Physicochemical and Thermal Stability of Microcapsules of Cinnamon Essential Oil by Spray Drying

Effect of Encapsulation Techniques on Aroma Retention of Pistacia terebinthus L. Fruit Oil: Spray Drying, Spray Freeze Drying, and Freeze Drying

The primary aim of this investigation was to assess the impact of varying the ratio of gum arabic to maltodextrin and employing diverse encapsulation techniques on the properties of the powdered substance and the capacity to retain the aromatic attributes of terebinth fruit oil. Distinct ratios of gum arabic to maltodextrin (75:25, 50:50, and 25:75) were employed to fabricate oil-in-water emulsions. The utmost stability of the emulsion was realized at a gum arabic to maltodextrin ratio of 75:25, characterized by a minimal creaming index and an even and small-scale dispersion. The encapsulation techniques employed included spray drying (SD), spray freeze-drying (SFD), and freeze-drying (FD). These methodologies were compared based on encapsulation efficiency, desiccation yield, powder attributes, and the capacity to retain aroma. The encapsulation efficiencies were notably higher (>90%) in SD, particularly with the application of an ultrasonic nozzle and a two-fluidized nozzle (2FN), in contrast to those obtained through SFD and FD. Notably, SD employing an ultrasonic nozzle exhibited superior preservation of volatiles (73.19%) compared to FD (24.45%), SD-2FN (62.34%), and SFD (14.23%). Among the various components, α-pinene and linalool stood out with near-perfect retention rates, close to 100%.

Encapsulation and delivery systems of cinnamon essential oil for food preservation applications

Food safety threats and deterioration due to the invasion of microorganisms has led to economic losses and food-borne diseases in the food industry; so, development of natural food preservatives is urgently needed when considering the safety of chemically synthesized preservatives. Because of its outstanding antioxidant and antibacterial properties, cinnamon essential oil (CEO) is considered a promising natural preservative. However, CEO's low solubility and easy degradability limits its application in food products. Therefore, some encapsulation and delivery systems have been developed to improve CEO efficiency in food preservation applications. This work discusses the chemical and techno-functional properties of CEO, including its key components and antioxidant/antibacterial properties, and summarizes recent developments on encapsulation and delivery systems for CEO in food preservation applications. Since CEO is currently added to most biopolymeric films/coatings (BFCs) for food preservation, most studies have shown that encapsulation systems can improve the food preservation performance of BFCs containing CEOs. It has been confirmed that various delivery systems could improve the stability and controlled-release properties of CEO, thereby enhancing its ability to extend the shelf life of foods. These encapsulation techniques include spray drying, emulsion systems, complex coacervation (nanoprecipitation), ionic gelation, liposomes, inclusion complexation (cyclodextrins, silica), and electrospinning.

Effect of PCL nanofiber mats coated with chitosan microcapsules containing cinnamon essential oil for wound healing

INTRODUCTION

Cinnamon is one of the most common spices that has been studied for its anti-inflammatory, antioxidant, and antibacterial properties in wound healing. The purpose of this study was to evaluate the effectiveness of polycaprolactone nanofiber mats coated with chitosan microcapsules loaded with cinnamon essential oil in wound healing.

MATERIAL AND METHODS

For this purpose, chitosan microcapsules containing cinnamon essential oil (µCS-CiZ) were prepared by ion gelation and PCL nanofibers by electrospinning. The size of the µCS-CiZ and the morphology of nanofibers were evaluated by DLS and FESEM methods. In order to evaluate wound healing, 48 rats in 4 groups of Control, µCS-CiZ, PCL, and PCL + µCS-CiZ and were examined on days 7, 14, and 21 in terms of macroscopy (wound closure rate) and histology (edema, inflammation, vascularity, fibrotic tissue, and re-epithelialization).

RESULTS

The particle size of the µCS-CiZ and the diameter of the nanofibers were estimated at about 6.33 ± 1.27 μm and 228 ± 33 nm, respectively. On day 21, both µCS-CiZ and PCL groups showed a significant decrease in wound size compared to the control group (P < 0.001). The PCL + µCS-CiZ group also showed a significant decrease compared to the µCS-CiZ (P < 0.05) and PCL groups (P < 0.05). Histological results showed further reduction of edema, inflammation, and vascularity in granulation tissue and appearance of moderate to marked fibrotic tissue in PCL + µCS-CiZ group compared with the other groups.

CONCLUSION

The results of the study showed that the combined use of PCL + µCS-CiZ indicates a synergistic effect on improving wound healing.

