How do I avoid agglomeration during mixing?
Agglomeration is the co-growing / clumping of product particles. This happens especially when liquids and / or fats are present or added to a powder. This can be deliberate or an unwanted phenomenon.
If liquids are added, the size of the liquid droplets with which the powder comes into contact is important. If a liquid droplet is so large that several powder particles adhere to / in it, a lump will form. It is therefore important to spray small liquid drops. In addition, active mixing and correct liquid dosing time are important. Liquids take time to penetrate the core of the product. If this happens too quickly, the liquid will partly remain on the surface of the product, causing a snowball effect; other product parts grow on the sticky product, resulting in more and larger agglomerations.
With fats or viscous products, the temperature of liquid and product is also important. If a lump develops and it has cooled, it will not fall apart quickly. Lecithin, a commonly used additive in the food industry, requires higher temperatures of 55 ° C to 80 ° C in some cases.
The speed of mixing also has an influence. Applying liquid to floating / passing product has great advantages compared to adding liquid to slow moving product. A paddle mixer is therefore very suitable to prevent agglomeration. The paddle mixer moves the products by fluidization through the drops of liquid, causing the drop to break.