ANALYSIS OF POTASSIUM BROMATE IN BREAD SAMPLED FROM ENUGU METROPOLIS
Table Of Contents
<p></p><p> <b>TABLE OF
CONTENT</b></p>
<p><b><i>Title page
i</i></b></p>
<p><b><i>Approval page ii</i></b></p>
<p><b><i>Dedication
iii</i></b></p>
<p><b><i>Acknowledgement
iv</i></b></p>
<p><b><i>Abstract
v</i></b></p>
<p><b><i>List of tables vi</i></b></p>
<p><b><i>Table content vii</i></b></p>
<p><b> </b></p>
<p><b>
Chapter ONE
:</b></p>
<p>1.0<b> </b>Introduction 1<b></b></p>
<p>1.1
Potassium bromate 3</p>
<p>1.2
Justification 6</p>
<p>1.3 Aims and
Objective 7</p>
<p><b>
Chapter TWO
:</b></p>
<p>2.0
Literature Review 8<b></b></p>
<p>2.1
Chemistry and Production of potassium bromated 9</p>
<p>2.2 Uses of
potassium bromated in bread 10</p>
<p>2.3 Toxicity
and carcinogenicity of Potassium bromate (KBrO3) 11</p>
<p>2.4 Brief
history of bread 15</p>
<p>2.5
functional ingredients in bread production 17</p>
<p>2.5.1 Flour 18</p>
<p>2.5.2 Liquid
19</p>
<p>2.5.3 Yeast 20</p>
<p>2.5.4 Fats
and Shortenings 21</p>
<p>2.5.5 Bread
Improvers 22</p>
<p>2.5.6 Salt 23</p>
<p>2.6
Previously reported work on toxicity and carcinogenicity of</p>
<p>Potassium
bromate 24</p>
<p><b>
Chapter THREE
:</b></p>
<p>3.0
Materials and Method 33<b></b></p>
<p>3.1
Materials and apparatus 33</p>
<p>3.1.2
Reagents 34</p>
<p>3.2 Methods 35</p>
<p>3.2.1 Sample
collection and preparation 35</p>
<p>3.2.2
Reagent preparation 35</p>
<p>3.3
Quantitative analysis of potassium bromate in bread 39</p>
<p>3.4 Qualitative
analysis of potassium bromate in bread 41</p>
<p><b>
Chapter FOUR
:</b></p>
<p>4.0 Result
and Discussion 42<b></b></p>
<p>4.1
Qualitative and quantitative determination of potassium</p>
<p>Bromate 46</p>
<p>4.2
Colorimetric reading for standard curve 47</p>
<p>4.2
Conclusion and Recommendation 49</p>
<p><b>REFERENCES </b> 5<b></b></p>
<br><p></p>
Project Abstract
<p></p><p> <b>ABSTRACT</b></p>
<p>This
work was carried out in the eastern part of Nigeria to investigate the presence
of residual potassium bromate in bread. 25 different brands of bread were
sampled from Enugu metropolis. The samples were analyzed using a previously
reported method (David 1976). A freshly prepared 1% potassium iodide in 0.1N
hydrochloric acid was used to develop the colour. The result revealed that all
25 bread samples contained residual potassium bromate. Sample A, C, R, S, T, W
and X did not show any visible colour change when treated with potassium
iodide. Sample C and X; 26mg/kg has the lowest concentration of residual
potassium bromate. Sample B; 146mg/kg has the highest quantity. Sample N and Y;
108mg/kg also recorded quantities above 100mg/kg. Potassium bromate usually
used as a bread improver is a carcinogen. All bread samples are therefore
considered unsafe for human consumption.</p>
<br><p></p>
Project Overview
<p></p><p><b>1.0
</b><b>INTRODUCTION</b><br></p>
<p>Bread is an important source of food prepared by cooking dough of
flour and water, and possibly more ingredients. Dough is usually baked but in
some cuisines, breads are steamed, fried or baked on an unoiled skillet. It may
be leavened or unleavened salt, fat and leavening agents such as yeast and
baking soda are common ingredients. Though bread usually contains several
ingredients that would help improve the quality of the bread. Some of the basic
identified ingredients apart from flour include: table salt, sugars, flavours
and at least a floor improver such as potassium bromate (Vicki, 1997). Other
ingredients may also include milk, egg, spice, fruit (such as raisins),
vegetables (such as onions), nuts (such as walnuts) or seeds (such as
poppy-seeds). The ever-growing popularity of bread may be connected with its
convenience, high acceptability, high energy content and low level of blood
cholesterol associated with its consumption (Gaman and Sherington, 1981). Water
and flour are the major component in a bread recipe. They affect the bread
texture and crumb properties.</p>
<p> The major challenge in
both flour milling industries and bakeries is the baking quality of flour,
