11. Possibilities of
Influencing Milled Rye Products
In the past, baking technology was directed solely towards combating
sprouting. We have to take this into account when reading older literature and
the recommendations such works give. In many cases out-of-date recommendations
have been accepted without further thought for processing today's milled
products.
In recent years, millers and bakers have gladly accepted improved raw
materials and integrated them into their quality systems with correspondingly
adjusted data. For example, the standard values for Falling Numbers and/or the
Amylogram most often used for characterizing the value of the product for
processing have constantly been raised. Because of this, lots with balanced
enzymatic effect were often rejected, or the mills had to treat the flour in
order to achieve the values stipulated in the contract. It was found that
treatment of the flour with enzymes can change the Falling Number and Amylogram
data, but it does not necessarily have a positive effect on baking properties.
Rye with "natural" Falling Numbers between 120 and 150 s usually
produces the best results, provided that the dough does not soften too much.
Even now, many bakeries still use multi-stage sour-dough processes,
whatever the reason may be. Such processes used to be a reliable way of
achieving good bread quality with highly enzyme-active milled products that
break down readily. In these and some other sour dough processes, work is
carried out in single steps with large quantities of starter (30% or more). The
very acid conditions when a new sour dough starts to ferment reduce enzymatic
conversion.
Milled rye products need sour dough to this day, not necessarily to
achieve an even, elastic crumb but chiefly to form flavour components or their
precursors, i.e. to enhance the taste of the bread. It is still not possible to
separate acidification from flavour synthesis in the sour dough. Since the sour
is so important as a source of flavour, the pre-doughs used should be correspondingly
reactive. In order not to overdo acidification, it is advisable to work with
sour doughs made overnight with a moderate proportion of starter and with a
relatively low starting temperature and a high dough yield.
We therefore recommend one-stage sour-dough processing with:
• 5 to 10% starter (based on the amount of flour or meal in the sour
dough);
• a dough yield of about 180 - 200% (or higher if it is to be pumped);
• an initial temperature not exceeding 25 °C in the sour dough;
• fermentation times of 14 - 18 h.
Although this sour dough should be used within one day of being
prepared, it can be kept for up to 48 h without refrigeration if its
temperature does not exceed 28 °C. If this presents a problem in the hot summer
months, it is advisable to start at a somewhat lower temperature or to use the
sour dough within 8 to 12 h of its maturing or to refrigerate it after this
time. Bread doughs should be processed as soft as the dough properties allow,
and the temperature should be round about 28 °C. The quantity of yeast should
be no more than 0.5 to 1.0% in rye bread and about 1.5 to 2.0% in mixed wheat
and rye bread to achieve good leavening without too rapid fermentation. The
amount of yeast needed naturally depends on the resistance of the yeast to
acid, which means that the above figures are only a guide.
When rye flours that break down readily are baked, it is not necessary
to make changes to the dough processing steps (including shaping) and
fermentation. If only a small amount of yeast is added the dough resting time
is slightly longer, but the final fermentation time can usually stay as it is.
To achieve a soft, moist crumb it has proved an advantage to choose a hotter
and slighter shorter baking regime or to make hearth bread or pan loaves.
Acidification measures, dough yield and the baking regime remain the most
important criteria for achieving a properly elastic crumb that is not too moist
and does not roll into a ball – i.e. pleasanttasting, moist bread with a good
shelf-life.
12. Summary
The aim of this contribution is to show how important the properties
of milled products are even during preparation of the dough. It includes
references to characterization of the rye, not only on the basis of its
behaviour during the hot phase of baking but also in the cold phase, i.e.
during the dough processes. The Rye Viscosity Test may be recommended as a
simple method of describing the dough properties of rye for baking purposes
more reliably, with emphasis on bread and other small baked products leavened
with yeast and/or sour dough.
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