An organised baby formula syndicate has swiped hundreds of thousands of dollars worth of formula tins from Melbourne's west with the intention of selling them overseas.

Police swooped on six separate properties in Sunshine, Sunshine West, Braybrook and Richmond on Thursday afternoon following a month-long investigation.

A detective carries a box of the stolen baby formula. Credit:Eddie Jim

Officers seized $300,000 worth of Aptamil formula, Swisse liver detox supplements and Lucas' Pawpaw ointment in addition to $500,000 worth of cash.

Detective Sergeant Mark Anderson said the thefts had an "organised element", with a number of the large companies noticing inventory was missing.