the effect of operating parameters on the microcapsules' cell viability, drying yield, and water activity. Yeasts reached cell viability and drying yields above 90 and 50 %, respectively. WP maintained the cell viability of the three yeasts over 90 days of storage at room temperature (25 °C) and was selected as a wall material for the three yeasts. M. caribbica showed to be more sensitive to spray drying and less resistant to storage. Some differences were found in the fermentation of the CPM medium, but the microencapsulated yeasts maintained their biotechnological characteristics. Therefore, the microencapsulation of epiphytic coffee yeasts by spray drying was promising to be used in the coffee fermentation process.

Development of a microencapsulated cocoa (Theobroma cacao) - based product and evaluation of total phenolic compounds and antioxidant capacity

Oxidative stress is associated with the pathogenesis of several chronic diseases. Cocoa is a food rich in polyphenols, with high antioxidant properties, and is an important food in its fight. However, most polyphenols have low solubility, which impairs their biological action. Therefore, encapsulation through the spray drying technique can significantly improve these parameters by generating a protective layer using proteins and polysaccharides. Therefore, the objective of this work was to elaborate a cocoa-based product encapsulated with maltodextrin (CM) or goat milk whey (CW) and to evaluate the total phenolic compounds and their antioxidant capacity, as well as the particle size of the encapsulated product. Cocoa-based products were encapsulated using maltodextrin DE20 or goat whey using a B-290 mini spray dryer (Büchi Labortechnik, Flawil, Switzerland) in a 1:1 weight ratio. Subsequently, the antioxidant capacity was analyzed by the 2,2'-azino-bis (3-ethylbenzoatiazoline-6-sulfonic acid) (ABTS) method and total phenolic compounds using the phenol reagent Folin-Ciocalteu by spectrophotometry, as well as the size of the particle. The CW obtained a higher yield (33.11%) when compared to the CM (24.03%) in the spray dryer. Most of the particles (90%) present in the CM and CS had a size of 21.92 and 21.12 µM, respectively. CW had a higher content of phenolic compounds compared to CM (CM: 536 ± 8.0 vs. CW: 818 ± 77.0 mg GAE/100g dw, p = 0.05). No significant difference was observed in antioxidant capacity between samples (CM: 545 ± 26.0 vs. CW: 478 ± 18.0 µmol TE/100g dw, p = 0.114). The results showed that although CS has a higher content of phenolic compounds, both had the same antioxidant capacity.

Spray-Dried Nipa Palm Vinegar Powder: Production and Evaluation of Physicochemical, Nutritional, Sensory, and Storage Aspects

Nipa palm vinegar (NPV) is a naturally fermented vinegar derived from the nipa palm (Nypa fruticans Wurmb) sap. This work optimized production of spray-dried nipa palm vinegar powder. The influence of the various drier air inlet temperatures (150, 170, and 190 °C) and maltodextrin DE10 carrier concentrations (15 and 20% w/v) in the feed, on the characteristics of the product powder was investigated. Nipa palm vinegar powder (NPVp) was evaluated in terms of the following responses: physicochemical and nutritional properties, sensory acceptability, and storage stability. All processing variables affected the responses. Based on product desirability as the optimization criterion, spray-drying with a hot air inlet temperature of 170 °C with a 15% w/v maltodextrin DE10 in the feed was optimal. The nutritional characteristics of the product made under the above identified optimal conditions were (per 100 g dry product): a calorific value of 366.2 kcal; 1.3 g protein; 88.1 g carbohydrate; 0.96 g fat; 883.9 mg potassium; 12.7 mg vitamin C; and 105 mg gallic acid equivalent (GAE) phenolics content. The product, vacuum-packed and heat-sealed in aluminum laminated polyethylene bags, could be stored at 25 °C for at least 180 days without noticeable loss in quality.

DEVELOPMENT OF THE TECHNOLOGY OF GRANULES WITH THE POLYFRACTION EXTRACT ALFREDIA DROOPING (ALFREDIA CERNUA L.)

Abstract: Alfredia drooping is a source of vegetable raw materials with cerebroprotective, antioxidant and antiradical effects. We obtained a dry polyfraction extract from the lower, petiolate leaves of Alfredia. The purpose of the research is to develop a technology of water-soluble granules based on a polyfraction extract of Alfredia drooping dry for the preparation of a drink. We used polyextract from the leaves of alfredia drooping and water-soluble excipients: maltodextrin DE 12-19, starch sodium glycolate, sodium chloride and sucrose, ethyl alcohol 95% as objects of research. The wet granulation method was used to produce pellets. The technology of the granules consisted in the fact that all the components of the granules (humidity no more than 2%) were mixed, moistened with 95% ethyl alcohol and granulated by pressing through the mesh (holes 2 mm). The granules was dried at a temperature no higher than 30°C to a residual humidity of no more than 2%. The granules were then re-granulated and sieved through a sieve (2 mm holes).In the course of research, the product was evaluated according to the indicators "granulation ability", "disintegration", "uniformity of dosing", "dissolution", "taste". The composition of granules with alfredia polyextract was determined as a result of experiments: polyextract: maltodextrin: sugar: calcium glycerophosphate: starch sodium glycolate: sodium chloride in the ratio 1,41:0,8:1,2:0,16:0,16:0,13 g, respectively. The obtained granules have withstood all tests according to the indicators provided for by GF 14 of the edition: "description", "size of granules", "loss in mass during drying", "disintegration", "uniformity of mass", "microbiological purity". The shelf life for granules with Alfredia extract can be set for a duration of 18 months.

