Wall Material Concentration Research Articles

Microencapsulation of Lactobacillus reuteri by Emulsion Technique and Evaluation of Microparticle Properties and Bacterial Viability Under Storage, Processing, and Digestive System Conditions

ABSTRACTIn this research, the emulsification method was used to encapsulate Lactobacillus reuteri in microparticles of whey protein concentrate (WPC) at different levels (1%, 2%, and 4%) and gum Arabic (GA) at three levels (0/5%, 1%, and 1/5%) and a constant level of sunflower oil (5%). The results showed that emulsions with higher quantities of wall materials exhibited better encapsulation efficiency (67%/57%) and preservation ability at different temperatures, different pH, and presence of 1% bile salt. During the storage time, the droplet size of the emulsion increased more than two times (from 2.2 to 4.6 μm) and the absolute zeta potential of the optimal emulsion decreased (from −19/63 to −16/76 mV). Encapsulating Lactobacillus reuteri in the stabilized emulsion with the highest concentration of wall material improved the cells' protection during storage. The study also observed a decline in the number of primary encapsulated live cells in the gastrointestinal tract (from 4/32 to 3/58 Log CFU/mL) after 90 days of storage. In the case of the nonencapsulated sample, the initial live population decreased from 2.8 to 1 Log CFU/mL after 90 days of storage. The electron microscope images showed that the emulsions became unstable after 30, 60, and 90 days of storage, but the microbial cells were still visible in the continuous phase. Overall, encapsulating Lactobacillus reuteri using emulsification technique can preserve the probiotics during storage and “in vitro” gastrointestinal digestion.

The complex coacervation of gum Arabic and krill protein isolate and their application for Antarctic krill oil encapsulation

Antarctic krill oil (AKO) possesses potent bioactivities but has limited applications in the food industry due to its poor stability, strong off-flavor, and low bioavailability of contained astaxanthin. In this study, Antarctic krill protein isolate (AKPI) was separated from processing by-product of krill and utilized as a novel wall material via complexing it with gum Arabic (GA) to improve the limitations of AKO. The strong complex coacervation reaction between AKPI and GA was occurred at the pH of 3.8 and the ratioAKPI-to-GA of 3:1, while electrostatic interaction and hydrogen-bond interaction were determined to be the main driving forces of such reaction. The ratiowall-to-core was confirmed as 1:0.75 after comprehensively assessing the effect of AKO content on the various properties of AKPI-GA coacervated microcapsules, while the wall material concentration and pH were optimized at 1 % and 3.8, respectively. The obtained solid AKO microcapsules exhibited the encapsulation efficiency of 80.22 %. AKPI-GA coacervated microcapsules extremely masked the odor of AKO and achieved the controlled-release of AKO in the gastrointestinal tract. Meanwhile, the encapsulated AKO displayed higher astaxanthin retention and oxidative stability compared with non-encapsulated AKO during storage.

A Comparative Study of Encapsulation of β-Carotene via Spray-Drying and Freeze-Drying Techniques Using Pullulan and Whey Protein Isolate as Wall Material.

The encapsulation of β-carotene was investigated using pullulan and whey protein isolate (WPI) as a composite matrix at a weight ratio of 20:80, employing both spray-drying and freeze-drying techniques. The influence of processing parameters such as the concentration of wall material, flow rate, and inlet temperature for SP encapsulants, as well as wall-material concentration for FZ encapsulants, was examined in terms of encapsulation efficiency (EE). The morphology, structural characterization, moisture sorption isotherms, and thermal properties of the resulting encapsulants at optimum conditions were determined. Their stability was investigated under various levels of water activity, temperature conditions, and exposure to UV-Vis irradiation. β-carotene was efficiently encapsulated within SP and FZ structures, resulting in EE of approximately 85% and 70%, respectively. The degradation kinetics of β-carotene in both structures followed a first-order reaction model, with the highest rate constants (0.0128 day-1 for SP and 0.165 day-1 for FZ) occurring at an intermediate water-activity level (aw = 0.53) across all storage temperatures. The photostability tests showed that SP encapsulants extended β-carotene's half-life to 336.02 h, compared with 102.44 h for FZ encapsulants, under UV-Vis irradiation. These findings highlight the potential of SP encapsulants for applications in functional foods, pharmaceuticals, and carotenoid supplements.

