The perfect way of producing gluten free products

1. 1
CHALLENGES ASSOCIATED WITH PRODUCTION OF
GLUTEN FREE BAKED PRODUCT: WAY FORWARD
BY
UKORO FRANK O.
UMM/PG/FST/M.sc/017/021
Quote the author: Ukoro Frank O. (Author), 2018, How to ProduceGluten-Free
Biscuits. Production-Challenges and Potential Solutions, Munich, GRIN
Verlag, https://www.grin.com/document/507417.
COLLEGE OF FOOD SCIENCE AND
TECHNOLOGY
DEPARTMENT OF FOOD SCIENCE AND
TECHNOLOGY
UNIVERSITY OF MKAR, MKAR
MAY, 2018

2. 2
CHALLENGES ASSOCIATED WITH PRODUCTION OF
GLUTEN FREE BAKED PRODUCT: WAY FORWARD
BY
UKORO FRANK O.
UMM/PG/FST/M.sc/017/…
SEMINAR SUBMITTED TO
DEPARTMENT OF FOOD SCIENCE AND
TECHNOLOGY IN PARTIAL FULFILLMENTS
OF THE REQUIREMENT FOR THE AWARD
OF MASTERSDEGREE IN FOOD SCIENCE
AND TECHNOLOGY
UNIVERSITY OF MKAR, MKAR

3. 3
MAY, 2018
DECLARATION
I declare that except where literature has been cited in this research work, this
research is written by me and it is record of my own work.
Ukoro Frank O. ________________________________
UMM/PG/FST/M.Sc/17/… Sign /Date
APPROVAL PAGE

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This work has been read and approved as part of the requirement for the award of
M.Sc in Food Science and Technology.
Dr. P.I Akubor ____________22/4/2017____________
Supervisor Sign/Date
Mrs. M.O Ojo _________22/4/2017_______________
SeminarCoordinator Sign/Date
ProfessorA.I. Ikeme ________30/4/2017_______________
HOD. Food Science, Technology Sign/Date

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DEDICATION
I dedicate this piece of work to my family member friends and coursemate.

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ACKNOWLEDGEMENTS
With colossal gratitude to God’s hands of provision, preservation and protection
upon my studies. Nothing could have been achieved without his grace and
providence.
I would like to thank those that have contributed in various ways to ensure the
success of this work during the defense.
The same greetings go to the head of department and entire lecturers in Food
Science for impacting knowledge and criticism.
Finally I thank Dr. Akubor P.I for taking much of his time to through this work in
order to give it a better look.

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TABLE OF CONTENTS
Title page
Declaration - - - - - - - - ii
Approval page - - - - - - - - - iii
Dedication - - - - - - - - - iv
Acknowledgements - - - - - - - - v
Abstract - - - - - - - - - vi
CHAPTER ONE
1.0 Introduction- - - - - - - - -
1.1 Objective of the Study- - - - - - - -
CHAPTER TWO
2.0 Literature Review- - - - - - -
2.1 Gluten- - - - - - - - -
2.1.1 The Role of Gluten in Baked product- - - - -
2.2 Celiac Disease- - - - - - - - -
2.2.1 Symptoms of CD- - - - - - - - -
2.2.2 Diagnosis of CD- - - - - - - - -
2.3 Gluten Free Food - - - - - - - -
2.2.1 Major examples of Gluten Free foods- - - - -
2.4 ProblemsAssociated with Production- - - - -
2.4.1 Weak structure- - - - - - - - -
2.4.2 MoldingProblem-- - - - - - - -
2.4.3 Inferior sensory and nutritional Quality- - - - -
2.4.4 The production costs - - - - - - - -
2.4.5 Low nutrition in certain ingredient -- - - - -
2.5 Solutions to the problemsrelated with the production of GFbaked
foods- - - - - - - - -
2.5.1 Weak Structure- - - - - - - - -
2.5.2 Low nutrition in certain ingredient -- - - - -
2.5.3 Production Costs Problem- - - - - - -
2.5.4 Low nutrition in certain ingredient -- - - - -

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2.5.1 Extrusion-cooking processes- - - - - - -
2.5.2 Temperature control- - - - - - - -
2.5.4 Bio-processing fermentation- - - - - - -
CHAPTER THREE
3.0 Conclusion and Recommendation- - - - - --
3.1 Conclusion - - - - - - - -
3.2 Recommendation- - - - - - - -
References- - - - - - - - -

