Flavor retention, spray-dried food products

Retention of Flavor in Spray-Dried Food Products 253... 

Possibly the most important, and least understood, aspect of spray-dried flavorings manufacture is the role the wall material plays in this process. The polymers utilized for this product are controlled by FDA constraints, cost, finished product labelling considerations and compatability, functionality and historical usage. Given these considerations, polymers selected for the retention and maintenance of labile flavors and aromas in industrial spray dried, food grade systems include both carbohydrate (hydrolyzed starches, "lipophilic starches, plant exudates) and protein. The importance of these wall materials should not be underestimated. 

Another area of interest to optimize the encapsulation efficiency of food flavors and oils by SD is the submicronization of the droplets oil of the emulsion. It has been well documented that emulsion droplet size has a pronounced effect on the encapsulation efficiency of different core materials by SD (Jafari et al., 2008). The findings clearly show that reducing emulsion size can result in encapsulated powders with higher retention of volatiles and lower content of unencapsulated oil at the surface of powder particles. The presence of oil on the surface of the powder particles is the most undesirable property of encapsulated powders, and it has been pointed out as a frequent problem with the quality of spray-dried products. This surface oil not only deteriorates the wettability and dispersability of the powder, but it is also readily susceptible to oxidation and to the development of rancidity. 

Example 1.3-7 Flavor retention When food products are spray-dried, they lose a lot of flavor. However, they lose less than would be expected on the basis of the relative vapor pressures of water and the flavor compounds. The reason apparently is that the drying food often forms a tight gellike skin across which diffusion of the flavor compounds is inhibited. What diffusion model should you use to study this effect ... 

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