Flavor Encapsulation Research Articles

The application of starch‐based ingredients in flavor encapsulation

Flavors are of great importance in consumer satisfaction and affect further consumptions of food products. The preservation of aromatic additives is often a top concern of food manufacturers because aromatics are usually expensive, volatile, delicate and hard to handle. Encapsulation provides an effective approach to protect flavors against evaporation and undesirable reactions during storage by coating them with protective carrier materials. Starch has been considered as an excellent wall material for flavor encapsulation over the years. There has been an increasing demand for starches in flavor encapsulation attributed to their significant benefits, as they are fully biodegradable, widely available, inexpensive, and can be easily modified into derivatives with various properties. This paper intends to give a clear overview of the application of four commonly used starch‐based ingredients, i.e., cyclodextrins, hydrolyzed starches, octenyl succinic anhydride starches and porous starches in flavor encapsulation. This review allows a better understanding of the properties of these starch derivatives, as well as their functions and problems in application of food flavor encapsulation. Future perspectives of starch application in flavor encapsulation are suggested.

Encapsulation of Hydrophilic and Hydrophobic Flavors by Spray Drying

Encapsulation of Hydrophilic and Hydrophobic Flavors by Spray Drying

Applications of nanoliposomes in cheese technology

Among microencapsulation techniques used in food production, nanoliposomes are known to be one of the most interesting methods for the encapsulation of flavours, essential oils, amino acids, vitamins, minerals, enzymes, micro‐organisms, redox agents, colourants, antioxidants and antimicrobials. Research has also been conducted on possible applications of nanoliposomes in cheese production by the encapsulation of ferrous glycinate, ferrous sulphate, antioxidants, nisin, β‐galactosidase and cheese‐ripening enzymes. In this article, nanoliposome application in cheese production has been reviewed under three main themes, namely (i) acceleration of cheese ripening, (ii) fortification of cheese with vitamins and minerals and (iii) increasing shelf life of cheese products. Various aspects of nanoliposome application in cheese technology including currently available preparation methods, efficiency of nanoliposomal enzymes, their effects on the acceleration of cheese ripening as well as rheological and chemical properties of the cheese curd are discussed.

Encapsulation of liquids using a counter rotating twin screw extruder

Until now extrusion is not applied for pharmaceutical encapsulation processes, whereas extrusion is widely used for encapsulation of flavours within food applications. Based on previous mixing studies, a hot melt counter-rotating extrusion process for encapsulation of liquid active pharmaceutical ingredients (APIs) was investigated. The mixing ratio of maltodextrin to sucrose as matrix material was adapted in first extrusion trials. Then the number of die holes was investigated to decrease expansion and agglutination of extrudates to a minimum. At a screw speed of 180min−1 the product temperature was decreased below 142°C, resulting in extrudates of cylindrical shape with a crystalline content of 9–16%. Volatile orange terpenes and the nonvolatile α-tocopherol were chosen as model APIs. Design of experiments were performed to investigate the influences of barrel temperature, powder feed rate, and API content on the API retentions. A maximum of 9.2% α-tocopherol was encapsulated, while the orange terpene encapsulation rate decreased to 6.0% due to evaporation after leaving the die. During 12weeks of storage re-crystallization of sucrose occurred; however, the encapsulated orange terpene amount remained unchanged.

Porous starch for flavor delivery in a tomato-based food application

The aim of this study was to evaluate the performance of porous starch, a newly proposed flavor carrier, in a simulated real industrial application. A liquid tomato flavor was plated onto porous starch, as well as onto maltodextrin, and also spray dried, being the latter the most common flavor encapsulation technique used by the food flavor industry. The three flavor systems were added into a tomato sauce that was subjected to sterilization and ambient storage to verify flavor resistance to sterilization and shelf life, measured by sensory and chemical analyses. The three flavor systems showed a similar flavor content after sterilization and similar behavior during shelf-life. Both sensory and chemical analyses confirmed that the polarity of the solvent used to carry the flavor molecules onto porous starch is a key factor in determining flavor retention over time.

