Encapsulated flavor

Earl Grey tea is flavored with the peel oil of bergamot, a citrus fruit, which is added by spraying onto black tea before final packaging. Other flavors may also be applied to black tea by spraying onto the leaves, incorporation of flowers into the blend, or by addition of encapsulated flavor crystals. Other common flavored teas include Rose Congou and Lychee. 

Flavor Release. Encapsulated flavors find uses throughout the food industry. One major example would be beverage dry mixes. Maltodextrins and corn syrup solids have excellent cold water solubility, so their use in encapsulated flavors will provide a rapid release of flavors used in beverage applications. Maltodextrins and low DE corn syrup solids also have very little flavor or sweetness of their own, form clear solutions, and virtually disappear once in an application. 

As can be seen from the data in TABLE 5 the low viscosity starch octenyl-succinate closely matches the oxidation resistance of gum arabic. This product would offer improved shelf-life over a standard starch dextrin and similar stability to a gum arabic encapsulated flavor. 

Recently,it was reported that when maltodextrins were used as the encapsulating agent, increasing the dextrose equivalent by 10 could result in a three to six fold enhancement in shelf life (5). The reduction in emulsion size of feed emulsion also improved the shelf stability (Risch, S. J., University of Minnesota, personal communication, 1986). However, the influence of particle size distribution on the stability of encapsulated flavors has not been clearly addressed in the literature. 

In summarizing the work of Miller and Mutka ( ), they have found that optimizing the cook temperature, emulsifier level and extrusion vessel pressurization permits the production of encapsulated flavoring of high flavor load. While the patent claims loadings up to 35%, the practical limit appears to be 16-20%. While this is comparable to the flavor loading typically... 

The encapsulation of food flavors presents a very unique and challenging area of investigation. Commercial production of encapsulated flavors is accomplished by a variety of methods. 

This symposium was developed to provide an overview of existing processes and to investigate new developments. The speakers came from industry and academia to provide two perspectives applied research with immediate product benefits and basic research, which can contribute information for long-term improvements. Whereas many people are involved in the manufacture and use of encapsulated flavors, there is little published information on how encapsulation is accomplished and what factors affect encapsulation processes. This book represents the compilation of the information presented at the symposium. We hope it will serve as a reference for the people who work in all aspects of the food and flavor industry who are interested in the encapsulation of flavors. We are sincerely grateful to all of the authors who were willing to present information at the symposium and who cooperated by preparing manuscripts. We appreciate all of your efforts. 

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. 

Jutka. JR. and D.B Nelson "Prcparalion of Encapsulated Flavors with High Flavor Level Frmd Technology. 154 (April 1988],... 

Uhlemann J., Schleifenbaum B., Encapsulated Flavors for Intelligent Products, H R Contact, 79,... 

However, if protease activity were involved, such preparations of methloninase from putIda could provide self-destructing enzyme systems for encapsulated, flavor-producing systems (65) that would prevent over-production of methanethiol and hydrogen sulfide. Alternatively, it might be possible to use other sources of methloninase, such as Brevlbacterlum linens (7 35) or Aspergillus oryzae (56, 57), as systems with potentially less protease activity. In any event further studies will be required to determine if alpha-ketobutyrlc acid assays provide suitable data for indexing methloninase activity In flavor systems. 

Release and Oxidation of Encapsulated Flavors during Storage.12... 

RELEASE AND OXIDATION OF ENCAPSULATED FLAVORS DURING STORAGE... 

Implication of Glass Temperature on Storage Stability of Encapsulated Flavors... 

In general, the rotational and vibrational motions are limited in the amorphous glassy state. In the rubbery state, on the other hand, large-scale molecular motion, such as translational motion, is possible (Ubbink and Schoonman, 2003). Therefore, the encapsulated flavors or oils exist stably in the amorphous glassy state, but in the rubbery state some deterioration may take place. Since an amorphous state is not an equilibrium state, a thermodynamic driving force tends to shift the amorphous state to a more stable crystal state, resulting in a time-dependent crystallization, solidification of powders, and caking. 

Figure 1.12 is a schematic illustration of a spray-dried particle in a humid air environment in which the particle would adsorb water vapor this is then followed by state changes of carrier matrices from the amorphous state to a rubbery state. The encapsulated flavors can easily move in the matrix of the carrier matrices. At the same time, the oxygen uptake into the wall matrix becomes higher and the oxidation of the encapsulated flavors progresses. The most interesting point is that around the glass transition temperature, both release and oxidation rate constants change nearly in the same trends with T- T, as shown in Figure 1.11. This implies that the flavor diffusion and the oxygen upt e can be treated as a similar behavior.

In order to observe encapsulated flavor droplets (emulsion) inside a spray-dried particle, ethyl-n-butyrate was used as a model flavor. Nile red was dissolved in ethyl-n-butyrate and used as a fluorescein probe of the oil phase (ethyl-n-butyrate emulsion) of the solution. The labeled flavor was added to the carrier solution and was emulsified. 

Whorton C, Reineccius GA. 1995. Evaluation of the mechanisms associated with the release of encapsulated flavor materials from maltodextrin matrices. In Risch SJ, Reineccius GA (Eds.), Encapsulation and Controlled Release of Food Ingredients, pp. 143-160. Washington, DC ACS. 

The number of methods for chemical encapsulatiod is actually far less. They are necessary because they are very effective in encapsulating liquids and small core sizes. In particular, it is possible to encapsulate flavors and fragrances down to lOjum in size. 

When selecting SD to produce an encapsulated food ingredient, one is generally looking for high production in a short time and for a product in a powder form. Spray-dried microparticles are commonly used to encapsulate flavors or lipids, and the release mechanism is generally linked to... 

---