Nutmeg Essential Oil, Red Clover, and Liquorice Extracts Microencapsulation Method Selection for the Release of Active Compounds from Gel Tablets of Different Bases

The current study presents the most suitable method for encapsulating nutmeg essential oil with liquorice and red clover. Two widely used methods, spray-drying and freeze-drying, were employed to find the most suitable for essential oil volatile compounds’ protection. Results showed that freeze-dried capsules (LM) had a higher yield (85.34%) compared to the exact formulation of spray-dried microcapsules (SDM)—45.12%. All the antioxidant and total phenolic compounds’ results obtained with the LM sample were significantly higher compared with SDM. LM microcapsules were incorporated in two different bases with no additional sugar (gelatin and pectin) for targeted release. Pectin tablets had firmer and harder texture properties, while gelatin tablets had a more elastic texture. There was a significant impact on texture changes caused by microcapsules. Microencapsulated essential oil with extracts can be used alone or in a gel base (pectin or gelatin, depending on user preferences). It could be an effective product to protect the active volatile compounds and regulate the release of active compounds and give a pleasant taste.

Microencapsulation as a Route for Obtaining Encapsulated Flavors and Fragrances

Microencapsulation methods for active substances, such as fragrance compounds and aromas, have long been of interest to researchers. Fragrance compositions and aromas are added to cosmetics, household, and food products. This is often because the choice of a particular product is dictated by its fragrance. Fragrance compositions and aromas are, therefore, a very important part of the composition of these items. During production, when a fragrance composition or aroma is introduced into a system, unfavorable conditions often exist. High temperatures and strong mixing have a detrimental effect on some fragrance compounds. The environments of selected products, such as high- or low-pH surfactants, all affect the fragrance, often destructively. The simple storage of fragrances where they are exposed to light, oxygen, or heat also has an adverse effect. The solution to most of these problems may be the encapsulation process, namely surrounding small fragrance droplets with an inert coating that protects them from the external environment, whether during storage, transport or application, until they are in the right conditions to release the fragrance. The aim of this article was to present the possible, available and most commonly used methods for obtaining encapsulated fragrances and aromas, which can then be used in various industries. In addition, the advantages and disadvantages of each method were pointed out, so that the selection of the appropriate technology for the production of encapsulated fragrances and aromas will be simpler.

Physicochemical properties of kashk supplemented with encapsulated lemongrass extract

Kashk is a perishable fermented dairy product. Since chemical preservatives are harmful for human health, we aimed to study lemongrass (Cymbopogon citratus L.) as a natural preservative. First, we assessed the phytochemical properties of lemongrass extract. Then, we added lemongrass extract and microencapsulated lemongrass extract to kashk samples. Finally, we analyzed their physicochemical and sensorial properties during 60 days of storage. Catechin (419.04 ± 0.07 mg/L), gallic acid (319.67 ± 0.03 mg/L), and chloregenic acid (4.190 ± 0.002 mg/L) were found to be the predominant phenolic constituents in lemongrass. Total phenolics, total flavonoids, and antioxidant activity (IC50) values of the lemongrass extract were 26.73 mg GA/g, 8.06 mg Quercetin/g, and 2751.331 mg/L, respectively. The beads were spherical in shape with a 35.03-nm average particle diameter and 47.81% microencapsulation efficiency. The pH of the supplemented kashks decreased during the storage time. They showed lower acid degree values than the control at the end of storage. The peroxide, p-anisidine, and thiobarbituric acid values of the sample fortified with microencapsulated lemongrass extract were 6.15, 4.76, and 44.12%, respectively, being the lowest among the samples. This kashk sample had the highest hardness (570.62 ± 21.87 g), adhesiveness (18.10 ± 4.36 mJ), and cohesiveness (0.56 ± 0.25) but the lowest chewiness (72.66 ± 3.08 mJ) among the samples. It also had a better sensory profile than the control samples. Our results indicated that microencapsulated lemongrass extract could be incorporated into kashk to ensure suitable sensorial and textural properties. Furthermore, it may delay fat oxidation and lipolysis during storage.