Development of chitosan based microencapsulated spray dried powder of tuna fish oil: oil load impact and oxidative stability

Abstract The impact of fish oil concentration on the oxidative stability of microcapsules through the spray drying process using chitosan and maltodextrin as wall material was studied. Emulsions were prepared with different Tuna fish oil (TFO) content (TFO-10%, TFO20%, TF030% TF0-40%) while wall material concentration was kept constant. Microencapsulated powder resulting from emulsion prepared with high fish oil load have high moisture content, wettability, total oil and low encapsulation efficiency, hygroscopicity and bulk tapped density. Oxidative stability was evaluated periodically by placing microcapsules at room temperature. Microcapsules prepared with TFO-10% presented high oxidative stability in terms of peroxide value (2.94±0.04) and anisidine value (1.54±0.02) after 30 days of storage. It was concluded that optimal amounts of fish oil for microencapsulation are 10% and 20% using chitosan and maltodextrin that extended its shelf life during study period.

Stabilization of the Antioxidant Properties in Spray-Dried Microcapsules of Fish and Chia Oil Blends.

Even with healthy foods, there is still a need to protect the functionality during processing. The stabilization and enrichment of fish oil (FO) extracted from fish fillets using solvent extraction might make this healthy oil more available. FO was stabilized by mixing it with chia seed oil (CSO) at 50:50 at room temperature. The antioxidant properties of the blends were evaluated using the total phenolic content (TPC), free radical scavenging activity (DPPH), ferric reducing antioxidant potential (FRAP), and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) activities with FO and CSO as controls. The blends of FO and CSO increased the oxidative stability, while FO was the most susceptible to degradation. The stability and bioactivity of antioxidants against environmental factors were improved by using encapsulation. Response surface methodology (RSM) was used to optimize spray-drying operating conditions for spray-dried microcapsules (SDMs). The independent variables were the inlet air temperature (IAT), which varied from 125 to 185 °C; wall material (WM) concentration, which varied from 5 to 25%; pump speed (PS), which varied from 3 to 7 mL/min; and needle speed (NS), which varied from 3 to 11 s. The results indicated that the maximum antioxidant activity of SDM was obtained at 140 °C IAT, 10% WM, 4 mL/min PS, and 5 s NS, while the minimum value was obtained at 170 °C IAT, 20% WM, 6 mL/min PS, and 9 s NS. The IAT had a significant effect on the antioxidant activities, and the stability of SDMs was increased. These SDMs can be used in the formulation of food matrices due to their therapeutic and nutritional properties.

Inulin-whey protein as efficient vehicle carrier system for chlorophyll: Optimization, characterization, and functional food application.

