Desem which means ‘leaven’ in Dutch, is a sourdough starter produced using whole wheat flour. It is essentially a traditional Pain au Levain (French sourdough). In fact, the original creator of Desem, Omer Gevaert, has referred to desem as bread made “in the old French manner.” The speciality of this bread is that no commercial baker’s yeast is involved in its preparation and it uses twice the amount of flour as water. This makes it stiffer in texture and the product is denser than other breads. The French are believed to have a strong distaste for sour flavour in their breads and hence bakers developed strategies to creatively mask this in spite of using sourdough as the starter which was the only leavening agent available at that point of time. Thus emerged the process of using desem. Over the years Desem has been traditionally employed in Belgium in order to yield nutrient dense, healthy and tasty bread.

The desem prepared traditionally needs to be stable and firm. Although 50 % hydration would have been ideal, it may be maintained at a hydration level of 60 % to enhance pliability. The environment where the desem is prepared also has to be maintained at a temperature of between 60 to 65 F and even lower if possible. The reason for maintaining such low temperatures is to enable the development of specific bacterial cultures different from those in normal sourdough. These usually consist of a live culture of naturally occurring wild yeasts, lactobacillus bacteria and fungi that act on the wheat flour in presence of water, ferment the dough, reacting with its starch to produce lactic acid and carbon dioxide. The released gas causes the dough to rise slowly over a period of time. The recipe for Desem uses freshly milled 100% whole wheat flour, 75% water, 2% salt in order to get the desired level of 60% hydration. In place of whole wheat flour, the spelt of flours like Amaranth or Kamut may be used along with water to make the desem.      

Desem needs to mature completely prior to use in bread making. Desem that is about three weeks old is considered mature. How does one know that the desem is mature? When it is fed with a little fresh flour and some water it turns spongy in a few hours. It seems to dissolve completely in water leaving no strings of gluten, thus indicating that it has aged sufficiently.  Bread made from a well matured desem is characterized by a strong rise, and boasts of a light texture, and has a nutty, slightly sour taste.

In preparation of the bread, the stiff starter i.e. the desem is dissolved in water and then salt is added. Once the salt is completely dissolved, the flour is slowly mixed in and kneaded until it is fully developed. This happens within about 10 mins. An initial rise happens within a time span of about 4 hours when held at normal room temperature. This 4 hour hold is important for development of optimum flavour and texture. After this the dough may be reshaped into a ball so as to have a somewhat tight casing on the outer side. This has to be done very carefully to prevent the gas bubbles developed within the body of the dough from escaping. This process is once again repeated after 15-20 mins, all the time ensuring that the inner layers of dough are undisturbed. The rounded ball of dough is then carefully placed in a bowl lined with baker’s linen or dusted with rice flour. After this, the shaped dough is subjected to one final hot rise. This step is recommended in order to obtain a lighter loaf which may be more flavourful and it also hastens the baking process. After an hour the heat treatment is repeated. The dough is checked after another 30 mins of resting. If it appears to have fully risen, it is ready for baking, if not another 30 mins or so of resting is advised.

The baking is performed employing steam at 450 F, after preheating for about an hour, for a period of 35-40 mins. Once baked, the loaf has to be set aside to cool on a rack for about an hour before it is sliced.

Special features of desem bread are-

• It is prepared in such a manner as to highlight the taste of pure wheat.
• Inspite of no added oil, it is moist, and stays fresh longer than commercial breads prepared using yeast.
• The raw bitterness and heavy texture obtained in many whole wheat breads are muted by using this natural yeast process without the need to add external agents like white flour, gluten, or conditioners.
• The inherent nutrition of the whole wheat grain is broken down and released into usable form by the bacteria.

Laurel Robertson, the famous cookbook author played a major role in popularising desem bread which has steadily gained favour among members of the natural foods community.