Maltodextrin Moderated Microwave Osmotic Dehydration of Mango Cubes with Finish Air-Drying: Optimum Considerations

The microwave osmotic dehydration of mango cubes under the continuous flow of maltodextrin moderated sucrose solution spray (MWODS) was evaluated based on the quality of the finish air-dried product. Experiments were designed according to a central composite rotatable design to evaluate the effect of maltodextrin moderated sucrose solution [sucrose + maltodextrin (10DE) at a proportion of 85:15] on the finish air-dried product. The process variables were temperature (30 to 70 °C), solute concentration (30 to 70%), contact time (10 to 50 min) and flow rate (0.8 to 3.8 L/min). The optimum processing conditions were determined based on several processes and product-related quality parameters such as moisture loss (ML), solids gain (SG), weight gain, ML/SG, color, texture, rehydration capacity (RHC), bulk density and drying time. The MWODS contact time was the largest significant contributor with respect to most of the parameters, followed by temperature. The optimum values found were an osmotic treatment temperature of 51.7 °C, a solute concentration of 58.5%, a contact time of 30.6 min and a solution flow rate of 1.8 L/min. Finally, these optimized processing conditions were used to compare three different solute mixtures [sucrose only, sucrose + dextrose and sucrose + maltodextrin (10DE) at a ratio of 85:15%] to understand the effect of various solutes on the quality of the finished dried product. Based on the color and textural parameters, along with the RHC, of the finished product, the sucrose + maltodextrin mixture was shown to result in the most desirable quality and the air-dried product without MWODS pretreatment (control) resulted in the least desirable. Overall, the results suggest that the sucrose + maltodextrin combination offered an advantage in terms of quality for the MWODS air-drying of mango cubes.

Prediction of the effect of water on the glass transition temperature of low molecular weight and polysaccharide mixtures

The right storage conditions for food powders containing amorphous carbohydrates are crucial to avoid structural changes. By combining the sorption isotherm and the glass transition temperature (Tg) data for these food powders enables the determination of appropriate moisture and temperature conditions for their storage. In this study, the modified Flory-Huggins free volume theory was utilized to predict the stability diagrams purely from the composition of the powders. The validation of the approach using the literature data of blends of grapefruit, mango and acai powders with various blends of maltodextrin (MD) and gum Arabic. The blends of fructose, glucose individual and in combination with citric acids as well as blackcurrant juice concentrate with MD DE 9–13 were also investigated. The alignment of experimental and predicted data of fruit powders demonstrates that it was possible to predict the relation of the Tg well as a function of the water activity for carbohydrate mixtures.

Flavoring properties that affect the retention of volatile components during encapsulation process

Flavorings are widely used in food and beverage industries and spray drying is the most cost-effective encapsulation technique to deliver stable products. Generally, the same slurry is used to encapsulate both hydrophilic and hydrophobic flavors which led sometimes to lower retention. The same slurry formulation composed by Modified Starch and Maltodextrin 20DE was loaded with 35% of two different flavorings (orange and passion fruit) and, spray dried under the same conditions. The flavorings selected had different octanol/water partition coefficients and their composition affected the emulsion stability. Orange flavoring presented clearly better emulsion stability than passion fruit flavoring, confirmed by size distribution and Turbiscan Stability Index (TSI orange ≪ TSI passion fruit). A key learning from this work is that the best infeed emulsion achieved by the most hydrophobic flavoring, presented the lowest droplet size and yielded in final bigger particle size and the best encapsulation efficiency result (>92%).

Cinnamomum zeylanicum extracts reduce lipid oxidation in broadband anchovy (Anchoviella lepidentostole) minced fish

Minced fish (MF) is an interesting material for development of novel fish products; however, the mechanical deboning process interferes with MF quality, by increasing the lipid oxidation. This study reports the effect of Ceylon cinnamon (Cinnamomum zeylanicum) hydro-ethanolic bark extracts as natural antioxidants on both washed and unwashed MF of broadband anchovy during six months of storage at -18 °C. Spray-dried cinnamon extract (DC) and spray-dried cinnamon extract using maltodextrin 10DE (DCM) as a carrier were evaluated in relation to antioxidant activity in vitro. DC and sodium erythobarte were added to both washed and unwashed MF at 0.25% (w:w), whilst DCM was added at 1.055% (w:w). The DC extract presented higher antioxidant activity in vitro compared to DCM extract. The addition of cinnamon extracts reduced the lipid oxidation in washed and unwashed MF compared with the controls. C. zeylanicum extracts can be used to prevent lipid oxidation in MF during the frozen storage and are alternatives for food industries that seek to meet the demand of consumers increasingly concerned with the consumption of healthy foods.

