i boil a big pot of water and collect the bottles through the day (only sterlised after each feed when baby was a newborn, but now use it for feeds within 3 to 4 hours), then dump it all in.
i do rinse the bottle with regular water after each feed, so that it is free of any residual milk. also, once they are ready to be sterilised, i clean with regular liquid soap and then add in the pot of boiling water.
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