lipolytic products at the interface, which would have inhibited lipaseactivity, are likely to be responsible for the reduction in interfacialtension (Reis et al., 2010). Furthermore, Fig. 4B2 suggested that thecomposition of the aqueous phase, in particular the nature of the mixedmicelles, may have differed in presence of oil enriched in phytosterolscompared with the sunflower oil only. However, the dynamic eventstaking place at the interface could not be specifically identified with thependant drop technique. Indeed, it is likely that the process by whichphytosterols impact lipolysis is time dependent. The phytosterols mayaffect the ability of the bile salt micelles to remove the lipolytic products because the properties of the micelles change following the incorporation of phytosterols. Therefore, these micelles need time to formfirst before any effect of the phytosterols is observed. As a consequence,