Optimization of microencapsulation of yellow mombin juice by spray drying using a central composite rotatable design and powder physicochemical properties

Yellow mombin juice was microencapsulated by spray drying. Optimum operating conditions were selected from the outcomes of tests carried out according to a central composite rotatable design, using air inlet temperature (90 to 190 °C), feed flow rate (0.20 to 1.00 L/h) and 15 DE maltodextrin concentration (10 to 30%) as the independent variables, while powder moisture content, water activity, hygroscopicity, total carotenoids retention, and process yield as the responses. As expected, water activity, moisture content and yield of samples were significantly reduced by spray drying. The powder prepared under optimum conditions, whose reconstituted nectar was the most appreciated by panelists in sensory analysis, was partially characterized in terms of physicochemical properties. It exhibited an apparent density of 0.59 g/mL and a solubility of 81.49%. Particles generally occurred in clusters and exhibited spherical shape and smooth surface. The antioxidant activity was shown to be weak to intermediate.

Effects of Enzymatic Liquefaction, Drying Techniques, and Wall Materials on the Physicochemical Properties, Bioactivities, and Morphologies of Zinc-Amaranth (Amaranthus viridis L.) Powders.

The demand for vegetable powder has been escalating considerably due to its various health benefits and higher shelf life compared to fresh green leafy vegetables. Thus, much research emphasised manufacturing vegetable powder at a lower operational cost and higher efficiency while preserving the nutritive values of the vegetables. In this study, zinc- (Zn-) amaranth puree was liquefied with three types of cell wall degrading enzymes (i.e., Viscozyme L, Pectinex Ultra SP-L, and Rapidase PAC) with varying concentrations (0–3% v/w) and incubation time (0.5–24 h) at pH 5 and 45°C before the drying process. The results showed that enzymatic liquefaction using 1% (v/w) of Viscozyme L for 3 h was the optimal procedure for the reduction of the viscosity of the puree. The liquefied puree was then microencapsulated through either spray- or freeze-drying with different wall materials, e.g., 10% of maltodextrin (MD) DE 10, resistant maltodextrin (RMD), N-octenyl succinate anhydride (OSA) starches from waxy maize, HI CAP 100 (HICAP), Capsul (CAP), and gum Arabic (GA). The results showed that all freeze-dried powders generally had higher process yield (except for that encapsulated by HICAP), higher moisture content (but similar water activities), higher retention of total Zn-chlorophyll derivatives, lower hygroscopicity with slab-like particles, larger particle size, and lower bulk density than those of spray-dried powders. In contrast, the spray-dried powders exhibited irregular spherical shapes with relatively high encapsulation efficiency and antioxidant activities. Nonetheless, encapsulation using different wall materials and drying methods had no significant effect on the powder's cohesiveness and flowability.

Optimization of maltodextrin (10DE)—Sucrose moderated microwave osmotic dehydration of mango cubes under continuous flow spray mode (MWODS) conditions

AbstractThe process of microwave osmotic dehydration of mango was optimized under continuous flow medium spray conditions (MWODS) with maltodextrin (10DE) moderated sucrose solutions. Optimization was carried out using a response surface methodology with a central composite rotatable (CCRD) design with three input variables at five levels (temperature, 33°C to 66.7°C; sucrose:maltodextrin ratio from 100:0 to 80:20; and solute concentration, 33 to 66.7%). The response parameters used for optimization were moisture loss (ML), solids gain (SG), weight reduction (WR), ML/SG ratio, color and texture values. For each response, RSM models (p &lt; .05) were developed. As expected, all output variables were responsive to process variables and addition of maltodextrin to sucrose was found to have a significant effect on reducing the SG and increasing ML/SG, and total solute concentration had significant effects on ML, SG and quality parameters. The process was optimized by desirability approach and MWODS at 56°C with total osmotic solute 46% concentration and 84:16 sucrose:maltodextrin proportion had the highest desirability value. Selection of constraints was an influential factor as well.Practical ApplicationsOsmotic dehydration (OD) has many advantages, but is a slow process. Carrying out OD in MW environment accelerates the process, enhances moisture loss (ML) and limits the solids gain (SG). The quality of OD foods is related to ML/SG ratio and the MWOD process enhances ML/SG. This can be further enhanced by incorporating high molecular solutes like maltodextrins. This research optimizes the maltodextrin moderated MWOD process under continuous medium flow conditions. The process offers significant potential for reducing the treatment time (to 30 min) and improve the ML/SG ratio. The resulting product can be finish dried, used as intermediate moisture food or frozen (dehydrofreezing).