Spray drying encapsulation of essential oils; process efficiency, formulation strategies, and applications

Essential oils (EOs) have many beneficial qualities, including antimicrobial, antioxidant, antiviral, and antifungal activities, along with good aroma, which have played a significant role in pharmaceutical, textile, and food industries. However, their high volatility and sensibility to external factors, as well as susceptibility to deterioration caused by environmental and storage conditions, or even common processing, and consequently limited water solubility, makes it difficult to incorporate them into aqueous food matrices and limits their industrial application. Spray-drying encapsulation has been proposed as a solution and a challenging research field to retard oil oxidation, extend EO's shelf life, improve their physicochemical stability, achieve controlled release, suggest novel uses, and therefore boost their added value. The objective of this review is to discuss various used wall materials, infeed emulsion properties, the main formulation and process variables affecting the physicochemical properties and release characteristics of the EOs-loaded particles obtained by spray-drying, the stability of EOs during storage, and the applications of encapsulated EOs powders in foods and nutrition, pharmaceuticals, and textile industries. The current review also summarizes recent advances in spray drying approaches for improving encapsulation efficiency, flavor retention, controlled release, and applicability of encapsulated EOs, thereby expanding their use and functionalities.

Development of a spray-dried conjugated whey protein hydrolysate powder with entrapped probiotics

Bifidobacterium animalis ssp. lactis ATCC27536 and Lactobacillus acidophilus ATCC4356 were encapsulated in a conjugated whey protein hydrolysate (WPH10) through spray drying. Probiotic cultures were added at the ratio of 1:1 into the conjugated WPH10 solution at a spiking level of about 10 log₁₀ cfu/mL. The mixture was spray dried in a Niro drier with inlet and outlet temperatures of 200°C and 90°C, respectively. The final dried product was determined for cell viability and further stored for 16 wk at 25°, 4°, and -18°C to monitor viability and functionality. Micro images showed the presence of link bridges in non-conjugated WPH10, whereas, in the case of conjugated WPH10, round particles with pores were observed. The mean probiotic counts before and after spray drying were 10.59 log₁₀ cfu/mL and 8.98 log₁₀ cfu/g, respectively, indicating good retention of viability after spray drying. The solubility and wetting time of the WPH10-maltodextrin (MD) encapsulated probiotic powder were 91.03% and 47 min, whereas for WPH10, the solubility and wetting time were 82.03% and 53 min, respectively. At the end of storage period, the counts were 7.18 log₁₀ cfu/g at 4°C and 7.87 log₁₀ cfu/g at -18°C, whereas at 25°C the counts were significantly reduced, to 3.97 log₁₀ cfu/g. The solubility of WPH-MD powder was 82.36%, 83.1%, and 81.19% at -18°C, 4°C, and 25°C, respectively, and wetting times were 61 min, 60 min, and 63 min at -18°C, 4°C, and 25°C, respectively. By contrast, for WPH10 powder, the solubility significantly reduced to 69.41%, 69.97%, and 68.99% at -18°C, 4°C, and 25°C, and wetting times increased to 71 min, 70 min, and 72 min at -18°C, 4°C, and 25°C, respectively. The conjugated WPH10 is thus demonstrated as a promising carrier for probiotics and can be further used as an ingredient for developing functional foods, to harness their enhanced functionality and health benefits derived from both WPH and probiotics.

Microencapsulation of Essential Oils by Spray-Drying and Influencing Factors

Essential oils (EOs) are known as any aromatic oily organic substances which are naturally synthesized in plants. Exhibiting a broad range of biological activities, EOs have played a key role in numerous industries for ages, including pharmaceutical, textile, and food. However, the volatility and high sensitivity to environmental influences pose challenges to the application of EOs on industrial scale. Microencapsulation via the spray-drying method is one of the promising techniques to overcome these challenges, thanks to the presence of wall materials that properly protect the core EOs from oxidation and evaporation. By optimization of key factors related to the infeed emulsion properties and spray-drying process, the encapsulation efficiency and retention of encapsulated EOs could be significantly improved, thus allowing a wide range of EO applications. This review attempts to discuss on different determining factors of the spray-drying process to develop an effective encapsulation formula for EOs. Furthermore, recent applications of encapsulated EOs in the fields of foods, pharmaceuticals, and textile industries are also thoroughly addressed.