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CHAPTER ONE
1.0 INTRODUCTION
The production of traditional bakery products involves four steps of which
ingredient mixing, dough kneading, fermentation and baking are involved.
Gluten plays an important role in all of these procedures (Ziobro et al., 2016).
Gluten is a general name given to the protein class that gives elastic properties
to wheat. It is also a property that allows bread and other risen bakery
products to be processed (Arendt & Moore, 2006). The gluten conveys
structurethat allows flour to rise and hold its shape when baked. Gluten exists
not only in wheat but to a lesser degree, in relatives of wheat such as rye,
spelt, triticale, barley and kamut.
However, for people born with certain health conditions, the gluten in wheat
can cause problems (Armstrong et al., 2012; Aronsson et al., 2015; Furlán &
Chen, 2017). There are three main forms that human reacts towards gluten
intake. These are allergic (wheat allergy), autoimmune (celiac disease,
dermatitis herpetiformis and gluten ataxia) and immune-mediated (gluten
sensitivity) (Therdthai et al., 2016).
About 2% of the global population suffers from Celiac disease and the gluten
intolerance is extremely restrictive. The only treatment is applying a healthy
food and avoiding any food which contains gluten. An increasing demand of
gluten-free (GF) products is caused by a growing number of diagnosed celiac
diseases and a consumption trend to eliminate allergenic proteins from diet.
Attempts are thus, made to adopt methods that could produce cereal based
gluten-free products with technological properties comparable to their gluten
containing counterparts and minimum compromises with quality (Alvarez et
al., 2010). GF bakery products are often less desirable in terms of their
appearance, taste, aroma and texture. The simplest way to improve the
structure of GF products is by adding other functional ingredients and
additives(e.g. starches, protein, gum, hydrocolloids, emulsifiers, dietary fibre)
to the wheat flour substitutes (e.g. rice, maize, sorghum, buckwheat,
amaranth, quinoa, corn, chickpea) as reported by numerous authors (Arendt
& Moore, 2006; Różyło et al., 2015; Rocha et al., 2015a; Akesowan, 2016).
1.1 OBJECTIVE OF THE STUDY
To highlight the challenges associated with the production of gluten free
baked products.

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CHAPTER TWO
2.0 LITERATURE REVIEW
2.1 Gluten
The name glu-ten is derived from this glue-like property of wet dough. Gluten
is a mixture of two proteins present in cereal grains, especially wheat, which
is responsible for the elastic texture of dough. (Arendt and Moore, 2006).
When flour is mixed with water, the gluten proteins form a sticky network
that has a glue-like consistency. This glue-like property makes the dough
elastic, and gives bakery product the ability to rise when baked. It also
providesachewy, satisfying texture. Gluten is one of the most commonly used
proteins in the food industry. Its characteristic properties make it an
important ingredient for the production of high quality dough, hence its
popularity in the food (baking) industry (Zilic, 2013).
2.1.1 The Role of Gluten in Baked product
Wheat flour's unique properties in yeast‐leavened baked goods are due to
gluten. it is composed of 2 main protein fractions, gliadins, which contribute
essentially to the viscosity of the dough and glutenins, responsible for dough
elasticity (Steffolani, 2014). Gluten becomes apparent when wheat flour is
hydrated and subjected to the energy of mixing, even by hand. It is a
viscoelastic mass that has the ability to form thin gas‐retaining films that trap
gases, allowing dough to expand to become a softer, lighter and palatable food
after baking (Costantini et al., 2014).
In baked goods, gluten is a key functionalcomponent. It provides extensibility,
mixing tolerance and gas-holding ability to the dough, all of which influence
product structure and volume. Gluten contains the protein fractions glutenin
and gliadin. The former is a rough, rubbery mass when fully hydrated, while
gliadin producesaviscous, fluid mass on hydration. Gluten, therefore, exhibits
cohesive, elastic and viscous properties that combine the extremes of the two
components. The gluten matrix is a major determinant of the properties of
dough (extensibility, resistance to stretch, mixing tolerance, gas holding
ability), enclosing the starch granules and fibre fragments. A significant
challenge to eliminating gluten from a traditional bread dough system is the
change from plastic dough to a liquid batter. Resulting products are very
different in appearance, texture, and eating quality (Steffolani et al., 2014).

