Enhancing the sensitivity of emulsion stability monitoring: A study based on precursor signals from multiple light...

To accurately identify early destabilization signals in emulsions, this study employed multiple light scattering (MLS) technology combined with microscopic observation, particle size analysis and long-term macroscopic stability tests to perform a multi-scale evaluation on a series of emulsions. By comparing the migration of the transmission light inflection point, the average rate of change of backscattered light intensity (BS_MRC) and the uniformity index (U) of samples under different temperatures, the intrinsic correlation between MLS signals and emulsion stability was systematically analysed. The results indicated that three typical destabilization phenomena can be predicted based on the characteristics of the inflection point changes. Further dynamic tracking of BS_MRC and U revealed that for stable samples, both BS_MRC and U remained at low levels. During destabilization at high temperature (45°C), a significant increase in BS_MRC served as a precursor indicator of phase separation. During destabilization at low temperature (-16°C), the U value markedly increased while BS_MRC changed gradually, reflecting mechanical damage induced by freezing. In conclusion, multiple light scattering technology can capture destabilization signals in emulsions in advance, with sensitivity superior to traditional visual observation, thereby providing an efficient and reliable technical approach for formulation screening and long-term stability prediction of emulsions.