Merissa

What merissa is

Merissa (Arabic مريسة, marīsa; also spelled marissa, marisa or merisa) is a cloudy, sour, mildly alcoholic beer that Sudanese households and beer houses brew from sorghum, which Sudan calls dura. It belongs to the wide family of African opaque cereal beers, but its method is its own. Instead of one mash followed by one fermentation, the brewer prepares several portions of grain in different ways, some soured, some toasted, some boiled to a paste and a small share malted, and then brings them together through three linked fermentations.

The grain behind the best-documented method is feterita, a sorghum variety. Other sorghums can be used, and later reviews describe merissa made with millet. Millet covers several unrelated cereals, so no single species should be assumed for every batch.

What sets merissa apart from a European malt beer is how little of the grain is malted. In the method Hamid Dirar recorded in 1978, malt makes up about 5 per cent at the points where it is added, and its job is to supply starch-splitting enzymes rather than to provide the bulk of the starch. Most of the grain is soured or cooked first. That gives the brewer separate levers: sourness from the first stage, starch texture from the cooking, and yeast vigour from the starter.

The three stages have names. Ajeen is a sorghum dough left to sour. Once heated and toasted, the soured dough becomes soorij (also written surij), a dark, acid mass. Deboba is a strongly fermenting starter made from cooled soorij, malt and a little merissa from an earlier batch. The last stage, merissa fermentation proper, begins when cooked sorghum, called futtara, and more malt meet the deboba.

What reaches the cup is water, ethanol, organic acids, dissolved grain and fine solids that passed through the straining cloth. It is nothing like filtered lager. Published measurements put finished merissa near pH 4 and at roughly 5 to 6 per cent alcohol by volume, depending on the account. Those figures describe studied batches, not a standard, and the drink keeps changing after straining because the yeasts and bacteria are still at work.

Where it comes from

Merissa sits inside a long history of grain growing and grain fermenting along the Nile. Sorghum has fed people in the region for centuries as porridge, bread and drink. That background matters, but it does not date the particular three-stage method. Evidence that people brewed cereal beer is one thing; evidence that they made ajeen, soorij, deboba and futtara in the order modern researchers recorded is another, and the second is missing for the ancient period.

Classical writers describe grain drinks in the Kingdom of Kush, and a Meroitic graffito from Musawwarat es-Sufra shows figures drinking from a vessel through straws. Both show that cereal drinking is old in the region. Neither says what the drink contained, which organisms made it, or how. Archaeologists working on Sudan say this directly: beverages such as marisa have left little trace that identifies their recipes.

The nineteenth century brings the first specific records. Archaeological writing cites Burckhardt's account of 1819 and Cailliaud's of 1826 for Sudanese fermented cereal drinks. A traveller who journeyed in 1881 and 1882 drank merissa at Kassala, named dura as its grain and noted germination, milling, dough, cooking and fermentation. He disliked the taste, which tells us about him, not about how Sudanese drinkers judged it.

In 1925 C. B. Tracey published a short note, Merissa, in Sudan Notes and Records. It describes a low-alcohol cereal drink that served as a staple food for some communities, particularly in western and southern Sudan. Dirar then gave the drink its fullest documentation: The Art and Science of Merissa Fermentation in 1976 and A Microbiological Study of Sudanese Merissa Brewing in 1978, which set out the three stages and the different jobs of souring and alcoholic fermentation.

Dirar later placed merissa within a much larger body of Sudanese fermented foods. In a 1992 chapter for the United States National Research Council he explained that much of his information came from elderly rural women, and he stressed how much of this knowledge rests with them. FAO and UNIDO publications drew on his work to explain how Sudanese brewers combine lactic souring, cooking and enzymatic conversion. These twentieth-century records document a tradition. They do not show that merissa began then.

How it works

Two linked processes make merissa. First, sorghum starch is turned into sugars. Second, microbes turn part of those sugars into acids, ethanol and carbon dioxide. Starch is a mix of amylose and amylopectin, long glucose chains that brewing yeasts cannot ferment directly. Cooking opens the starch granules so water and enzymes can reach them, and germinated sorghum supplies the enzymes. The acid comes first and the alcohol later, from different stages.