Natural chlorophylls mostly found in vegetables such as spinach (Spinacia oleracea) could be employed as a possible substitute for synthetic colorants because of their intense green properties. However, the stability of natural chlorophyll is a major challenge to its utilization in the food industry. In this study, spray drying as an encapsulation technique was used to improve the stability of natural chlorophyll. Box-Behnken design was utilized to optimize the spray drying conditions for chlorophyll. Optimum conditions were given as inlet temperature, 132°C; inulin-to-whey protein isolate ratio, 61%:39%; pump rate, 25%, resulting in 92.3% encapsulation efficiency, 69.4% solubility, and -13.5mV zeta potential at a desirability level of 0.901. The particle size, Carr index, bulk and tapped density, polydispersity index, and color showed satisfactory results. Crystallinity, endothermic peak melting temperature, and the enthalpy of chlorophyll-loaded microcapsules increased when compared to the blank microcapsules suggesting decreased hygroscopicity and enhanced thermal stability. In addition, the suitability of fabricated microcapsules using yogurt as a food model was assessed. Yogurt incorporated with chlorophyll-loaded microcapsules showed no significant pH modification with better apparent viscosity than control and sodium copper chlorophyllin (SCC) yogurt after 9 days of refrigerated storage. Based on the studied responses, the spray drying process could be optimized to achieve optimal output and product quality. PRACTICAL APPLICATION: Spray drying is a cheap and convenient approach for microencapsulating bioactive compounds such as chlorophyll. However, the physico-chemical and functional properties of the spray-dried microcapsules are influenced by operating conditions, such as inlet temperature, type and concentration of wall materials, and feed flow rate. Therefore, to maximize and obtain a superior quality of the final product, there is a need to optimize the spray drying process. The Box-Behnken design employed in this study could be utilized as an appropriate technique to design, enhance, and develop process parameters for the fabrication and better retention of the physico-chemical properties of spray-dried chlorophyll microcapsules.

Microencapsulation of enzymatically destabilized virgin coconut oil by spray drying technique: Optimization of process parameters, quality assessment and studies on physico-chemical characteristics of microcapsule

Microencapsulation has gained importance in the recent decade due to its barrier properties and effective release of biochemicals. Virgin coconut oil (VCO) was obtained by enzymatic destabilization with the combination of enzymes papain (0.05 % (w/w)) and cellulase with an efficiency in oil extraction of 72.36 %. The aim of the investigation was microencapsulation of medium-chain fatty acids from coconut milk by spray drying and study the physico-chemical properties of the extracted VCO with morphological studies on the obtained microcapsules. The physicochemical properties (Iodine value = 4.24; Free Fatty Acid= 0.3 ±0.007 %; saponification value = 254 ± 4.16 (KOH/g of oil); peroxide value = 0.71 ±0.014 (meqO2/kg)) of the extracted VCO were analyzed. Medium chain fatty acids (C12: lauric acid, C10: capric acid, C8: caprylic acid) constituted 66 % of the extracted VCO, and Lauric acid (C12:0) was the most abundant medium chain fatty acid (52.7 ± 1.27 %). A five-levelled central composite rotatable design was employed with 20 runs to study the effect of inlet temperature, VCO concentration, and wall material concentration on encapsulation efficiency, oil loading %, moisture content, bulk density, water activity, and total color difference. The optimum process parameters for spray drying of VCO with best encapsulation efficiency (77.77 %), oil loading % (35.12 %), moisture content (4.69 %), bulk density (522.22 kg m-3), water activity (0.37), and total color difference (12.42) were found to be 75:25 (% w/w), proportions of GA (Gum arabic) and MD (Maltodextrin) in the wall material solution concentration, 25 (% w/w), VCO concentration and inlet air temperature of 160℃. The obtained VCO microparticle was analyzed for its powder characteristics with Carr index (2.27-11.50) and Hausner ratio (1.02-1.13), indicating good flowability. The spherical shape and smooth exterior surface of the microparticles, revealed by SEM pictures, ensured the protection and retention of VCO inside the microcapsules.

Study on preparation and properties of Camellia oleifera seed oil microcapsules by complex coacervation and spray drying

The Camellia oleifera seed oil is popular among consumers for its high nutritional value, but the instability of lipid oxidation limits its wide application in practical situations. In this study, we used whey protein and three wall materials to make microcapsules by composite co-composition and spray-drying. The results showed that the best embedded method was the combination of whey protein and chitosan. The preparation process of the combination with whey protein and chitosan was selected as follows: wall material concentration 2.50%:1%, wall material ratio 3:1, pH 3.8, core-wall ratio 1:1, the selected homogenization time 3 min, and the efficiency 81.37 ± 0.29%. The results showed that the main volatile components in the microcapsules of Camellia oleifera seed oil were aldehydes, and the relative content of nonanal was 31.65%. The Fourier transform infrared results showed that this carrier of Camellia oleifera seed oil without changing its properties, and the thermogravimetric results showed that the microcapsules had better thermal stability. Moreover, the in vitro digestion results showed that the microcapsules could delay the digestion of Camellia oleifera oil in gastric juice. The camellia seed oil microcapsules in this study provide a new application for Camellia oleifera seed oil in many fields.

