Emulsifying starches, carrier material

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 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). 

The materials to be spray dried, e.g. flavouring concentrates or fmit, have to be prepared into a solution or an emulsion. Flavour concentrates, e.g. essential oils, extracts and/or mixtures of these with other flavouring substances, are emulsified in water with gum arabic and then homogenised with a solution of the dry carrier. Useful carriers are modified starch products, maltodextrin, sugar, modified whey proteins. 

The emulsifiers and emnlsifying techniques to produce nanoparticle encapsulated powders (Jafari et al., 2007a). In the case of fish oil encapsulated in maltodextrin combined with modified starch or whey protein concentrate, spray-dried powders were obtained from nanoemulsions (210-280 nm) prepared by microfluidization, with a good efficiency (Jafari, 2009). And the satnration of the carrier solution of wall materials influenced the flavor retention and surface oil content (Penbundiktul et al., 2012). 

In the food industry, because the spray dryer is commonly available, economical, fast, and produces good-quality material [16], it becomes the most common means of encapsulation. The encapsulation process is simple and similar to the one-stage spray drying process. The coated material is called the active or core material, and the coating material is called the shell, wall material, carrier, or encapsulant [43]. The active material to be encapsulated, such as an oil or fia-vor in an oil base, is dispersed in a hydrocolloid carrier, e.g., gelatin, modified starch, dextrin or maltodextrin, or gum arabic. After the emulsifier is added, the mixture must be... 

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