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2.2 Celiac Disease
Celiac Disease is a disease in which the small intestine is hypersensitive to
gluten, leading to difficulty in digesting food. When people with celiac disease
eat gluten, their body mounts an immune response that attacks the small
intestine. These attacks lead to damage on the villi, small fingerlike
projections that line the small intestine, that promote nutrient absorption.
When the villi get damaged, nutrients cannot be absorbed properly into the
body (Newnham, 2017).
More so, in the cases of celiac disease, the immune system mistakes
substances found inside gluten as a threat to the body and attack them. This
damages the surface of the small bowel (intestines), disrupting the body’s
ability to absorb nutrients from food. Exactly what causes the immune system
to act in this way is still not entirely clear, although a combination of a
person's genetic make-up and the environment appear to play a part (Leffler
et al., 2015).
Epidemiological studies estimate a worldwide prevalence of CD of
approximately 1:100 individuals, with a considerable proportion of patients
remaining undiagnosed and untreated (Flande et al., 2011). The ingestion of
gluten in genetically predisposed individuals carrying alleles can arouse a T-
cell mediated immune reaction against tissue transglutaminase, an enzyme of
the extracellular matrix, leading to mucosal damage and eventually to
intestinal villous atrophy (Clerici et al., 2009). Gliadins are supposed to be the
active fractions of gluten. They contain the immunogenic peptides (especially
the 33mer) and are able to exert a direct cytotoxic effect on the cell (Shepherd
et al., 2014). The clinical manifestations of CD are heterogeneous and range
from the so-called “classical” syndrome with diarrhea, weight loss and
malnutrition, to selective malabsorption of micronutrients (iron, vitamin B12,
and calcium), (Elli et al., 2015).
2.2.2 Symptoms of CD
The symptoms usually involve the digestive system and cause abdominal
discomfort, bloating, nausea and loose bowel movements. However, there is
a wide spectrum of symptoms that may occur. The intestine becomes
inflamed. It may also lose its ability to absorb nutrients from the diet, leading
to other associated illnesses. Treatment of celiac disease is following a strict
gluten free diet(Leffler et al., 2013).

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2.2.2 Diagnosis of CD
The diagnosis of CD is classically based on a combination of findings from a
patient’s clinical history, serologic testing and gastroscopy by means of
duodenalbiopsies. Even in the absence of clinical symptoms, the screening for
CD should be considered among the first-degree relatives of celiac patients,
patients with type-I diabetes mellitus and patients with Down’s syndrome,
given the high prevalence of CD in these and other at risk groups (Volta et al.,
2014).
2.3 Gluten Free Food
Gluten free food is food which does not contain composite of storage proteins
termed prolamins and glutelins stored together with starch in the endosperm
of various cereal grains (Moreira et al., 2012). GFDs have several short
comings such as adversely altered intestinal flora and an elevated risk of
micronutrient deficiencies in patients with CD. Some of the risks and
drawbacks that go with gluten free diet include limited variety of healthy food
choices, increased intake of necessary nutrients such as carbohydrates,
protein, fiber, folate, iron, vitamin B-3, calcium and increased food cost
(Miñarro et al., 2012).
Korus (2015)foundoutthat on average, gluten-free products are about 160%
more expensive than regular products. Other problems include decreased
number and variety of beneficial bacterial in the gut, which may make the
immune system less effective, increased intake of wheat replacement that,
have higher glycemic indexes and lower fiber and protein levels than wheat
,decrease fiber intake, which can cause constipation and other digestive issues
increased intake of fat, sodium, and calories. Fat and sugars are often used as
replacement in gluten-free products.
2.2.1 Major examples ofGluten Free foods
The following grains and other starch-containing foods are naturally gluten-
free food: Rice, Cassava, Corn (maize), Soy, Potato, Tapioca, Beans, Sorghum,
Fruits, Vegetables, Meat, and poultry, Fish and seafood, Dairy, Beans, gumes,
and nuts, Millet Buckwheat, groats (also known as kasha) Arrowroot
Amaranth and Chia Gluten-free oats Nut flours Many items that usually
contain gluten have gluten-free alternatives that are widely available in most
grocery stores, and make living gluten-free much easier.

