Volatile encapsulation stabilization

Spray drying is the most widely used, least expensive and favored route among the methods available for encapsulation (2) Various theories of volatile retention in spray drying have been proposed and reviewed (3). In addition to the nature of flavor compounds, flavor retention is governed by type of carriers, infeed composition, solids concentration (4), dryer inlet/exit air temperature, air velocity and humidity, feeding rate and atomization characteristics. In addition to flavor retention,the stability of the encapsulated product, as mentioned earlier, is also of importance and is governed by nearly the same parameters. However,the effect and mechanics of each individual factor are much less understood. 

To deal with the hazardous status of ashes from CCA-treated wood, the arsenic must either be extracted or the ashes would need to be encapsulated through solidification/stabilization. Hypothetically, the recovery and reuse of arsenic from the incineration of CCA-treated wood could reduce arsenic mining and imports. However, arsenic use has declined in recent years (Chapter 5) and there is little economic incentive to incinerate solid wastes and recover any volatile arsenic (Leist, Casey and Caridi, 2000, 126, 127). 

A pressure DSC test (semi-closed sample pan, encapsulated in air, under 500 psig of N2) and a non-pressure DSC test (semi-closed sample pan, encapsulated in air, at ambient pressure) are used in our initial screen for several reasons. The pressure DSC allows the thermal stability of liquids to be examined near, at, or above their boiling points. It also suppresses the evaporation of volatile materials from the sample, which can hide an exotherm. This can be especially important when testing evaporation residues. A comparison of the results of both tests gives an indication of the effect of pressure on the decomposition of the material. It will also give an indication if oxidation is an... 

The sample s weight loss versus temperature from a TGA measurement reveals crucial information regarding the thermal stability, decomposition volatiles and kinetic properties of the material which are a critical concern in the material s use as an encapsulant. 

In this paper, the thermal stability of the silicone elastomers, base silicone resins, fillers, and their interactions with each other within the silicone matrix are described. Thermal decomposition volatiles, obtained indirectly through solvent extractables, reaction kinetics of the materials as integrated circuit (IC) devices encapsulants will be discussed. 

Cyclodextrins (CDs) are commonly used to improve the stability of flavor via the encapsulation of certain specific ingredients that naturally exist in food materials. The method is often called molecular encapsulation because the flavor ingredients are encapsulated in the molecular cavity of CDs. CDs form inclusion complexes with a variety of molecules including flavors, fats, and colors. Most natnral and artificial flavors are volatile oils or liquids, and the complexation with CDs provides a promising alternative to the conventional encapsulation technologies for flavor protection. 

Several works have been published involving CDs and EOs/volatiles. The association of those compounds (either as inclusion complexes or not) often advantageously modifies various physicochemical properties of the encapsulated molecules such as aqueous solubility and stability. Cabral-Marques (2010) has recently reviewed some issues on flavors/fragrances and/or EO and volatiles using CDs encapsulation approach. 

Volatilization and thermal destmction are the primary methods of remediation of lighter hydrocarbons in the hot-mix asphalt process. Solidification/stabilization is the secondary method of remediation. Heavier hydrocarbons remaining in the soil after the drying step are encapsulated within the asphalt/aggregate matrix. 

---