Oxidative stability of high-oleic sunflower oil in a porous starch carrier

This study evaluates the oxidation level of high-oleic sunflower oil (HOSO) plated onto porous starch as an alternative to spray drying. Encapsulated oils were subjected to accelerated oxidation by heat and light exposure, and peroxide value (PV) and conjugated dienes (CD) were measured. Bulk oil was the control. PV increased in all samples with increased light exposure, with similar values being reached by oil carried on porous starch and spray dried oil. The encapsulation processes determined a reduced effect of light on the increase of CD in the oil, as compared to bulk oil. Spray dried oil presented the highest CD in the experimental domain considered. Since similar levels of PV and lower levels of CD were shown in the HOSO carried on porous starch compared to the spray dried HOSO, plating flavour oils on porous starch could be a suitable technological alternative to spray drying, for flavour encapsulation.

Solid state of processed carbohydrate matrices from maltodextrin and sucrose

Various mixtures of maltodextrin, sucrose, and water, as typical compounds of food matrices used for flavour encapsulation via extrusion, were processed in a batch mixing process. Plasticization, melting and caramelization just as the formation of amorphous sucrose were studied. All matrices were plasticized within 2min, resulting in a loss of crystalline sucrose. Melting occurred due to water loss higher than 55%. Caramelization could be correlated to a specific mechanical energy input higher than 300Wh/kg. The glass transition temperature of the caramelized matrices could not be fitted with the Gordon Taylor equation, based on the used compounds. Increasing sucrose content in the preblended powder mixture combined with increasing sample water content increased the crystalline fraction within the matrix. These findings enable a systematically investigation of matrices for encapsulation of flavours within the batch mixing process, which can help to transfer the flavour encapsulation to an extrusion process.

Flavour encapsulation in milk proteins – CMC coacervate-type complexes

Beta-pinene containing microcapsules were prepared by complex coacervation of milk proteins, i.e sodium caseinate (CN) and whey protein isolate (WPI), with carboxymethylcellulose (CMC). Milk proteins – CMC interactions were followed by ζ-potential measurements, while the initial emulsions were characterised for droplet size and biopolymer amount present at the oil/water interface. Response surface methodology was applied to investigate the effects of encapsulation processing variables, including protein/polysaccharide (pr/pl) ratio and volatile compound's mass, on encapsulation yield, loading and efficiency as well as the morphological characteristics of the produced microcapsules. The obtained results revealed that it was possible to encapsulate β-pinene with milk proteins and CMC by complex coacervation, while most of the characteristics evaluated were affected by the process variables. Coacervates prepared at the highest pr/pl ratio of 6.99 and β-pinene mass (6.99 g) were the most effective in encapsulating the flavour compound, something that was more evident in the case of WPI–CMC mixture. Additionally, microcapsule structure, evaluated by Scanning Electron Microscopy analysis, was noticeably affected by the protein/polysaccharide ratio being compact when pr/pl was low and “spongy”-like when it was high.

Encapsulation in a natural, preformed, multi-component and complex capsule: yeast cells

From the first observation about 40 years ago that yeast cells were interesting protective structures that could be used in several industrial applications, processes have been developed enabling technologists to incorporate several compounds possessing different physico-chemical (hydrophobic/hydrophilic) properties. Technologists screened yeast diversity to choose strains possessing the best potential and modified their physiological state to increase the uptake capability and the envelope plasticity, for instance by increasing the amount of lipids. Physico-chemical treatments were also used to improve the uptake and decrease the yeast natural material impact on the final products. For example, yeast cells could be "emptied" of their plasmic material. Yeast cells can also be coated with an additional polymeric material to increase resistance to heat treatment or decrease material liberation.These capsules can be used for several applications including carbonless paper, perfuming tissues and drug targeting, but the main industrial application deals currently with flavour encapsulation, although encapsulation in yeast is also interesting for the global food industry trend for health products.This paper proposes to review the use of yeast as an encapsulation structure focusing particularly on the properties of the yeast capsule and their impact on loading, protection, targeting and release.