Fish Oil Microcapsules as Omega-3 Enrichment Strategy: Changes in Volatile Compounds of Meat Products during Storage and Cooking

This work aims to analyze the effects of processing and storage on the volatile compound profile of different meat products enriched in ω-3 polyunsaturated fatty acids (PUFA). Monolayered (Mo) and multilayered (Mu) microcapsules of fish oil were tested. The profiles of volatile compounds were analyzed by solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS). The enrichment with Mo significantly increases the abundance of volatile compounds from lipid oxidation and markers of ω-3 PUFA oxidation, which may be related to the multilayer structure of chitosan–maltodextrin in Mu that achieves greater fish oil protection than the simple coating of maltodextrin in Mo. Besides, the changes in volatile compounds during storage depends on the type of fish oil microcapsules and the meat products, having an increased abundance of ω-3 PUFA oxidation markers in dry-cured sausages added with Mo. However, the enrichment of these meat products with Mo and Mu does not modify the usual variations in the volatile compound profile during culinary cooking. Thus, the addition of multilayer fish oil microcapsules may be a suitable option for enrichment of meat products in ω-3 PUFA without modifying the abundance of volatile compounds, including oxidation markers.

Preparation and Characterization of Double-Layered Microcapsules Containing Nano-SiO2

The double-layered microencapsulation technology has been used in many fields. In this study, the double-layered microencapsulated anthocyanin of Passiflora edulis shells (APESs) was prepared via complex coacervation using gelatin and gum Arabic as the first wall materials (single-layered microcapsules (SMs)) and using gum Arabic containing nano-SiO2 as the second wall material (double-layered microcapsules (DMs)/nano-SiO2) to enhance the stability of the core material. Properties of microcapsules were analyzed on the basis of EE, morphology, scanning electron microscopy (SEM), droplet size, moisture content, and differential scanning calorimetry (DSC). The results showed that the EE values of SMs, DMs, and DMs/nano-SiO2 were 96.12%, 97.24%, and 97.85%, respectively. DMs/nano-SiO2 had the lowest moisture content (2.17%). The average droplet size of DMs/nano-SiO2 (34.93 μm) was higher than those of SMs and DMs. DSC indicated that the melting temperature of DMs/nano-SiO2 was 73.61°C and 45.33°C higher than those of SMs and DMs, respectively. SEM demonstrated that DMs/nano-SiO2 had the smoothest surface compared with the other two kinds of microcapsules. The storage stability of APESs and their microcapsules indicated that the stability of the microcapsules was improved by adding DMs/nano-SiO2 into the wall material of microcapsules. These results indicated double-layered microcapsules containing silica nanoparticles contribute to the stability of the core material.

Effect of Omega-3 Microcapsules Addition on the Profile of Volatile Compounds in Enriched Dry-Cured and Cooked Sausages

The main goal of the present study was evaluating the effect of enriching meat products (cooked (C-SAU) and dry-cured sausages (D-SAU)) with monolayered (Mo) and multilayered (Mu) fish oil microcapsules on the profile of volatile compounds, with special interest in lipid oxidation markers. For that, Solid-Phase Microextraction (SPME) and Gas Chromatography-Mass Spectrometry (GC-MS) were used. Significant differences were found in the volatile compound profile between Mo and Mu, which was been reflected in the meat samples. Thus, in general, volatile compounds from lipid oxidation have shown higher abundance in Mo and C-SAU and D-SAU enriched with this type of microcapsule, indicating that the wall of Mu (chitosan-maltodextrine) might protect the encapsulated bioactive compounds more effectively than that of Mo (maltodextrine). However, this finding is not reflected in the results of previous studies evaluating the sensory perception and oxidation stability of C-SAU and D-SAU, but it should be considered since unhealthy oxidation products can be formed in the enriched meat products with Mo. Thus, the addition of Mu as an omega-3 vehicle for enriching meat products may be indicated.

Evaluación de la biomasa residual (cereza) de café como sustrato para el cultivo del hongo comestible Pleurotus ostreatus

En la actualidad,el desarrollo de nuevos productos alimenticios que posean la incorporación de principios activos se ha convertido en un factor de vital importancia para que las industrias alimenticias puedan competir en el mercado, brindando solución a las necesidades actuales y futuras de sus clientes. La microencapsulación se presenta como una novedosa alternativa para generar productos con valor agregado, ya que permite evitar la degradación de compuestos activos, así como también desagradables cambios en el sabor, especialmente en el caso de los aceites esenciales. Se estudió la microencapsulación de aceite de oliva y aceite de almendra desde la formulación de una emulsión para generar las microcápsulas que posteriormente se obtuvieron por el método de secado por atomización en el Minispray Dryer B-290. Se analizaron la morfología, el porcentaje de aceite encapsulado y las tasas de liberación dentro del cuerpo humano. Los resultados obtenidos permitieron determinar que es posible encapsular aceites esenciales por el método de secado por atomización. Esto permite prevenir la degradación de los ácidos grasos en el almacenamiento de aceites y la digestión gástrica, además de entregarlos directamente en el intestino delgado. Por otro lado, un aceite con mayor porcentaje de ácidos grasos incrementa la tendencia de aglomeración de las microcápsulas. Finalmente, se comprobó que las microcápsulas con maltodextrina como material de pared pueden retener mayor cantidad de aceite de almendra, en comparación con el aceite de oliva

