Why do functional ingredients need delivery systems?
In general terms, bioactive food compounds, nutraceuticals or functional food ingredients are usually very sensitive to certain environmental conditions such as temperature, light and oxygen. These conditions are not only part of industrial processes but are also present in the gastro-intestinal tract due to enzymes or other nutrients. In other words, degradation of functional ingredients can be caused by chemical, physical or biological agents that may be found in the early stages of production and incorporation until the storage and consumption of the enriched foodstuffs with those ingredients. Consequently, bioactive compounds need to be protected so that both their properties and bioavailability remain unaffected by such conditions, hence preserving the effectiveness of functional foods that contain them.
Delivery systems therefore are designed to protect these sensitive ingredients, and may also improve their bioavailability. As such, delivery systems should protect the functional ingredient during processing, storage and utilization of the functional food. Also, functional delivery systems should be compatible with other components of the food matrix, and that they have no undesirable effects on the physicochemical and sensory attributes of the enriched product.
In addition, certain functional compounds are not soluble in the food medium that needs to be enriched, for example, hydrophobic compounds that are used to enrich an aqueous beverage. Therefore, the delivery system is very important to help solubilize and carry the functional ingredient.
Finally, growing importance is being attributed to the controlled release of the active functional compound and so, a vehicle may also be required to control the release rate and respond to the particular environmental conditions that may trigger release (e.g. pH, ionic strength or temperature).