An investigation of flavor encapsulation comprising of regenerated cellulose as core and carboxymethyl cellulose as wall

The potential application of flavor encapsulation comprising regenerated porous cellulose particles (RPC) as core and carboxymethyl cellulose (CMC) as wall was investigated using l-menthol as a model flavor. RPC was prepared by sol–gel transition method and characterized by Fourier-transform infrared (FTIR) spectra, scanning electron microscopy (SEM) and micromeritics instruments. The results revealed that the RPC showed the particle size about 300–500 μm as well as the specific surface area about 8.7 m2/g. Based on high adsorptive capability, RPC could encapsulate menthol well and offer high encapsulation yield. The menthol content of RPC-menthol complexes (RPCM) was measured by gas chromatogram (GC) and showed the maximum content of about 12 % menthol with the encapsulation efficiency of 70 %. Besides, RPC provided comparable flavor retention as microcrystalline cellulose during storage under relative humidity of 80 % at 25 °C. CMC was then used to modify RPCM and the construction of RPCM-CMC was confirmed by FTIR and SEM. The studies showed that CMC wall on RPCM surface had no influence on the menthol content and encapsulation efficiency in encapsulation process, but provided a significant increase in menthol retention during storage depending on the content of CMC in RPCM-CMC. Moreover, the stability test at various temperatures showed that both RPCM and RPCM-CMC were stable at room temperature and released flavor at temperatures common in food processing. It was concluded that RPC and CMC modification shows great potential as flavor encapsulant.

Indirect Color Prediction of Amorphous Carbohydrate Melts as a Function of Thermal History

Glassy carbohydrate microcapsules are widely used for the encapsulation of flavors in food applications, and are made using various thermal processes (for example, extrusion). During manufacturing, these carbohydrate melts are held at elevated temperatures and color can form due to nonenzymatic browning reactions. These reactions can negatively or positively affect the color and flavor of microcapsules. The rate of color formation of maltodextrin and maltodextrin/sucrose melts at elevated temperatures was determined spectrophotometrically and was found to follow pseudo zero-order kinetics. The effect of temperature was adequately modeled by an Arrhenius relationship. Reaction rate constants and Arrhenius parameters were determined for individual wavelengths in the visible range (360 to 700nm at 1nm intervals). Transient processes (temperature changes with time) were modeled as a sequence of small isothermal events, and the equivalent thermal history at a reference temperature calculated using the Arrhenius relationship. Therefore, spectral transmittance curves could be predicted with knowledge of the time/temperature relationship. Validation was conducted by subjecting both melts to a transient thermal history. Experimental transmittance spectrum compared favorably against predicted values. These spectra were optionally converted to any desirable color space (for example, CIELAB, XYZ, RGB) or derived parameter (for example, Browning Index). The tool could be used to better control nonenzymatic browning reactions in industrial food processes.

Encapsulation of Natural Flavors in Cyclodextrins: Free Volume Studies by PALS

Positron annihilation lifetime spectroscopy (PALS) is used to study the free-volume in β-cyclodextrin (CD) with the encapsulation of two different essential oils: garlic (Allium sativum) and marjoram (Origanum majorana). The data reveal the presence of a long lifetime component related to the o-Ps. It is observed that the addition of garlic (or marjoram) oil to β-CD results in a decrease of the o-Ps lifetime which was ascribed to a reduction of the free volume holes from 83.6 to 67.7 Å3 (79.1 to 72.6 Å3). Different mechanisms for the encapsulation of garlic and marjoram oils in β-CD are suggested by the PALS parameters.

