A trade-off, in biology, is defined as a constraint that link two traits. Improving one trait has a negative impact on the other trait. While there is an increased interest in trade-offs, and their roles in shaping the traits of organisms, it remains difficult to demonstrate their presence and relevance in lab experiments. To study a trade-off between yield (biomass production per resource) and rate (biomass production over time), we conducted an experimental evolution study with Saccharomyces cerevisiae in an emulsion culture that has previously been shown to select for yield (Bachmann et al, 2013). We observed that 5 of our 6 lines increased in growth yield during evolution. While this increase was not correlated with a decrease in growth rate, our study allowed us to uncover other adaptations. Genomic analysis of the ancestral and evolved lines provided further insights into the evolutionary response of S. cerevisiae to selection in the emulsion environment.