What is Spray Drying?
Spray drying for microencapsulation is very different than fluidized bed processes. In spray drying for encapsulation, we change a liquid into a powdered form.
Unlike the fluidized bed methods, spray drying does not produce a full microencapsulation. We are not building a shell or matrix on the outside of the particle. Instead, the spray drying process creates a dispersion or emulsion of an ingredient within another ingredient, and then dries this emulsion very quickly. On the outside surfaces of the resulting dry particles, there will always be some of the active component or active ingredient, while the inside core is much more protected.
Key points of difference in the process of spray drying for encapsulation:
-
The Spray drying process effectively turns liquids into powders.
-
Spray drying starts with an emulsion or dispersion.
-
Spray dried materials are not fully encapsulated.
Spray Drying for Fortification
There is often a need to provide nutrients that otherwise would or could not be consumed readily, and that’s when fortification comes into play. If you are lacking Vitamin D3 and cannot be out in the sunlight for significant time, then the best way to get it is through a supplement or a fortified product. To get a fat-soluble such as Vitamin D3 into a product, spray drying is a technique that could be used. Spray drying, simply stated, allows D3 crystals to be dissolved/suspended into an oil phase, then mixed with a carrier such as maltodextrin or gum arabic, and then spray dried to remove the water under heat, thus resulting in a spray dried D3 powder. By converting the crystals into usable powder form, this powder can now easily be added into products that need to be fortified, enabling your product to achieve your targeted Recommended Daily Value.
Spray Drying to Change Physical Appearance
There are many products that can be spray dried, and some of those include beta carotene, cheese powders, juices, and seasonings. Beta carotene is an ingredient that has a red/pink hue that can present challenges for food manufacturers that do not necessarily want the color to impact their food or beverage product. So what can be done about this? Watson has developed a spray dried beta carotene product that, when dissolved in water, is clear! It’s called BetaClear® 768, and can tremendously help a food manufacturer to utilize beta carotene to meet Vitamin A claims without seeing a color impact in their finished product.
The Principles of Spray Drying
The basic principle of spray drying hinges on water removal, but how you remove that water can make a significant difference on the product’s overall quality.
Many factors must be considered when selecting the best method to produce your dry powder. A primary starting point would be to determine product moisture- and particle-size- requirements, as this will impact the atomizer choice.
Another factor to consider is the type of dryer you are using. If the dryer is a tall form dryer, then you have more surface area for drying, which will impact how product specs are achieved.
Upstream processing is as crucial to the spray drying process as the actual spray drying. Order of addition of raw materials will impact the viability of the emulsion or solution to be spray dried. Slurry temperature can also impact the viscosity of the material to be pumped. Too fast or two slow a pump rate can also impact how well the product dries in the spray dryer. If the emulsion is homogenized, the size of the micelle can also impact spray drying, along with shelf life in the future.
These are just some of the basic variables to look at when evaluating spray drying as a means to produce your powder.
Learn More
In a nutshell, no matter the application or the product, the spray process still involves taking a liquid slurry and removing water under heat to produce a powder. To learn more about the benefits and technology behind Spray Drying, attend our webinar on Septemeber 21st. Register here today.