Milk fat?

Di

I’m breastfeeding and pumping and notice that when I pump and refrigerate my milk some of it is kind of clumped along the outside of the bottle when I go to retrieve it. I usually transfer into a different bottle to feed the baby and that milk gets left in the bottle. Should I be shaking it to try to remove that? I’m just worried he’s not getting enough fat in the milk as he is always hungry although he is gaining appropriate weight.