A yoghurt or a yoghurt drink is prepared by a method comprising: (a) providing a casein source that has been treated to remove a proportion of its divalent cations including at least a proportion of its calcium ions; (b) mixing the calcium-depleted casein source with one or more other ingredients to form a yoghurt milk, if required; (c) dispersing a substantially insoluble calcium source in the yoghurt milk; (d) heat treating the yoghurt milk; and (e) acidifying the mixture to a pH that causes gelling of the yoghurt milk. Step (c) is carried out at any time before gelling for set yoghurt and stirred yoghurt and the final packaging of drinking yoghurts.