I have expressed milk before so that when I am out, someone else can feed DD. Usually I express and leave the milk sealed but out in room temperature surroundings, as DD will have a feed within 2-3 hours of the milk being expressed.

I know that breast milk will last longer if refrigerated, my question is whether refrigerated milk the needs to be warmed up before being fed to DD, and if so, what temp does it need to be?