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2.4 Problems AssociatedwithProduction
Working with non-wheat flours has a number of challenges which include
weak structure, molding problem, inferior sensory and nutritional quality,
high production costs and low nutrition in certain ingredient,
2.4.1 Weak structure
When wheat flour is removed or reduced in a formulation, so are the two
proteins, glutenin and gliadin, responsible for forming gluten also go missing.
When glutenin and gliadin are mixed with water, they connect and cross-
connect to form elastic strands of gluten, which then capture and retain
leavening gasses and provide structure to baked foods. Gluten also aids in
binding water, a key factor in freshness (What’s, 2016).
2.4.2 Molding Problem
With gluten-free bread, there is no single gluten-free flour that is a direct
substitute for wheat flour. So, often you use twice as many ingredients, with a
mix of different flours and starches, to get a similar texture and flavor. Low-
gluten and gluten-free systems tend to resemble liquid batters and, therefore,
can present challenges with production equipment,” “In terms of shelf life,
many gluten-free formulations contain more bound water than their wheat-
based counterpart, which can create a molding problem. Traditional gluten-
free flours and starches have very little inherent nutritional value, which is
why gluten-free systems are primes for fortification (Witczak, 2016).
2.4.3 Inferior sensory and nutritional Quality
In the past, gluten-free baked products have been described as being less
cohesive and elastic than wheat dough’s, difficult to handle and have poor gas
holding retention. The products these breads and dough’s create have been
portrayed as having inferior sensory and nutritional quality compared to
wheat products, as it usually presentscrumbly texture, low volume, poor crust
color, taste and aroma, short shelf-life, high glycemic index, and low protein
and high fat content (Giuberti et al., 2015; Arendt et al., 2009; Minarro et al.,
2012).
2.4.4 The production costs
The production costs for manufacturers have also proven to be problematic,
as bakery equipment needs to be guaranteed gluten free, ingredients tend to

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be costly, and distribution can be difficult due to the higher rate of staling of
the products.
2.4.5 Low nutrition in certain ingredient
Despite the advances been made in this area practically by focusing on
reviewed and new ingredientsas processing methods, maize, potato, rice flour
and starches are currently utilized in gluten free flours. These are used as base
flours due to their bland flavor and neutral effects on baked products. These
flours and starches usually tend to be low in nutrition and have very minimal
structure-building potential (Norah et al., 2015).
2.5 Solutions to the problems relatedwith the productionof GF baked
foods
In other to address the problems related to the production of GF baked food,
listed above. The following solutions are necessary in solving them.
2.5.1 Weak Structure
Specific contribution of gluten to texture relates to the strength of the dough,
the size and uniformity of the air cells within the dough, and the presence of a
heterogeneous matrix within the dough. Weaker dough yields larger and less
uniformly sized air cells. Weaker dough also exhibits greater heterogeneity
and yields a longer, chewy texture. Stronger dough has smaller and more
uniformly sized air cells and exhibits a less heterogeneous appearance. The
strength of the gluten replacement system is critical to mimic of the targeted
bread product. The physical space that the gluten occupies within the dough
in a whole wheat bread also requires compensating adjustments. An effective
replacement method must ensure that the volume and weight contributed by
the gluten protein are replaced with a gluten-free alternative ingredient.
For poor structure (inability to retain CO2, appearance of a dense crumb
grain) and the lack of nutritional content, some ingredients such as flour oil
and olive oil has been used to aid the process. These two oils have been used
in chestnut dough as a possible means to improve the rheological properties
of chestnut flour-based doughs. Adding these oils to the flour decreased the
water absorption of the resulting doughs, while decreasing the stability of the
dough. These oils decreased the apparent viscosity and storage modulus of
the chestnut doughs (Rafiq et al., 2017). You have not given any strong
solution to weak structure formation.

