Emulsified spray drying

Lactomul 925 Lactomul AM 240 emulsifier, spray-dried flavors/oils cake dry mixes... 

The second step is to disperse the core material being encapsulated in the solution of shell material. The core material usually is a hydrophobic or water-knmiscible oil, although soHd powders have been encapsulated. A suitable emulsifier is used to aid formation of the dispersion or emulsion. In the case of oil core materials, the oil phase is typically reduced to a drop size of 1—3 p.m. Once a suitable dispersion or emulsion has been prepared, it is sprayed into a heated chamber. The small droplets produced have a high surface area and are rapidly converted by desolvation in the chamber to a fine powder. Residence time in the spray-drying chamber is 30 s or less. Inlet and outlet air temperatures are important process parameters as is relative humidity of the inlet air stream. 

Dried blends of whole egg and yolk with carbohydrates have sucrose or com symp added to the Hquids before spray-drying. Such carbohydrates (qv) preserve the whipping properties of whole egg and yolk by keeping the fat in an emulsified state. Com symp also gives anticaking characteristics, better flowabiHty, and improved dispersibiHty in water. Dried blends of egg and carbohydrate function weU in emulsified, as weU as unemulsified, sponge cakes. 

Since the 1940s, alkanesulfonates have served as emulsifiers in the emulsion polymerization of vinylchloride. Nevertheless, the detailed mechanisms of this process are not yet completely known. An important advantage of using alkanesulfonates is that they produce latices with a high solid content, which can be effectively processed by spray drying [90]. 

The most common method to simultaneously dry and encapsulate flavours is the spray-drying technique (Fig. 21.11). For this technology, carrier materials like maltodextrin, starch and gum arabic are dissolved in water. As a next step, the liquid flavour raw material is emulsified in this slurry. Also non-volatile flavour components can be added. The slurry is atomised and dried in a spraydrying facility. 

The focus of this work was to determine if a glyco-peptide or a simple dextrinized, oxidized starch could be produced which would enhance the behavior of a starch-based polymer for spray dried flavoring production. Enhancement of a starch s lipophilic/hydrophilic balance was anticipated to maintain the polymer s film forming" and cohesive wall development during the spray drying process while improving its emulsifying/interfacial activity capabilities. 

Orange terpenes were emulsified in various carrier s and spray-dried. The spray-dried powders were aged for 3 days at 80 C in a draft oven. Beta-pinene is an oxidation product in orange terpenes which can be measured by GC. The beta-pinene level is proportional to the degree of oxidation of the orange terpenes. High levels of beta-pinene content in the spray-dried powders indicate poor oxidation resistance imparted to the encapsulated terpenes by the carrier. 

Starch octenylsuccinates offer excellent emulsifying properties, flavor oil retention and good oxidation resistance versus gum arabic. They can be made on a variety of starch bases, dextrins or fluidities which provide versatility and improved spray-drying costs. Starch octenylsuccinate are low in cost, domestically produced and are not subject to the market fluctuations that gum arabic encounters. 

The initial step in spray drying of a flavor is the selection of a suitable carrier material. One can divide the major flavor carriers into three classes (and blends thereof) hydrolyzed starches, emulsifying starches, and gums (essentially gum arabic). 

Spray Drying of Orange Oil. Capsul, a modified food starch (National Starch and Chemical Corp., Bridgewater, NJ), was used as the encapsulation agent. Capsul solution with 30 (w/w)solids content in deionized water was prepared. Orange oil (Florida Valencia), 20 (w/w) of solids, was emulsified into... 

Encapsulated Flavors. Modified procedures during the past decade have permitted the preparation of encapsulated flavors with flavor levels over twice that of prior available products. Spray drying has been the principal key to this success. First, an oil flavnr is emulsified into an aqueous solution or is dispersed in an edible carrier material, after which the emulsion is pumped through an atomizer into a high-temperature chamber. The water evaporates rapidly, and particles of carrier material are formed around the flavor. However, some of the flavor component reaches the surface of the product. This requires the addition uf antioxidants to suppress oxidative changes in the flavor ingredient. 

Even more recent has been the introduction of cncapsiilaiion/exirusion. which also permits conversion of Havorants. such as essential oils, into solid form. Spray drying is nut required. In the encapsulation process, the flavor substance is "enrobed." A viscous carbohydrate, with less than ]O f water, is created by heating, after which an emulsifier and acid flavoring ingredients are added. The ingredients are reacted under pressure in a cool alcohol bath, and then the product is extruded to fornt filaments, Thus, the final easy-to-handle product contains the flavor within a small capsule. 

Emulsion. a larger quantity of emulsifier is employed, resulting in a fine particle size emulsion. The polymer after spray drying, is a finely divided powder suitable for use in organosols and plastisols. 

Toppings are spray-dried emulsions made from sodium caseinate, vegetable fat such as palm kernel or coconut fat, and emulsifiers with low polarity, such as acylated (acetylated or lactylated) monoglycerides or propylene glycerol monostearate. 

Sims, R.J., Spray Dried Emulsions in Food Emulsifiers Chemistry, Technology, Functional Properties and Applications, G. Charalambous, G. Doxastakis (Eds.), Elsevier, Amsterdam, 1989, pp. 495-509. 

Whey protein concentrate. The whey protein used was prepared by ultrafiltration and spray drying. Protein content (N x 6.55) was 68% (dry weight). Lipid content was 7.1% (dry weight). In order to study heat induced aggregation by spectrophotometric methods the turbidity of the dilute protein dispersions was too high. The turbidity of whey protein dispersions is caused by lipids associated with proteins probably in the form of emulsified oil droplets. This fraction was removed by precipitation at pH 4.5 from dispersions made in dist. water and separated by centrifugation at 40 000 xg. 

Probiotics may be encapsulated in protein-based emulsions. Picot and Lacroix (2003) prepared microcapsules by emulsifying milkfat containing micronized skim milk powder (as a surrogate for freeze-dried bacteria) with heat denatured whey proteins and then spray drying. Incorporation rates of up to 58% milk fat and 29% skim milk... 

Klinkesom, U., Sophanodora, P., Chinaclioti, P., Decker, E.A., and McClements, D.J. (2006). Characterization of spray-dried tuna oil emulsified in two-layered interfacial membranes prepared using electrostatic layer-by-layer deposition. Food Res. Int. 39,449-457. 

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