The power of powders in nutraceuticals
Powders play a key role in the nutraceutical industry, offering unique benefits. They are versatile and can be incorporated into various galenic forms – such as sachets, granules, tablets, capsules, and beverages – making them an ideal choice in product development, ensuring both flexibility for manufacturers and ease of use for consumers. Additionally, powdered botanical ingredients preserve the full vegetal matrix, retaining all natural constituents and improving the bioavailability and efficacy of active ingredients through the synergistic potential of phytoactives. Processing techniques like spray drying further enhance the stability, solubility, and shelf life of powdered ingredients, ensuring their long-term efficacy. Compared to liquid formulations, powders have a lower risk of microbial contamination and a longer shelf life. Their concentrated nature and lower weight can also make them more cost-effective to produce and transport, resulting in potential cost savings for both manufacturers and consumers.
Overcoming flow and caking challenges
However, powders present challenges in both industrial and home conditions. Due to particle interactions, they may flow poorly and cake over time, leading to manufacturing disruptions. For example, powders that flow poorly or cake can cause uneven mixing, leading to content uniformity issues. They may also clog dosing systems, resulting in costly downtimes for cleaning. Additionally, they may cause inconsistent die filling resulting in unacceptable variations in tablet and capsule weight, as well as defects such as tablet capping or lamination, or both. Further, working with challenging powders can cause excessive wear on equipment due to sticking and clogging, while also creating complications in packaging and downstream powder management.
The challenges associated with powders stem from the interactions between their particles. Factors such as surface roughness which increases friction, irregular particle shapes that lead to mechanical interlocking, electrostatic charges that cause particles to clump, or surface moisture that results in adhesion through capillary bonding all contribute to poor flow and caking.
Incorporating glidants and anti-caking agents
Because each powder behaves as a distinct and intricate matrix, these issues are difficult to manage. While process interventions such as vibrating equipment or temperature and humidity control can address some of these challenges, they are often costly, inefficient, and insufficient. The most widely used solution for improving flow and preventing caking is the incorporation of glidants and anti-caking agents. These ingredients reduce friction and mechanical interlocking by smoothening the surface of the base powder particles, decrease cohesion by coating them, and prevent adhesion by absorbing moisture. (Figure 1)