More organic, tasty bread with VTT’s method
VTT has developed a method whereby the use of additives in bread can be
reduced significantly. At the same time, the taste and lightness of wheat
bread made using sourdough, and keeping it soft without chemical additives,
can be greatly improved. The method is based on lactic bacteria, which produce
hydrocolloids during the sourdough fermentation and which are useful in terms
of baking technology. VTT identified the useful lactic bacteria in a survey in
which over 100 cereal and food-based microbes were screened. Corresponding
safe microbes, i.e. starters, are used in making yoghurt and sour whole milk,
for instance.
Baking tests demonstrated that the hydrocolloids produced in sourdough
facilitated the mechanical processability of the dough, improved the shelf
life of wheat bread and increased its volume. The quality of the bread was
even better than that of ordinary leavened bread: the taste was mild and there
was no strong pungeant taste typical of bread made from sourdough.
Starters
are used in the production of foods in which fermentation is one of the
manufacturing stages. They offer a wealth of opportunities for shaping the
structure, taste, healthiness and safety of the product. VTT’s research
focused on starter populations that under suitable conditions generate
hydrocolloids, and saccharates that gel, i.e. exo-polysaccharides. These are
used as food coagulants and emulsifiers, sources of fibre, fat substitutes and
bread improvers, for example. Their use is indicated by an E code on packages.
The
production of hydrocolloids in the sourdough improves the already known
positive effects of sourdough fermentation in baking. The technology offers
opportunities for making increasingly organic bread, enabling the use of
E-coded additives, such as refined hydrocolloids, to be reduced considerably
or replaced altogether.
Even the use of ordinary sourdough
usually improves the nutritional qualities of wheat bread e.g. by slowing down
the digestion of wheat bread (low glycaemic index) and raising bread folate
concentrations. The production of hydrocolloids in the sourdough makes it
possible to greatly enhance the health-promoting effects of sourdough.
The
technology also offers opportunities for producing ingredients for making new
types of cereal products and foods. In addition to bakeries, the technology
can be utilised by starter producers and other food industries.
The
new technology was generated in a project entitled Tailor-Made Sourdough
Fermentation for the Improvement of the Structural and Nutritional Properties
of Cereal Products, which was conducted together with the University of
Helsinki and the Finnish bakery industry. The main financiers were the Finnish
Funding Agency for Technology and Innovation Tekes, and VTT.