Aller plus loin
∴ L’art de la fermentation, de Luna Kyung et Camille Oger
∴ Précis de fermentation, de Fern Green
∴ Ni cru ni cuit, de Marie-Claire Frederic
27 NOVEMBER 2016 | PAR SOPHIE RAOBEHARILALA
Fermentation isn’t as recent as we might think. In fact looking back centuries, Sumerians were the first to come across this process in 8000 B.C as they mastered fermentation to make bread and beer. Later on, Babylonians used palm wine to create wine in 5000 B.C. A recipe of fermented cabbage in wine was used in China as basic food for the builders of the Great Wall of China during 3000 B.C. Egyptian papyrus mention the use of fermentation as therapeutic with fermented milk and vegetables, characteristics which can be later found in first century Greece where Dioscorides cured infections with fermented red beetroots and sauerkraut.
A definition of fermentation suggested in the dictionary Larousse Gastronomique:
« Spontaneous or provoked transformation of certain food components, under the influence of yeast or bacteria. These micro-organisms are whether naturally present in food or added for production needs. The type of fermentation varies according to the type of food, the enzyme and the duration of the process, which leads to the creation of acids or alcohols: vinegar, lactic fermentation ( for milk, cereals or vegetables) or alcoholic fermentation.
The main fermented foods are raised dough, lactic products such as cheese, kefir, koumiss, yogurts; meat and drinks. The largest variety of fermented food can be found in the Far East for the diet of this part of the world in based on soya, rice and vegetables ».
Fermentation is used for food conservation whilst enhancing food quality and flavors. Fermented milk in the form of yogurt tends to be better digested by the organism and the CO2 emanating in bread production created by yeast gives a moister and lighter bread.
The process of fermentation and its use in cooking illustrates geographical specificities: cheese and bread are especially appreciated in Europe whereas in Africa it will be food based on fermented starch such as yam and manioc, and in Asia food based on soya such as miso in Japan, or food base on fish such as nuoc-mâm Vietnam which are regularly consumed.
After this brief historical world-tour of fermentation in international diets, we shall focus on Africa and the various use of fermentation around the continent.
In Africa, fermentation has a major role in food processing and conservation. Processed food improve their digestibility and are more attractive to the consumer. This food transformation also helps to have food stock in remote areas as well as outside of the food production period, thus stabilising supplies and increasing food security at national and household levels. A particularly important aspect of food processing is that it allows large diet diversity, giving consumers access to a wider choice of products. They also provide a better range of vitamins and minerals than they would usually consume. The most basic level of processing is food preservation, which has been practiced by families in traditional societies for generations in various forms to provide food when sources of fresh food were scarce. Village-based processing includes basic transformation activities such as milling. This type of processing, which can be done on an individual or group basis, provides employment for millions of rural people and is often one of the sources of income for rural women.
The preparation of gari, a dried fermented cassava product in West Africa and the smoking of fish in Ghana are examples of processed food, which transform highly perishable goods into products that can be transported long distances and stored. Cassava and banana may also be preserved by fermentation, followed by drying. In eastern Africa, cassava flour may or may not be fermented, and it is rarely consumed alone: the usual preparation is to add varying proportions of it to a cereal like sorghum or millet. Gari is produced at home in many Nigerian villages. The most common procedure is to harvest a few roots at a time so that they may be processed before they spoil. After cleaning and peeling, the roots are grated on a sheet of roofing iron roughened on one side by piercing with a large nail. The grated pulp is put into a cloth bag, which is tightly tied between wooden poles, and the bag is then set in the sun for the pulp to drain and to ferment. Heavy stones and logs are piled on top of the bag to press out the moisture. It is necessary to leave the grated roots under pressure for three or four days since drainage is slow. As a result, a certain amount of fermentation and souring occurs, which gives the product its characteristic flavour.
Cultivation of ensete (Ensete ventricosum), also known as « false banana », is limited to Ethiopia, where it is a main food crop of the people of the Gurage and Sidamo areas in the southern highlands.
The parts of ensete prepared as food vary from place to place, but they generally include the starchy portions of the pseudo-stem pulp (which may be boiled fresh as a vegetable), the young shoot, the trunk of the tuberous rootstock and in some cases the upper part of the root.
The young root may be cut up and cooked like a potato, but the other vegetative materials are usually pulverised and fermented in a type of silage pit for periods ranging from a few weeks to several months before consumption. The circular pits are lined with ensete leaves and filled with the starchy portions of the « stem », selected for fermentation. The top is covered with another layer of leaves and weighed down with heavy stones.
After three or four weeks the pit is opened and a starter from a strongly fermenting order silo is added to accelerate the fermentation. After a further period of several weeks the silo is again inspected and its contents are rearranged to give an evenly fermenting mixture. The ensete is ready for use after three to four months but can also be kept for one year or more.
Fermented food has therefore a very rich history and if its use in cooking has been maintained in certain parts of the world, it resurfaced in others. As well as providing healthy benefits and food stock to the consumer, we can see it has an essential role amongst communities for it takes part in social status in rural areas of Africa for instance. If fermentation tends to be a current new trend amongst food movements in the West with the introduction of Asian and African fermented ingredients in diets, it is more present than we think in the rest of the world, and actually in our European plates as well. This could lead to the generalisation of a remastered diet and food consumption with an exotic twist in these times of crisis.