Malting starts when soaked grain germinates and switches on the enzymes the seed uses to draw on its own reserves. Alpha-amylase cuts starch in the middle of its chains, giving shorter carbohydrates and dextrins, and other starch-degrading activities help produce fermentable sugars. Sorghum malt strikes a different enzyme balance from barley malt, so it should not be assumed to behave the same. Proteases free peptides and amino acids that feed the microbes and shape flavour.

Ajeen is the souring stage. In the moistened flour, lactic acid bacteria grow alongside yeasts and possibly acetic acid bacteria. A UNIDO account by Dirar stresses homofermentative lactobacilli, which turn glucose almost entirely to lactic acid. The acid lowers the pH, and the lower pH changes which organisms can grow next. FAO reports ajeen at about pH 4 with 1 per cent alcohol and 2.5 per cent lactic acid; the short FAO text does not explain the basis for the acid figure.

Heating the ajeen into soorij cuts the living microbial population sharply while keeping most of the acidity. It also browns the paste and produces toasted flavours through reactions between sugars and amino compounds. Soorij is then cooled and becomes the base of deboba, where malt and a little earlier merissa bring in enzymes and living organisms, so yeasts become active before the bulk of the cooked grain is added.

In the final fermentation, yeast turns sugar into ethanol and carbon dioxide. Reviews connect Saccharomyces yeasts with merissa, but the literature does not support naming one species or strain for every traditional batch. Lactic acid bacteria and yeasts remain in the finished beer. Its taste comes from lactic sourness, ethanol, leftover carbohydrate, heat-derived flavours and yeast by-products together, and it stays a living, unclarified drink, not a stable bottled product.

Why each ingredient and step matters

The method starts with sorghum and water. In the system Dirar recorded, part of the grain is malted separately: soaked for a day, left to germinate for two days, dried in the sun and ground to a coarse flour. Malting exists to build enzymes that will later break down cooked starch. These timings come from the one method he recorded and have not been shown to hold across Sudan.

The unmalted grain is ground to a fine flour and divided into thirds by weight. One third is moistened with just enough water to make a dough and left at room temperature for about 36 hours. That is ajeen, and its lactic acid sets the low pH that the later yeast stage will work in. The soured dough is then heated in a metal vessel and turned continuously until it becomes dark brown and strongly acid. Constant turning matters because it keeps any portion from sitting uncooked or scorching.

The other two thirds are split into two equal lots and cooked differently. One is lightly cooked to a greyish-brown paste and the other cooked further to a brown paste. They are combined and spread to cool as futtara. Heat makes starch granules take up water, swell and gelatinise, which is what lets malt enzymes work on them. Two degrees of cooking give a mixed texture and a staggered supply of accessible starch. Brewers work by eye and feel, not by thermometer or fixed ratio.

When the soorij has cooled, about 5 per cent malt flour, water and about 5 per cent merissa from a previous good batch go in. The mixture ferments for roughly four to five hours into deboba. Its purpose is to build a strong starter population in an acid medium: the old beer carries organisms, and the malt carries enzymes and nutrients. Deboba is very sour and is not meant to be drunk.

The cooled futtara is mixed with about 5 per cent more malt and added to the deboba in portions. Dirar notes that the cooked pieces are left to dissolve and not stirred in all at once, and that the malt enzymes liquefy the thick mass quickly. The final fermentation lasts about eight to ten hours. The mix is then strained through cloth. The liquid is merissa; the coarse residue, mushuk, goes to animals. Fermentation carries on after straining, so the beer changes while it is sold and drunk. No measured water volume or yield is recorded for the whole process.

Variations across Sudan and the grain belt

Merissa is not one standardised style. Sudanese cereal beers form a broad family whose names shift with region, language and period, and Dirar describes many opaque beers with different processing. The 1978 three-stage sorghum method is a detailed example. It is not a record of every drink ever called merissa.

Sorghum, and in particular feterita, is the principal grain in the well-described method. Millet is also reported. Grain choice affects colour, starch available, enzyme activity, protein and the texture of the cooked fractions, but no tested proportion for swapping millet in is recorded, so millet stays a reported variation, not part of the main method.

Accounts place merissa in several parts of Sudan: Kassala in the east, Kordofan and Darfur in the west, and western and southern Sudan generally in the 1925 note. These records need not describe identical methods. National borders have also moved since; South Sudan became independent in 2011. A shared name does not prove a shared method.