A Novel Shell Material-Highland Barley Starch for Microencapsulation of Cinnamon Essential Oil with Different Preparation Methods

Highland barley starch (HBS), as a carbohydrate shell material with excellent performance in microcapsule applications, has rarely been reported. In the present study, three different microcapsules (CEO-SWSM, CEO-PM, and CEO-UM) were synthesized successfully via saturated aqueous solution method, molecular inclusion method and ultrasonic method, respectively, using HBS as shell material coupled with cinnamon essential oil (CEO) as the core material. The potential of HBS as a new shell material and the influence of synthetic methods on the performance of microcapsules, encapsulation efficiency (EE), yield, and release rate of CEO-SWSM, CEO-PM, and CEO-UM were determined, respectively. The results confirmed that CEO-PM had the most excellent EE (88.2%), yield (79.1%), as well as lowest release rate (11.5%, after 25 days of storage). Moreover, different kinetic models were applied to fit the release process of these three kinds of microcapsules: CEO-SWSM, CEO-PM, and CEO-UM had the uppermost R-squared value in the Higuchi model, the zero-order model, and the first-level model, respectively. Over all, this work put forward a novel perspective for the improved encapsulation effect of perishable core materials (e.g., essential oil) for the food industry.

Microencapsulation of cocoa liquor nanoemulsion with whey protein using spray drying to protection of volatile compounds and antioxidant capacity

The aim of this study was microencapsulated a nanoemulsion of cocoa liquor with whey protein by spray drying, and evaluate the effect of different inlet drying temperatures on the properties of microcapsules. The nanoemulsion showed a particle size of 202.13 nm, PdI of 0.424, and ζ-potential of -25.20 mV. The inlet drying temperature showed differences in physicochemical properties of microcapsules. Microcapsules presented good thermal stability and protection against the melting of cocoa liquor. Microcapsules obtained showed excellent yields of polyphenolic compounds (78-93%), and high retention of volatile compounds, especially of pyrazines. Greater microencapsulation yield of bioactive compounds and retention of volatile compounds was obtained at higher drying temperature (180 °C). Excellent stability of polyphenols content, antioxidant capacity, and volatile compounds of cocoa liquor were observed during storage of the microcapsules at different temperature conditions, indicating the feasibility of this powder for its incorporation into functional foods.

Encapsulation of Piper aduncum and Piper hispidinervum essential oils in gelatin nanoparticles: a possible sustainable control tool of Aedes aegypti, Tetranychus urticae and Cerataphis lataniae

BACKGROUND

The encapsulated essential oils (EOs) of Piper aduncum L. and Piper hispidinervum C. DC. in gelatin nanoparticles were evaluated against Aedes aegypti Linn., Tetranychus urticae Koch and Cerataphis lataniae Boisd.

RESULTS

Encapsulation efficiency of the EOs was measured for absolute concentrations of 500 µg mL^-1 (79.2 and 72.7%) and 1000 µg mL^-1 (84.5 and 82.2%). The loaded nanoparticles were nearly spherical and well dispersed. The nanoparticles loaded with P. hispidinervum EO had an average size of 100 ± 2 nm, while the nanoparticles containing P. aduncum EO ranged from 175 ± 4 to 220 ± 4 nm. According to zeta potential analysis, the nanoparticles loaded with P. hispidinervum and P. aduncum EOs presented values around -43.5 ± 3 and -37.5 ± 2 mV respectively. The controlled release of EOs was described by the anomalous mechanism of Korsmeyer-Peppas. Both encapsulated EOs reached lethal dosages within 24 h of exposure and total mortality of the tested pests.

CONCLUSION

The present work successfully developed gelatin-based nanoparticles that served as carriers for the EOs of P. aduncum and P. hispidinervum to be applied as a sustainable control tool of A. aegypti, T. urticae and C. lataniae. The developed loaded nanoparticles presented high encapsulation efficiency and EO concentration release higher than lethal dosages. This indicates that it is feasible to use gelatin-based nanoparticles loaded with P. aduncum and P. hispidinervum EOs to control the tested pests. © 2018 Society of Chemical Industry.