Property/Performance/Preference
Consumer Research
Linking Rheology to Consumer Experience
Often the objective of rheology testing studies is to correlate rheology behavior to consumer sensory perceptions and/or preferences. The rheology testing suite needs to capture how a consumer uses a specific product. What does the consumers intuit when they first see the product? What are the visual perceptions? Is there any difficult in dispensing the product? Is the viscosity or consistency correct for the intended packaging? These questions are important whether a consumer is handling paints, a personal or home care product, etc. The visual attributes are very important and can bias performance perception in a positive or negative manner. What range of shear rates needs to be covered during viscosity testing?
Knowing which rheology tests to select is the key to a successful property: preference correlation. This includes the design of the questionnaire to the final statistical analysis of the consumer and analytical data.
How Does It Look
and Feel?
Rheology is a strong factor in the physical appearance of a fluid or soft solid.
Overall consistency, stiffness, rigidity, and ability to keep its shape and form are related to mechanical property attributes. Some fluids maintain physical stability of a suspension while others do not throughout shelf life. Other products will appear quite solid-like in their packaging but deform easily with increasing stress or strain. Rheology is a key factor in the successful design and implementation of a product formulation.
How Easily Does It Pour, Spread, Extrude, or Spray?
Many consumer products will be poured, squeezed, sprayed, applied with a brush, or otherwise mated with some physical surface.
Products need to be dispensed by a broad range of users including kids, seniors, disabled individuals and adults. From an engineering perspective, this transient flow should be modeled for a broad range of potential users for maximum utility. Choosing the right test method to evaluate product behavior is of paramount importance. We choose these methods by keeping in mind the nature of the fluid and the objective of the test.
Rheology testing provides meaningful metrics in sensory studies of many consumer products including personal care and foods. Lubricity measurements can also be insightful into the “feel” of a lotion or cream as it is being applied. These metrics can quantify how easily it can be applied to the hands, face, or other parts of the body.
Substrate and Lubricity Considerations
Lubricity or dynamic coefficient of friction measurements, designed on the correct substrates, simulate actual in-use conditions by consumers. Ideally, these properties should be tested over an appropriate range of substrates to cover a wide range of consumers.
