The only thing that's frequently drunk in Sudan is tea.
Tea & Coffee in Sudan
Islam is in charge here , so the only thing that's frequently drunk in Sudan is tea; usually sweet and black. Hibiscus tea called Karkadeyh (red) is a delicious alternative. Sudanese coffee is available in most souks and is similar to Turkish style coffee; thick and strong, sometimes flavoured with cardamom or ginger with a powerful kick and altogether delicious. Not to be taken before bed though if you want an undisturbed night's sleep! The general advice is not to drink tap water; in most rural areas you will not be able to, as there are no taps... Where there are no bore holes (which often yield water that is fine to drink), water is often taken directly from the Nile. Fresh fruit juices are available throughout Sudan. One of the local juices is "aradeab".
Alcohol in Sudan
However while Alcohol is strictly illegal in the Muslim north (but not in the semi-autonomous non-Muslim south) locally brewed alcohol is widely available in various forms and at various degrees of potency. A local beer (merissa) brewed from sorghum or millet is cloudy, sour and heavy and likely to be brewed with untreated water and will almost certainly lead to the 'Mahdis' revenge' (the Sudanese version of 'Delhi belly'). Aragi is a pure spirit distilled from sorghum or in its purest form, dates. Potent and powerful it should be treated with respect and is sometimes contaminated with the likes of methanol or embalming fluid (!) to add flavour and potency. Be aware though that all these brews are illegal and being caught in possession can result in the full implementation of Islamic law punishments. In the towns of south Sudan such as Rumbek and Juba, Kenyan and Ugandan beers are starting to appear in bars at inflated cross-border prices.