Optimization of the encapsulation process of Cupuassu (Theobroma grandiflorum) pulp by spray drying as an alternative for the valorization of Amazonian fruits

Cupuassu (Theobroma grandiflorum) is an Amazonian fruit with high nutritional value and considerable antioxidant activity mainly due to phenolics and ascorbic acid. To preserve those compounds and their activity, the pulp of cupuassu was spray dried using inulin/maltodextrin mixtures as wall material. The process was optimized using response surface methodology (RSM) based on a central composite design, with inlet temperature (X1), inulin concentration in the wall material (X2) and wall material concentration (X3) as independent variables. Yield, moisture, water activity (aw), hygroscopicity, water solubility index (WSI), and ascorbic acid (AA) and phenolic (PC) encapsulation efficiency were studied. The fitted results (mostly second-order equations) enabled us to determine the optimal conditions of inlet temperature (185 °C), inulin concentration (44%), and wall material concentration (35%) with low predictive error and high desirability (close to 1.0). The microencapsulates with a sphere of diameter 2.16 ± 1.32 μm had a smooth surface and a low degree of agglomeration. Under simulated intestinal fluid conditions, 76.7% of ascorbic acid was released. These results suggest the great potential of the obtained cupuassu microencapsulates as a strategy for Amazonian fruit valorization.

Preparation of β-ionone microcapsules by gelatin/pectin complex coacervation

β-ionone has a unique violet odor and good biological activity, which is an essential fragrance component and potential anticancer drug. In this paper, β-ionone was encapsulated using complex coacervation of gelatin and pectin, followed by cross-linking with glutaraldehyde. The pH value, wall material concentration, core-wall ratio, homogenization conditions, and curing agent content were investigated in the single-factor experiments. For example, the encapsulation efficiency increased with the homogenization speed, which reached a relatively high value at 13000 r/min for 5 min. The gelatin/pectin ratio (3:1, w/w) and pH value (4.23) significantly affected the size, shape, and encapsulation efficiency of the microcapsule. The fluorescence microscope and SEM were used to characterize the morphology of the microcapsules, in which the microcapsule has a stable morphology, uniform size, and spherical multinuclear structure. FTIR measurements confirmed the electrostatic interactions between gelatin and pectin during complex coacervation. Thermogravimetric analysis (TGA) revealed that the microcapsules could maintain good thermal stability over 260 °C. The release rate of β-ionone microcapsule was only 20.6 % after 30 days at the low temperature of 4 °C. These findings provide an effective carrier to deliver flavors like β-ionone and could be useful in the fields of daily chemicals and textiles.

Preparation and properties of n-hexane microcapsules by complex coacervation

In order to improve the encapsulation efficiency of low density core material microcapsules, the complex condensation method was used to prepare microcapsules with n-hexane as the core material and gelatin and Arabic gum as the wall material.For n-hexane with low density, the influence of wall material concentration on microcapsule morphology, the influence of core wall ratio on microcapsule wall thickness, the influence of emulsifying speed on emulsifying effect, the influence of crosslinking curing reaction pH on thermal stability, and the influence of complex coacervation pH on turbidity were studied by turbidimetric titration. The experimental results show that: For the low-density core microcapsules, the spherical multi-core microcapsules prepared are regular in capsule shape, but the encapsulation efficiency is lower than 30%, and the waste of wall material is serious. The wall material concentration is 2%, the core-to-wall ratio is 3:1, the emulsification speed is 10000 r/min, the pH of complex oacervation is 4.0, and the pH of crosslinking curing reaction is 10.0. The microcapsules prepared on this basis are monocytic and irregular. Although the shape and phase of the capsules are irregular, they have good encapsulation effect, with the yield up to 71.86% and encapsulation efficiency up to 70%. Meanwhile, they have good thermal stability.