Properties of encapsulated wasabi flavour and its application in canned food

Summary The encapsulated wasabi flavour prepared from 100% modified starch (HICAP™ 100), HICAP™ 100: maltodextrin (1:1), HICAP™ 100:CAPSUL (1:1) at various flavouring agent concentrations (10, 15 or 20% w/w) was determined for physicochemical properties. All encapsulated treatments were stored at various relative humidity (RH) levels (11%, 33% and 52% RH) and intervally evaluated for encapsulation efficiency (EE) during 60 days of storage. Microcapsules of 20% wasabi flavour derived from the mixture of HICAP™ 100 with maltodextrin and HICAP™ 100 with CAPSUL demonstrated excellent properties including low moisture content, acceptable flowing properties, surface appearance and EE. The release rate of encapsulated flavour increased as the RH increased for most encapsulated treatments. A difference-from-control test was conducted to evaluate the magnitude of wasabi-flavour retention added in the canned tuna spread. The intensity of wasabi-flavour retention in the canned tuna spread with encapsulated flavour agents added was higher than that of the samples without flavour encapsulation.

Encapsulation of food flavors using a natural crosslinking agent

INTRODUCTION Flavors lose their effect beginning from the production step due to their volatile and oxidation labile nature. To prevent this problem, encapsulation of flavors into different materials (e.g. gelatin, gum arabic, whey proteins, pectin, etc) is a well known method. Flavour encapsulation is accomplished by a variety of methods, such as spray drying, extrusion, freeze drying, coacervation and adsorption techniques1. In this study, complex coacervation method was used to encapsulate food flavors into gum arabic/gelatin mixture. Complex coacervation involves more than one colloid and caused by the interaction of two oppositely charged colloids between a poly-anion and a poly-cation, both water-soluble.

Fragrance and Flavor Microencapsulation Technology

Fragrance and flavor are valuable ingredients in toiletries, cosmetics and foods. They play a very important role in these products. However, fragrances and flavors are complex mixtures of comparatively volatile substances and labile components of which the sensory perception can be changed as a result of heating, oxidation, chemical interactions or volatilization. Microencapsulation technology is an effective method to minimize the harm of these problems. Encapsulation of fragrances or flavors has been attempted using various methods. In this paper, the chemical and engineering processes for encapsulation of fragrance and flavor are discussed. The different coating materials and their application are depicted.

Encapsulation of food flavors via coacervation method

INTRODUCTION Flavours play an important role in the consumer preferences for the food products. These highly valuable compounds lose their effect beginning from the production step because of their volatile and oxidation labile nature. Encapsulation of flavours into different materials (e.g. gelatin, gum arabic, whey proteins, pectin, etc) is a well known method to solve this problem. Encapsulation is the technique by which one material or a mixture of materials is coated with or entrapped within another material or system. Flavour encapsulation is accomplished by a variety of methods, such as spray drying, extrusion, freeze drying, coacervation and adsorption techniques 1. Coacervation is defined as the separation into two liquid phases in colloidal systems. The more concentrated phase is known as the coacervate and the other phase is the equilibrium solution 2. This method could efficiently be used in the formation of nanoor microcapsules and a crosslinker is generally used for stabilization.

Oil droplet size determination in complex flavor delivery systems by diffusion NMR spectroscopy

Droplet size distribution of flavor oils in two different solid flavor delivery systems were determined with pulsed field gradient NMR spectroscopy: yeast encapsulation system, a spray dried flavor encapsulation system based on empty yeast cells, and glassy encapsulation system, an extruded solid water soluble carbohydrate delivery system. The oil droplet sizes are limited by the yeast cell walls in the yeast encapsulation system and the size distribution is unimodal according to images from transmission electron microscopy. The droplet size determination with diffusion NMR is based on the Murday and Cotts theory of restricted diffusion of liquids in geometrical confinements. Good fits of the diffusion data could be obtained by applying a unimodal, log-normal size distribution model and average droplet sizes of about 2 μm were found that correspond approximately to the inner diameter of the yeast cells. Scanning electron microscopy images showed a multimodal droplet size distribution in the glassy extruded delivery systems. To fit the NMR data a bimodal log-normal distribution function with five independent fitting parameters was implemented that yielded consistent and robust results. The two size populations were found in the micron and sub-micron range, respectively. The method was sufficiently accurate to depict variation of droplet size distributions in glassy encapsulation systems of different formulation.

