Efficiency of a range of homogenisation technologies in the emulsification and stabilization of cream liqueurs

High-pressure homogenisers, including a Microfluidizer, an orifice nozzle homogeniser and a radial diffuser homogeniser, and an ultrasonic system were evaluated and compared in terms of their efficiency in model cream liqueur emulsification. As the size distribution of the fat globules after homogenisation is very important for product quality, influence of homogeniser type and processing parameters on the droplet size distribution were studied. The Microfluidizer homogeniser produced cream liqueurs with fat droplets of the smallest diameters, while homogenisation by an orifice nozzle or a radial diffuser homogeniser produced cream liqueurs with very wide volume frequency distributions of fat droplet diameters. For all high-pressure homogenisation processes, cream liqueurs with fat droplets of smaller mean droplet diameters were produced at higher pressures, and it was found that lower fat droplet diameters resulted in cream liqueurs with improved storage stability. Using the ultrasonic homogeniser, it was also possible to produce a cream liqueur with finely-dispersed fat droplets; however, problems during shelf-life appeared for highly processed samples.Industrial relevanceOther than typical dairy homogenisation processes, relatively few emulsification processes have been reported for the production of cream liqueurs. This work has important consequences in improving the efficiency of cream liqueur homogenisation processes and extending the shelf-life of cream liqueurs.

► Several technologies for emulsification of cream liqueurs were compared.
► Microfluidization yielded very small fat droplets and stable liqueurs.
► For all homogenisers, there was a relationship between homogenisation pressure and droplet size, and thus stability.
► Ultrasonic emulsification produced small droplets, but the process had to be tailored carefully to ensure stability.