Flourpedia.com - Gluten strength is an important factor in bread baking performance. It contributes to the ability of dough to rise and maintain its shape as it is baked.
Gluten
composition
There are
several types of proteins that make up the total protein content in cereal crops,
one of which is gluten. Gluten is a protein composite that accounts for 75 to
85% of the total protein content in bread wheat. Gluten component proteins are
found in the endosperm of mature wheat grain, where they form a continuous
framework around the starch granules.
Gluten is
comprised of two protein groups: glutenin and gliadin. Glutenin contributes to
the elasticity of gluten while gliadin contributes to extensibility. A balance
between elasticity and extensibility is necessary for superior baking performance.
Gluten
functionality in bread making
Gluten proteins
are the most important protein group in bread making. Gluten forms when water
is added to flour and is mixed. During mixing, a continuous network of protein
forms, giving the dough its strength and elasticity. By holding gas produced
during fermentation, the protein network allows bread to rise. It also allows
the dough to maintain its shape. These two functions of the protein network are
what give bread its chewy texture.
Factors
affecting gluten performance
There are
several factors that can affect gluten performance.
Gluten strength
is different in all varieties of wheat. The differences are caused by the
unique number and combination of glutenin and gliadin polypeptides in each
wheat variety, resulting in varieties with slightly better gluten strength than
others. Bread that is baked using a “better” quality variety may have a higher
loaf volume than bread baked with a “lesser” variety, even when both varieties
have the same protein content.
Environmental
conditions during the growing season can also have a large impact on gluten
strength. Excessive rainfall, especially early in kernel development and during
grain filling, can have a negative impact on gluten strength. Likewise, heat
stress or frost prior to full maturity can halt formation of gluten protein
components, resulting in weak dough properties. Some varieties are affected
more by environmental conditions than others.
New varieties of
Canadian wheat intended for bread making undergo three years of rigorous
testing for their agronomic performance, disease resistance and end-use quality
performance prior to being registered. There is a range of acceptable gluten
strength within each class of wheat, and all new varieties must fall within
that range during the three year test period. Once registered, they can then be
delivered and sold as milling quality wheat.
Predicting
milling and baking performance
When millers and
processors buy Canadian bread wheat, they have expectations about how that
wheat will perform when it is milled and baked. Wheat is visually inspected for
a number of grading factors which predict how wheat will perform. The effects
of these factors on milling and baking performance are known and predictable
because of scientific study. Furthermore, because registered Canadian wheat varieties meet end-use quality performance criteria, visual assessment for
physical damage is an effective means of classifying and grading wheat.
Title : Gluten Strength
Originally Publish At : www.thebbqbaker.com
Post a Comment