Other names turn up in the Sudanese literature, among them um-bilbil, baqaniya and bouza. Some refer to related cereal drinks or to grades, not to strict synonyms. Some are described as weak and others as stronger. One account of Sudanese fermented foods reports that in parts of northern Sudan a drink called merissa could be made with dates, which is a different thing from the sorghum beer described here.

Scale varied too. The 1978 study records family batches of about 2 to 4 litres and commercial brewing of 20 to 30 gallons. Equipment, stirring, heat, water and fermentation temperature differ with scale, which helps explain the spread in reported strength, sourness and thickness. A reconstruction today using cultured yeast, measured mash temperatures or commercial sorghum malt would be a modern adaptation, not the documented procedure.

How it is drunk and used

Merissa is both a drink and a substantial food. Because it keeps part of the grain it is brewed from, it is cloudy and has body, and the amount of solid in the glass depends on milling, liquefaction and straining. Descriptions treat it as closer to a nourishing grain drink than to a modern filtered beer.

In the 1978 study the beer is drunk soon after straining, while fermentation is still going. Dirar saw customers come to an indaya, a place where beer is made and sold, from sunrise to sunset. Merissa is not matured. It is made for almost immediate drinking, and its character shifts through the day: by late afternoon it can turn sharp and sour enough for customers to refuse it.

The plural of indaya is anadi, and these houses were also social places where people drank, talked and spent time. Brewing and selling gave income, especially to women, while brewing for the family was part of everyday food work. In some communities beer was tied to ceremonies, gatherings and hospitality. These roles varied by place and time and should not be read as one custom shared by all Sudanese communities.

Photographs from western Darfur in 1965 and 1969 show cereal beer sold by women from earthenware vessels and drunk from calabashes during communal house building. The beer in these photographs is the Fur millet beer kira, a different drink from the sorghum merissa described here. They show the social setting of cereal beer in Darfur, not this brewing method.

General research on African sorghum beers links their nutritional value to suspended grain, amino acids, yeast and B vitamins. That helps explain why merissa counts as a food, but it does not fix the nutrient content of any one batch, which depends on the grain, how much starch is converted and how much is strained out. The residue left in the cloth, mushuk, feeds animals. Historical accounts also mention aragi, a spirit distilled from fermented cereal, including strong merissa. Distillation is a separate process and does not belong in the brewing steps.

Reading results and problems

Merissa changes a great deal between souring, starter and final fermentation, so the brewer is judging several preparations, not one beer. Ajeen should turn sour, soorij should keep its acidity after cooking, deboba should ferment briskly, and futtara should liquefy steadily once it meets malt. These are observations from the traditional process. They are not tests of safety, and appearance, smell and bubbling cannot show that a batch is free of pathogens.

Soorij should be dark brown and sour. Underheated, it may taste different and keep more living organisms; burnt, it turns bitter. No colour scale or temperature is given in the primary description, so a modern recipe has to separate historical sensory cues from measured controls.

Weak activity in the deboba may point to a poor inoculum from the old batch, a cold room, too little accessible nutrient or contamination. These are possible causes, not a diagnosis. If the final mixture stays thick, the grain preparation, malt activity and heating are the places to look, though the traditional record gives no viscosity target and no corrective quantities.

Acidity and alcohol are useful for comparing published results. The Liege review reports finished merissa at about pH 4 and about 5 per cent alcohol by volume, and FAO describes about 6 per cent. They come from different summaries and are not limits or proof of safety. A pH meter says more than taste does, and a lively fermentation does not show that acidification came early enough to hold harmful organisms back.

Keeping quality is poor and well documented. Traditional sorghum beers are drunk while still fermenting and spoil fast because yeast and bacteria remain in the liquid. More acid, shifts in aroma, sediment and more ethanol are expected after straining. A batch that is visibly mouldy or putrid should be thrown away, not strained or reheated, and a clean smell does not rule out every hazard.

Grain quality matters too. A 2018 study of sorghum from Burkina Faso, Ethiopia, Mali and Sudan found aflatoxins, fumonisins, sterigmatocystin and other mycotoxins in part of the grain. Sudanese samples had the lowest prevalence of the four countries but were not free of them, and such toxins can survive cooking and fermentation. Sound dry grain, clean water and clean equipment are essential. The historical method is not a validated food-safety protocol, and without measured quantities and microbiological limits, a reconstruction meant for others to drink would need its own validation.