Amasi is traditionally prepared by storing unpasteurised cow's milk in a calabash container (Xhosa: iselwa, Zulu: igula) or hide sack to allow it to ferment. A calabash is smoked, then milk from the cow is put in a skin bag or bucket, where it ferments for 1 - 5 days, and acquires a sharp acidic taste. The fermenting milk develops a watery substance called umlaza, 'whey'; the remainder is amasi. This thick liquid is mostly poured over mealie meal porridge called pap (Xhosa: umphokoqo). It is traditionally served in a clay pot and it can also be drunk.
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