Cereals processing technology

the processes are similar to those for bulk fermentation in that a prolonged
period of fermentation is required to effect physical and chemical changes in the
dough. In this case only part of the ingredients are fermented – the sponge.
Sponge fermentation times may vary considerably, as may their compositions.
The key features of sponge and dough processes are:
• A two-stage process in which part of the total quantity of flour, water and
other ingredients from the formulation are mixed to form an homogeneous
soft dough – the sponge.
• The resting of the sponge so formed, in bulk for a prescribed time (floortime),
mainly depending on flavour requirements.
• Mixing of the sponge with the remainder of the ingredients to form an
homogeneous dough.
• Immediate processing of the final dough, although a short period of bulk
fermentation may be given.
The sponge contributes to flavour modification and the development of the final
dough. The process of flavour development in the sponge, though complex, is
observed as an increase in the acidic flavour notes arising from the fermentation
by the added yeast and other microorganisms naturally present in the flour. To
maintain the right flavour profile in the finished product the sponge fermentation
conditions are closely controlled and care is taken to avoid a build-up of
unwanted flavours. During the sponge fermentation period there will be a
decrease in sponge pH with increasing fermentation. Under these conditions the
rheological character of the gluten formed during initial sponge mixing changes
and the sponge becomes soft and loses much of its elasticity. The low pH of the
sponge and its unique rheological characters are carried through to the dough
where they have the effect of producing a softer and more extensible gluten
network after the second mixing. In many cases the addition of the sponge
changes the rheological character of the final dough sufficiently to warrant
further bulk resting time unnecessary so that dividing and moulding can proceed
without further delay.
Improver additions are commonly made in the dough rather than the sponge.
Flours used in typical sponge and dough production will be at least as strong as
those used in bulk fermented doughs with protein contents not less than 12% and
high Falling Numbers. High -amylase activity could be a problem in the
sponge because of excessive softening but is less likely to be a problem in the
dough.
10.4 The character of bread
Breadmaking 209
Bread is a staple foodstuff made and eaten in most countries around the world.
Bread products have evolved to take many forms, each based on quite different
and very distinctive characteristics. Over the centuries craft bakers around the
world have developed our traditional bread varieties using their accumulated