Not
every person can eat what they like; far from it,
one in every 250 people in Germany is intolerant to
the protein gluten, which is chiefly found in the
cereals wheat, spelt, barley and rye. Experts call
this intolerance coeliac disease. For those affected,
this means giving up bread, pizza, pasta and cakes,
while ice cream wafers, dumplings and pretzels also
pass onto the list of banned foods. Those suffering
from coeliac disease, a chronic bowel disorder, must
keep to a strict diet if they are to avoid diarrhea,
stomach ache, vomiting and other symptoms.
Accordingly, only gluten-free products make it onto
the menu.
Indeed, demand for these
food products, mainly offered by small and
medium-sized enterprises (SMEs), has risen steadily
over the past years. Nevertheless, many consumers
dislike gluten-free pasta and bakery products
because they are unappetizing, lacking in texture
and leave a disagreeable sensation in the mouth.
This is a view confirmed in consumer tests involving
coeliac disease sufferers and healthy volunteers.
The tests form a key part of the EU project
GlutenFree, which is being coordinated by the
Fraunhofer Institute for Process Engineering and
Packaging IVV in Freising. Partners include
ingredient providers and food producers as well as
research institutes from Germany, Ireland, Italy and
Sweden. The aim of the project is to enable SMEs to
develop premium, tasty gluten-free products that the
consumer will eat with real enjoyment and
satisfaction. The focus is primarily on bread and
pasta, and on improving their taste, smell,
appearance, texture and sensation in the mouth.
Gluten is good for
baking because it holds the dough together. “Gluten
contains two protein fractions, the gliadins and the
glutenins. These form a network-like structure – the
dough matrix, if you like – giving the dough good
porosity and a viscoelasticity that allows it to
keep its shape and remain elastic in the baking
process”, says Dipl-Ing. Jürgen Bez, scientist at
IVV.
Gluten-free bakery products dry out more quickly,
crumble more easily and have a shorter shelf-life.
Pasta without gluten overcooks more quickly, and is
sticky and less elastic. “As a result, finding
ingredients to compensate for gluten’s positive
properties is a challenge”, says Bez. The process
begins as early as the selection of raw materials:
quinoa, for instance, often produces a bitter taste.
Nevertheless, researchers have been successful in
finding ingredients such as plant proteins, which
lend pasta and bakery products the same structuring
effect as the protein gluten. Hydrocolloids like
xanthan gum, HPMC and dextran have all been examined
carefully, as well as seeds taken from cereals and
pseudocereals like amaranth, quinoa and buckwheat.
In addition, scientists analyzed protein isolates
taken from potatoes and pulses like lupins, broad
beans and peas, as well as investigating the
interaction of a variety of recipe ingredients
during the production process, and the ways in which
this affected texture, sensory properties and aroma
profile. A whole range of recipes were tested; for
example, researchers combined proteins with soluble
fibers like xanthan gum and HPMC or with insoluble
citrus fibers.
It’s the combination
that counts. “Adding the hydrocolloid xanthan gum
succeeds in giving dough a particular elasticity,
though here the end result is heavily dependent on
the concentration, the proportion of water, the type
of flour and the other ingredients. Getting the
right combination is crucial”, summarizes Bez. “As a
rule, hydrocolloids alone are not enough to offset
the lack of gluten, and proteins need to be added to
recipes.” Thanks to a special production technique,
scientists are able to extract a protein isolate
containing viscoelastic properties from the seeds of
lupins and broad beans. This was another technique
developed by Bez and his team at Fraunhofer IVV. “By
adding lupin proteins, we were able to improve the
volume of baked goods”, says the researcher.
Scientists also established that adding sourdough
helps prevent loaves from going moldy so quickly,
observing that dough becomes more elastic and that
loaves stay fresh for longer. What’s more, some
gluten-free flours are more nutritious than wheat
flour. Test subjects rated oatmeal, rice flour and
teff flour particularly flavorsome.
Bez considers the
project a success, pointing to project partners’
success in producing a range of new and improved
gluten-free breads, including toast bread, leavened
bread and oat wholemeal bread, ciabatta, baguettes
and pizza dough. Four of the baked goods producers
involved in the project are already using the
recipes for ciabatta, wholemeal bread and pizza
dough. Furthermore, researchers were able to produce
tasty, gluten-free spaghetti with a high fiber and
protein content. Bez is confident that it won’t be
long now before we see some of the new products
lining bakery and supermarket shelves.
For more information
http://www.glutenfree-project.eu/
http://www.fraunhofer.de/
( MDN )
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