Preparation and characterization of glucoamylase microcapsules prepared by W/O/W type complex coacervation freeze drying.

Glucoamylase was often used in the brewing industry but was unstable to several environmental factors and reacted quickly to produce fermentable sugar, which limited its applications. Microencapsulation could effectively overcome the drawbacks. This study evaluated the feasibility of the preparation of glucoamylase microcapsules (GM) using W/O/W complex coacervation-freeze-drying method. The parameters of the microcapsules were optimized by the response surface optimization design: core-wall ratio at 1:1, wall-material concentration at 8%, and coagulation time for 20min. Under current condition, the final microencapsulation efficiency reached 85.64±1.60%. Glucoamylase could be slowly released for more than 96h in the liquid state, and could react slowly for more than 336h in the solid state. The optimized GM were incubated for 1h, and the relative enzyme activity was better than that of free glucoamylase under high temperature conditions. The water capacity, solubility, morphology, differential scanning calorimetry, and Fourier transform infrared spectroscopy were conducted. Glucoamylase exhibited good sustained release characteristics. The microcapsules were more resistant to environmental stimuli and showed stronger robustness after optimization. PRACTICAL APPLICATION: Saccharification enzymes are often used in the winemaking industry, and direct addition will cause the fermentation process to heat up too quickly, resulting in the inactivation of microorganisms and saccharification enzymes, affecting the efficiency of saccharification enzymes. Therefore, microcapsules are used to encapsulate the saccharification enzyme, and its efficacy is slowly released for a long time during the fermentation process.

Development of an Encapsulation Method for Trapping the Active Materials from Sour Cherry Biowaste in Alginate Microcapsules

This study aims to contribute to those valorization approaches for the recovery process of high-value-added substances in environmentally friendly ways. In this study, one of the most consumed juice products was selected for providing waste byproducts (peel). Sour cherry peels were subjected to automatic solvent extraction using a GRAS solvent (aqueous 80% ethanol, v/v). Then, encapsulation for the preservation of the related extract was performed by ionic gelation in alginate beads. The process conditions (gelling medium concentration, wall material concentration, and hardening time) were optimized by a Box-Behnken design (statistical experimental design approach). An almost 80% encapsulation efficiency was achieved under the proposed method (7.8% CaCI2, 1.3% alginate, and 26 min). The inhibition effect of the produced capsules against DPPH (2,2-diphenyl-1-picrylhydrazil) radicals also shows that the current products might represent potential alternative natural antioxidants for food formulations. The morphological properties were also measured.

Stability and antioxidant activity of chitosan/β-Lactoglobulin on anthocyanins from Aronia melanocarpa

The anthocyanins from Aronia melanocarpa (AAM) have captured the interest of researchers because of their potential health-related functionalities. However, the application of anthocyanins is limited by their poor stability. Therefore, to improve their physical and oxidative stability, single factor and orthogonal tests were designed to optimize the preparation conditions of chitosan/β-Lactoglobulin encapsulating AAM (M-AAM) and evaluated the nanocapsules in terms of their physicochemical characteristics, storage stability, and the oxidant stability during in vitro simulated digestion. Results showed that the optimal synthesis conditions for M-AAM were determined to be as follows: pH of 6, chitosan/β-lactoglobulin ratio of 1:5 (g/g), core-to-wall ratio of 1:5 (g/g), wall material concentration of 1.25%, and stirring time for 1.0 h. Under these conditions, the embedding rate of AAM reached 77.36%. AAM and M-AAM were suitable for storage at 4 °C and in darkness, chitosan/β-Lactoglobulin nanoparticles significantly improved anthocyanin retention rate in different storage conditions. Moreover, encapsulation protected AAM from gastric digestion and prolonged the retention time of AAM in the intestinal tract. Furthermore, the antioxidant effect of M-AAM improved significantly after in vitro simulated digestion. Therefore, the stability and antioxidant properties of AAM were improved via encapsulation within chitosan/β-Lactoglobulin nanocapsules.

