Powder Flow Testing

A powder flow tester (PFT) measures flowability, or ability of feed ingredients or premixes to flow during handling.

Pet parents expect that when Fido eats his dog food, he’s receiving the ingredients and nutrients identified on the back of the bag and in the quantities specified. If, however, his pet food was developed with an inconsistent premix, he could possibly miss out on his daily requirements for a vitamin or mineral or even receive too much of a vitamin or mineral, which in excess, can cause illness and in rare cases, even death. To ensure Fido receives the vitamins and minerals he needs in the proper amounts, premix consistency is key.

Particle Size Determination
Particle size can influence vitamins’ stability, the ability of the nutrient to retain its physical state, chemical structure, composition and/or properties. The smaller the particle size, the larger the surface area, the greater exposure to adverse agents, such as minerals and moisture. The increased surface area can magnify hygroscopicity, the ability to attract or absorb moisture, and its solubility, its ability to dissolve.

To ensure the premix achieves a uniform and adequate level of dispersion to meet Fido’s daily requirement, Trouw Nutrition uses a powder flow tester (PFT) to determine the handling characteristics of each ingredient.

Handling Characteristics
Proper manufacturing of a homogenous pet food premix requires it to flow freely between bins, hoppers, mixers and into the final bag. Obstruction of flow between any of these vessels could impact production time and raise expenses. To optimize handling characteristics, a PFT analysis measures a premix’s:

  • Flowability (ability of feed ingredients or premixes to flow during handling)
  • Bulk density (a measurement of the weight of a given volume)
  • Wall friction (the amount of friction between a powder and a given wall surface)
  • Compressibility (a measure of the change in volume resulting from the application of external pressure)
  • Normal stress (stress applied perpendicularly [i.e., normally] to the sample)
  • Shear stress (stress between parallel layers of ingredients or between a layer of ingredient and the PFT sample lid)

Our formulators can use this information to adjust composition and prevent flowability issues. PFT measurements can also be used for benchmarking, in which a single sample result is compared to the historical data set of all ingredients and premixes to identify significant differences. Similarly, we can use PFT measurements to aid the development of new formulations; new ingredients or blends can be compared to the historical data set to gauge how it will handle based on previous measurements.

To maximize the consistency and performance of your premixes with PFT analysis, contact your Trouw Nutrition representative, call 800.365.1357 or email info@trouwnutrition.com.