Pumped breast milk should be refrigerated immediately as it's summer now. u should store it in a covered and sterilized toxinfree plastic container. U can store the milk for a week in a fridge(u can write the date on the container to avoid confusion ) . The stored milk should be warmed before it's given to baby. But once warmed u cannot refrigerate the milk again. <br> Nan pro and similac are the popular brands of infant formula milk. But it's best to consult with a doctor before starting formula milk.