Rheolaser Crystal analyzes phase transition of complex materials containing oils, fat, waxes, polymers… It directly measures smallest change (nanometer scale) in microstructure during phase transition. Thanks to the non-invasive optical method, a precise and sensitive study is possible. Measuring the structure on a macroscopic sample (from 0.05g to 5g) overcomes general issues with sample heterogeneities. It also reduces the risk of damaging the structure during the sampling. Temperature cycles and accelerated aging tests can be performed thanks to fast temperature control. This is particularly interesting when characterizing finished products like oil formulations, lipsticks… to detect at early stage fat exudation, polymorphism, or even chocolate blooming.