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2.5.2 Low nutrition in certain ingredient
According to Catassi (2012), one can choose from a number of alternative
ingredients. However through a method of “trial and error” one has to
establish the most suitable recipe. What follows is a list of ingredients one can
choose from.
 Rice flours, brown and white, to replace wheat flour
 Buckwheat flour and teff flour
 Almond flour
 Fibres (apple, psyllium, pea)
 Rice proteins, for water binding,
 Rice starch, instant or cook-up, for elasticity and adhesion,
 Tapioca starch, instant or cook-up, for elasticity and adhesion,
 Non-hydrogenated vegetable oils, for tenderizing,
 Xanthan gum or CMC (carboxymethylcellulose), for film forming and
water binding,
 Guar gum, for film forming and water binding,
 Sugar, e.g., sucrose, for water binding
 Milk powder
 Egg powder
Sorghum or brown rice flour, presents itself as potential viable flour in the
development of gluten-free products. It has been reported to contain good
nutritiveproperties such as vitamins E and B, iron, folate, essential fatty acids,
and dietary fiber (nutritional components which gluten-free products are
usually lacking (Blanco et al., 2011).
Blanco and others (2011) investigated the effects of 4 additives (acetic acid,
lactic acid, citric acid, and monosodium phosphate) in a rice flour and
hydroxypropyl methylcellulose) HPMC-based bread formulation. It was found
that the use of monosodium phosphate increased loaf volume significantly; it
was also noted that the inclusion of this additive resulted in the largest cell
area compared to the control. These positive effects may be a consequence of
hydrogen bondingduringthe proofingstage between HPMC and monosodium
phosphate, preventing the CO2 from escaping, thus resulting in larger loaf
volumes.
Many researchers have been carried out to enhance the nutrition of gluten
free product. Krupa-kozak and others (2011) used two types of calcium
supplements (calcium caseinate [CAS] and calcium Citrate [CIT]) and
investigated their addition on the baking characteristics of a gluten-free

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formulation. At 2% addition, CIT showed the most positive effect on bread
characteristics. Its presence increased the specific volume from 2.29 cm3/g
(control sample) to 3.34cm3/g. Inclusion of CIT was also found to increase
bake loss; the authors suggested this was due to larger cell volume found in
the crumb structure which would accelerate the loss of moisture.
Gomez and others (2013) investigated the effects of mixing speed, time;
mixing attachment and proofing time on gluten free dough and batter (that
contained 80% and 110% water). The authors found that higher water
additions led to batter-like consistencies, and required mixing regimes similar
to that of cakes, that is, lower mixing speed but longer mixing time, and using
a whip wire mixing attachment to incorporate more air and bubbles into the
batter. It was also observed that longer mixing times had a positive effect on
the amountof CO2 produced. Two reasons for this were proposed; 1st, longer
mixing times permits greater oxygenation which allows yeast to reproduce
under its preferred aerobic conditions. Second, greater mixing times allow
amylase to produce maltose, which is the reserved food source for yeast after
sucrosehas been consumed duringproofing. A shorter mixing time would not
allow for these 2 occurrences, therefore, fermentation would cease in the first
15 min of proofing leading to a reduction in CO2 production and a reduced
final loaf volume. Longer proofing time (90 min) was required for the sample
containing 110% water, compared to the sample which contained 80%
moisture (50 min). The authors suggest that a fluid batter can retain more air
and expand more easily during proofing. Beyond the optimal proofing time,
the structure developed becomes too weak to support itself and collapses
(Gomez and others 2013).
2.5.3 Production Costs Problem
Demirkesen and others (2011) compared infrared-microwave baking to
conventional baking as a possible cost-saving method. The authors proposed
that using microwave ovens offered advantages such as energy efficiency,
faster heating, space savingand food which retained better nutritional quality.
Findings showed how microwave power and infrared power were 2 of the
prominent factors effecting bake loss, firmness, and specific volume. When
these 2 factors were at the maximum levels, a higher level of bake loss was
attained, resulting in a drier crumb with a firmer texture. Infrared power
particularly affected loaf specific volume. It increased the temperature of the