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.

Effects of Chitosan-Coated Microdiet on Dietary Physical Properties, Growth Performance, Digestive Enzyme Activities, Antioxidant Capacity, and Inflammation Response of Large Yellow Croaker (Larimichthys crocea) Larvae.

A 30-day feeding trial was designed to investigate the physical properties of chitosan-coated microdiet (CCD) and the effect of CCD on survival, growth performance, activities of digestive enzymes, intestinal development, antioxidant capacity, and inflammatory response of large yellow croaker larvae (initial weight: 3.81 ± 0.20 mg). Four isonitrogenous (50% crude protein) and isolipidic (20% crude lipid) microdiets were prepared with different concentrations of chitosan wall material by spray drying method (0.00%, 0.30%, 0.60%, and 0.90%, weight (chitosan) : volume (acetic acid)). Results showed that the lipid encapsulation efficiency (control: 60.52%, Diet1: 84.63%, Diet2: 88.06%, Diet3: 88.65%) and nitrogen retention efficiency (control: 63.76%, Diet1: 76.14%, Diet2: 79.52%, Diet3: 84.68%) correlated positively with the concentration of wall material (P < 0.05). Furthermore, the loss rate of CCD was significantly lower than the uncoated diet. Larvae fed the diet with 0.60% CCD had significantly higher specific growth rate (13.52 and 9.95%/day) and survival rate (14.73 and 12.58%) compared to the control group (P < 0.05). Larvae fed the diet with 0.30% CCD had significantly higher trypsin activity in pancreatic segments than the control group (4.47 and 3.05 U/mg protein) (P < 0.05). Larvae fed the diet with 0.60% CCD had significantly higher activity of leucine aminopeptidase (7.29 and 4.77 mU/mg protein) and alkaline phosphatase (83.37 and 46.09 U/mg protein) in the brush border membrane than those of the control group (P < 0.05). The intestinal epithelial proliferation- and differentiation-related factors (zo-1, zo-2, and pcna) in larvae fed the diet with 0.30% CCD had higher expression than those of the control group (P < 0.05). When the concentration of wall material reached 0.90%, the larvae had significantly higher superoxide dismutase activity than that of the control group (27.27 and 13.72 U/mg protein) (P < 0.05). Meanwhile, malondialdehyde contents were significantly lower in larvae fed the diet with 0.90% CCD than that of the control group (8.79 and 6.79 nmol/mg protein) (P < 0.05). 0.30%~0.60% CCD significantly increased the activity of total nitric oxide synthase (2.31, 2.60, and 2.05 mU/mg protein) and inducible nitric oxide synthase (1.91, 2.01, and 1.63 mU/mg protein) and had significantly higher transcriptional levels of inflammatory factor genes (il-1β, tnf-α, and il-6) than those of the control group (P < 0.05). The results indicated chitosan-coated microdiet had great potential in feeding large yellow croaker larvae in addition to reducing nutrition loss.

Microencapsulation of corn mint (Mentha arvensis L.) essential oil using spraydrying technology

The objective of this study was to investigate the factors affecting the microencapsulation process of corn mint (Mentha arvensis L.) essential oil using the spray drying method. Different impact factors were evaluated including concentration of maltodextrin (20-30%), concentration of essential oils (0.5-2.0%), homogenization method, inlet temperature (130-150°C), and feed flow rate (4 -10 mL/min). The suitable conditions were the wall material concentration of 25% (w/ w), essential oil concentration of 1.5% (w/w), using rotor-stator blend, the temperature of 140°C, and feed flow rate of 8 mL/min. The microencapsulation efficiency, the microencapsulation yield and spray-drying yield were 98.9%, 68.6%, and 84.8%, respectively.

