The phrase 'cream off' implies taking only the most valuable or desirable portions from something larger. Investors often try to cream off the highest yielding stocks for their portfolios.
Pro Tip 2/3
Potentially Negative
Using 'cream off' may suggest selfishness or unfairness, as it can imply leaving less desirable parts for others. She creamed off the ripest fruit, leaving the bruised ones for the rest of us.
Pro Tip 3/3
Metaphorically Rich
Often used metaphorically to describe financial or qualitative selections in various aspects of life. The university tends to cream off the brightest students from all applications.