17. 17
crust more quickly than the crumb, thus reducing the ability of the crumb to
develop, resultingin a reduced volume. Theoptimized baking conditions were
calculated to be 40% infrared, 30% microwave power and a baking time of 9
min.
2.5.4 Low nutrition in certain ingredient
There for, for partially baked products to retain its quality, a hydrocolloid
such as xanthan gum is required. A possible solution to this problem has been
described in “bio processing approaches.” It was also noted that the effects of
staling which occur duringstorage of the partial baked breadscan be reversed
in the 2nd phase of baking via melting of the amylopectin.
It has been documented that Sourdough (an age-old bioprocessing method)
has positive benefits in bakery products. It involves a cost effective and
ecologically friendly method. The production of sourdough is described as a
mixture of flour, water, and other ingredients (for example, sugar, salt),
fermented with lactic acid Bacteria (LAB) and yeasts (Zannini et al., 2012).
The gluten-replacing ingredient must help with water management in a
similar manner. Water must be controlled in order to postpone the rate of
staling and to preventmould. Theshelf life of a gluten-free producttendsto be
equal to or less than that of a typical wheat-based product, dependingon what
the product is and how it is stored. The strategic application of sugars helps to
bind water and manage such changes during storage (Becker, 2012).
The flavours and textures of gluten-free ingredients generally do not result in
a product that would be considered acceptable when compared with a
refined-flour product. However, the likelihood of success in mimicking the
flavours and textures of whole wheat, whole grain, or brown breads is far
greater. Currently, many gluten-free products available on the market are of
low quality, exhibiting poor mouth feel and flavour. Such problems are rarely
encountered during the manufacture of gluten-free biscuits, as the
development of a gluten network in biscuit and cookie dough is generally
minimal and undesirable; the texture of baked biscuits is primarily
attributable to starch gelatinisation and super-cooled sugar rather than a
protein/starch structure (Campo, 2016).

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Plate 1: summary of some approaches used to improve the structure, texture,
acceptability, nutritive value, and shelf life of GFB.
Source: (korus et al., 2015)

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2.5 Other novel technologies approach for improving gluten free
baked product
Technology such as, extrusion-cooking process (Clerici et al., 2009), high-
pressureprocessing(Villons et al., 2011)and microwave baking (Therdthai et
al., 2016)have also been investigated to improve the texture and quality of GF
dough and bread.
2.5.1 Extrusion-cooking processes
Pasta products are normally produced using cold single screw extrusion
process. The twin screw extruder can be successfully applied in the
production of brown rice GF pasta at elevated feed moisture and screw speed.
At the optimized condition, the cooking loss is lesser this indicates good
quality products (Rafiq, 2017). Starch hydration properties can be greatly
affected by extrusion parameters as when starch granules are heated in the
presence of water, the hydrogen bonds that hold the structure will weaken,
thus allowing the granules to absorb water and swell (Mohammadi et al.,
2015). As starch is the major component of the rice kernel, changes in
physicochemical properties during extrusion processes will dictate the
properties of rice pasta (Farrell et al., 2010).
2.5.2 Temperature control
This is an important parameter for GF bread and cake ((Witczak et al., 2016).
For GF bread, some studies used infrared–microwave heating technology to
improve moisture distribution inside the food and to remove the surface
moisture faster, hence increasing the pore number while decreasing the pore
size (Demirkesen et al., 2013a). The use of sourdough lyophilised at 20 °C led
to the production of larger volumes in GF bread; however, the structure of
crumb and shelf life was better when lyophilised temperature was at 40 °C.
The higher preparing temperature at 60 °C caused the least changes in bread
volume.
2.5.4 Bioprocessing fermentation
Bioprocessing fermentation has been applied to eliminate or reduce the
gluten protein in wheat flour. According to Demirkesen et al., (2013b), the
nine amino acid core sequences of some restricted but unique epitopes were
identified in wheat, barley and rye which stimulated a response in individuals
with coeliac disease. To eliminate the gluten protein, different lactic acid
bacteria, yeasts and enzymes have been used in sourdough fermentation.

20. 20
CHAPTER THREE
3.0 Conclusionand Recommendation
3.1 Conclusion
The major challenges to these findings on dietary compliance and the quality
of gluten free baked foods were addressed to be, weak structure, molding
problem, the production costs, low nutrition in certain ingredient. Some novel
techniques used for improving GF products such as Extrusion-cooking
processes, Temperature control, Bio processing fermentation were addressed
as well as their solutions.
3.3 Recommendation
Based on the research, the following recommendations are made:
i. Research should be focused on the discovery and application of
more innovative gluten substitutes and the cultivation and
commercialization of the celiac-safe wheat
ii. Extensive research on the improvement of nutritional quality of
gluten-free product is needed
iii. Focus on additives of good sensory evaluation should be lean
upon to safe consumers of non gluten product.

21. 21
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