Microencapsulation of the green coffee waste extract with high antioxidant activity by spray‐drying

Currently, green coffee beans (GCB) are used in the food industry for oil extraction. 85% of which is discarded as a residue termed. Green coffee waste extract (GCWE). Which contains antioxidant compounds that have beneficial health effects. Antioxidant compounds are easily degraded and sensitive to various environmental conditions which can be combatted. Through microencapsulation, specifically through spray drying, which is widely used owing to its simplicity and low operating costs. The aim of this study was to evaluate the optimal concentration of wall materials for encapsulating GCWE. The characterization of GCWE by high-performance thin-layer chromatography (HPTLC) indicated that the extract was rich in chlorogenic acid with 21.78 mg/g representing 31.71% of the total phenols. Thereafter, a composite central design was conducted to determine the optimal concentrations of the wall materials (fructans and gum arabic); the best concentrations were 3% fructans and 2% gum arabic. The encapsulation process produced microcapsules with a 94.36% encapsulate efficiency and a 27.45% (18.86 mg/g) concentration of chlorogenic acid. In conclusion, we evaluated the effect of wall material concentration and determined the optimal parameters of spray drying to protect the GCWE. Novelty Impact Statement Spray-drying microencapsulation using agave fructans and gum arabic as wall material showed an encapsulation efficiency higher than 90%, which allows preserving the antioxidant compounds present in the green coffee residue extract.

Effect of operational conditions on physicochemical profiles of spray-dried powder of mango (Mangifera indica L.) juice from Tu Quy variety in Vietnam

The spray drying process is widely used to convert fruit juice to powder form, which improves the commercialization and consumption of fruit in powdered form. This research work was conducted to investigate the effects of spraying conditions including wall material concentration, inlet temperature, and feed flow rate on the physicochemical properties of the spray-dried mango powder from the Tu Quy variety in Vietnam. Maltodextrin as a wall material was determined at 10% which revealed an efficiently protective effect on the retention of polyphenol content (308.29±8.62 mg/100 g) and vitamin C content (19.61±0.35 mg/100 g) and exhibited even spherical particles with a smooth surface of the resulted powder. Increasing the inlet temperature was found to remarkably reduce the physicochemical properties of the resulted mango powder. The increase in the feed flow rate to 10 rpm resulted in better retention of polyphenols, and vitamin C content. The drying temperature and flow rate at 150oC and 10 rpm were found to obtain a good structural morphology of spray-dried powder The X-ray diffraction analysis from the resulted powder indicated an amorphous material with a broad hump and no sharp diffraction peaks.

Structuring functional mayonnaise incorporated with Himalayan walnut oil Pickering emulsions by ultrasound assisted emulsification

Nowadays Pickering emulsions have attracted immense attention due to their enhanced stability and numerous food applications. In this context, the present study was aimed to introduce Pickering emulsions stabilized by soy protein isolate (SPI)-maltodextrin (MD)-pectin complex incorporated with Himalayan walnut oil (HWO) for development of novel mayonnaise by ultrasound assisted emulsification. The functional mayonnaise was characterised for its stability, structural, textural, rheological and morphological properties. The rheological and microstructure measurements indicated that use of SPI-pectin HWO emulsions had a viscoelastic solid behaviour (G′ > G″) with highly interconnected gel-like network structure leading to diffused oil droplet distribution. An increase in particle size diameter (1.86–5.09 µm) and hardness values (43.16–69.08 N) was seen with increase in the SPI-pectin wall material concentration. A significant reduction in whiteness (L* value) from 91.12 to 53.52 was noted during storage for encapsulated samples. Mayonnaise formulations containing encapsulated HWO depicted significantly lower peroxide value (2.65 meqO2/kg) after extended storage period in comparison to free oil (8.33 meqO2/kg). FTIR analysis of mayonnaise formulations depicted successful complexation of HWO with SPI-MD-pectin matrix. These findings would be of immense importance in designing of Pickering emulsions stabilized by protein-polysaccharide particles with aim of delivering nutraceuticals associated with myriad health benefits.