Conclusions
In a highly competitive market, end-user involvement has become an
important factor in the product design process, as the sensory
interactions heavily affect their perception and the assessment of the
product. We have proposed an optimization-based methodology for the
design of formulated products, which incorporates the assessment of
consumer preferences along with available property models and heuristic
rules to generate alternative formulations. The methodology was
illustrated with two skin moisturizer products and using a commercial
product as a reference for each case. A series of alternative solutions
with minimum ingredient costs were generated and then manufactured and
evaluated. The alternatives generated taking into account the full set
of information, including the heuristics update from the consumer
assessment data, were shown to be more similar to the reference
products. The comparison was made through optical microscopy
observations, evaluation of rheological and textural properties, and the
measurement of the white residues left during rub-out.
As this methodology involves the participation of untrained consumers,
it is possible to reduce the time and resources spent in cosmetic
emulsions design compared with sensorial panels, as there is no panel
training involved. The methodology permits us to interpret the answer to
the products according to how they are perceived and calculate the
importance and the interaction of the evaluated attributes, which makes
it valuable to the formulator. This suggests that this is a useful
methodology not only to formalize the information about consumers’
perception of cosmetic products but also to guide the generation of
alternatives for other formulated products.