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Amasi (so called in Zulu and Xhosa, and "maas" in Afrikaans) is the common word for fermented milk that tastes like cottage cheese or plain yogurt. It is very popular in South Africa. Amasi is traditionally prepared by storing unpasteurised cow's milk in a calabash container (igula in isiZulu) or hide sack to allow it to ferment. The fermenting milk develops a watery substance called umlaza; the remainder is amasi. This thick liquid is mostly poured over the mealie meal (maize flour) porridge called pap, or drunk straight. It is traditionally served in a clay pot (ukhamba in isiZulu) and eaten with wooden spoons. Amasi is also produced commercially using Lactococcus lactis subsp lactis and L. lactis subsp cremoris
AMASI IN SOUTH AFRICAN CULTURE
Traditionally, Zulus believe that amasi makes a man strong, healthy and desired. During taboos (e.g. menstruation or when there has been contact with death) the affected person must abstain from amasi. Milk is hardly ever drunk fresh ('green milk'), but it is sometimes used to thin amasi which has gone too thick to be used.
The Zulu expression kwafa igula lamasi translates to the calabash of sour-milk broke, i.e. our last hopes were dashed.
Nelson Mandela mentions how he cautiously left a comrade's apartment—his hiding place in a white area when he was wanted by the Apartheid government—after he overheard two Zulu workers comment that it was strange to see milk on the window sill (left out to ferment) because whites seldom drank amasi.
It is also popular in South African Indian cuisine where it is used similarly to curd.
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