Turn milk is "old and new mixed": the parents prepared to replace the milk powder
and baby milk to drink earlier in the turn to drink milk when blending, as in the original formula used by the appropriate add new milk powder starting point can be is less, and slowly increase the proportion of appropriate until the full replacement. For example: the old milk in first to add 1 / 3 of the new formula, so no not to eat two or three days, then the old and new milk powder and 1 / 2 to eat two or three days, then the old 1 / 3, new 2 / 3 of eating two or three days, and finally the transition to a completely new formula to replace the old formula.