Evaluation of a humidity-measuring instrument for the determination of water in spray-dried flavour powders

Spray drying is a common technique for encapsulation of liquid and dry flavours. Control of the water content of spray-dried flavour powders is critical for maintaining product quality and storage stability. Karl Fischer titration is the method of choice for confirming that the product meets specifications, but a simpler technique would be welcome in the quality control laboratory. We report here the results of an evaluation of a humidity-measuring instrument, the Computrac® Vapor Pro®, for determining the water content of spray-dried flavour powders. The instrument heats the sample to drive off moisture, which is measured with a water-specific sensor. The influence of the oven temperature, sample size, purge time, and endpoint detection method were determined for our samples. The optimized Vapor Pro® measurements show excellent correlation (r2 = 0.9923, n = 51) with the reference Karl Fischer method over a range of 1.3% to 7.4% water, with comparable precision. The instrument is thus capable of replacing a Karl Fischer titrator for at-line monitoring and QC evaluation of water in spray-dried flavours.

Encapsulation of Essential Oils of <i>Piper Nigrum</i> and <i>Monodora myristica</i> from South-West Nigeria Using Gum Arabic

Investigations were conducted on the encapsulation of the essential oils of and using gumArabic as an encapsulating agent. The essential oils of these plant materials were extracted using hydro-distillation method. The essential oil yield for was 2.40% while that of was 2.90%. The prepared gum Arabic was used to encapsulate the essential oils of the said plant materials ( and ) at an optimum in-feed concentration and to achieve maximum essential oil (flavour) retention during spray-drying. The gumArabic provided ideal viscosity for the infeed mixtures. The spray-dried samples were analysed for total encapsulated oil, surface oil and moisture content. The moisture content, total oil and surface oil for were 3%, 80% and 5% while for the values were 2.5%, 80% and 4% respectively. Prior to the encapsulation of the essentials, the physico-chemical properties of the oils were evaluated, namely: percentage non-volatile residue, specific gravity, refractive index, acid value, ester value, saponification value and solubility in70% ethanol and the results were: 0.89, 0.8860, 1.4810, 8.20, 82.25, 140.02 and 1:5 clearly soluble respectively for and 1.21, 0.9021, 1.4950, 9.64, 75.32, 118.64 and 1:5 clearly respectively for . The two essential oil samples were well retained in the gum Arabic encapsulation matrices.Keywords: Monodora, African nutmeg, essential oil, Black Pepper, Piper nigrum, flavour encapsulation.

RHEOLOGICAL PROPERTIES OF AQUEOUS DISPERSIONS OF TRAGACANTH AND GUAR GUMS AT DIFFERENT CONCENTRATIONS

ABSTRACT Rheological studies of tragacanth and guar gums dispersions were carried out by means of steady shear (3 to 1000/s) and small amplitude oscillatory shear experiments (0.1 to 10 rad/s) for concentrations up to 8.9 g/L for tragacanth and 7.6 g/L for guar gum at 25C using stress controlled rheometer. The dispersions exhibited shear‐thinning characteristics. A simplified Cross model was adequate to fit the shear‐dependent viscosity behavior for both gums. Model parameters for guar gum were correlated with concentration employing power functions (with flow index constant) and for tragacanth gum the dependence was linear for flow index, power for time constant and exponential for zero‐shear rate viscosity. Mechanical spectra revealed that dispersions behave as dilute systems of coil polymers with trend to entangled systems at the highest concentrations. Loss and storage moduli were correlated with frequency and the resulting parameters were correlated with concentration. Cox–Merz rule holds satisfactorily. PRACTICAL APPLICATIONSGuar and tragacanth gums are natural thickeners that have many applications in pharmaceutical, food, paper, textile, oil painting and cosmetic industries, among others. The addition of these hydrocolloids at low concentration to systems can give a great variety of functions such as enhancement of viscosity, improvement of texture, formation of films, encapsulation of flavors, creation of gel‐structures, etc. In this work, mathematical relationships are proposed for the variation of apparent viscosity and loss and storage moduli with concentration for both gums.