Why does boiling milk overflow, but boiling water does not?
● The major component of Milk is water (83%). Its other constituents are protein
(5%), sugar (5%) and fat (7%).
● When heated, fat is lighter than water floats as a creamy layer on the top and
water vapor in the form of steam bubbles is trapped under it.
● Further heating results in the formation of more bubbles These
bubbles expand and lift the creamy layer, causing it to overflow.
● You can prevent the boiling over the problem by lowering the heat.
● In the case of water, the steam bubbles breathe as they reach the surface. So boiling
water does not overflow.