Mixer studies should always be performed for the first production of a new product and randomly thereafter for essential nutritional parameters to ensure that vitamins, trace minerals, premixes and blends are being mixed as intended. Mixer studies can provide valuable information about how mixing procedures and/or formulas can be improved, such as:
- Substituting hand-add ingredients for ingredients added via a bin
- Altering when in the process an ingredient is added
- Adjusting the amount of mineral oil
- Modifying the ratio of carrier to active ingredients
- Changing the batch size
- Improving flowability
Mixer studies provide detailed data, including the average analysis; standard deviation, a measure of the amount of variation between samples; and coefficient of variation (CV), a statistical measure of the dispersion of data points around the mean for every component being tested. These measurements are compared to the expected average and the percent guarantee. A CV of five or less must be achieved for the test to pass.
The above-listed variables, and possibly others, are adjusted one at a time to improve the premix. After corrections are made, the mixer study is repeated until acceptable consistency is achieved.
A mixer study report includes every data point and graphically conveys how they vary.