which is determined by the capacity of the dough prepared from it to retain
gas. As a result of wide variation in the composition of flour, various
treatments and supplements conditioning agents (flour/bread improver) are added
for strength during mixing, extensibility for molding and also to increase loaf
volume and texture.</p>
<p>Over the years, several improvers have been used but studies have
shown some to be deleterious to health, thereby necessitating their ban. The
use of potassium bromate has been a common choice among flour miller and bakers
throughout the world because it is cheap and probably the most efficient
oxidizing agent. It acts as a slow oxidizing agent throughout the fermentation
proofing and baking process affecting the structure and the rheological
properties of the dough. As a result, many bakeries use potassium bromate as an
additive to assist in the raising process and to produce a texture in the
finished product that is appealing to the public (Sherington, 1981).</p>
<p> </p>
<p><b>1.2 POTASSIUM BROMATE </b></p>
<p>Potassium bromate is a flour improver that acts as a maturing
agent. It acts principally in the late dough stage giving strength to the dough
during the late proofing and early baking (Kurokawo <i>et al., </i>1990). Potassium bromate takes the form of white crystals
or powder. Potassium bromate has been used as a dough conditional for the past
60 years. According to USDA, it improves dough processing properties, internal
crumb quality and low volume in concentration from a few to 75ppm, the highest
concentration permitted by law. The mechanism by which bromate acts in dough is
complex and not well understood (Destefanis, 1992).</p>
<p> In early 1990’s, the
World Health Organization (WHO) discovered that potassium bromate if consumed
has the capacity to cause such diseases as cancer, kidney failure and several
other related diseases. The adverse effect of potassium bromate on health and
its health effects are divided into two categories. The first category deals
with effects related to non-cancer effect. This includes its effect on the
nutritional quality of bread. It degrades vitamin A2, B1,
B2 and niacin which are the main vitamins available in bread (IARC,
1999).</p>
<p>Studies (IARC, 1999) have shown significant difference in essential
fatty acid content of flour treated with bromate or in bread made from flour
containing bromate.</p>
<p> In humans, potassium
bromate can cause cough and sore throat when inhaled (Atkins, 1993). Abdominal
pain, diarrhea, nausea, vomiting, kidney, are some of the other non-cancer
health problems associated with ingestion of potassium bromate (Atkins, 1993).
In the secondary category, numerous studies have revealed the potential of
potassium bromate to cause cancer in experimental animals and in humans (CSPI,
1999); Watson, 2000). Using bromate as bread improver has been banned (Ekop <i>et al., </i>2008). Also, in Nigeria, the bromate use in bread
making was banned in 1993 (Obot <i>et al., </i>2008).
However, some bread makers have continued to include potassium bromate in their
bread.</p>
<p> Furthermore, a
preliminary survey revealed that some other materials employed in bread making
(e.g. water) and the environments where these bakeries are located are not free
from contamination by heavy metals such as lead.</p>
<p><b>1.3 JUSTIFICATION</b></p>
<p> Bread is one of the
oldest, stable and most reliable source of food. Its consumption is very high
in the eastern part of Nigeria where most of the bread makers has resorted to
using potassium bromate as a maturing agent for flour and as a dough
conditioner in order to improve the quality of the dough and allowing higher rising.
Potassium bromate has been considered a category 2B (possibly carcinogenic to
humans) carcinogenic by the International Agency for Research on cancer (IARC).
In addition, it has negative effect on the nutritional quality of bread. It
degrades vitamins A2, B1, B2, E and niacin in
bread (IARC 1999).</p>
<p> This study confirms the
presence of residual amount of potassium bromate in different brands of bread
samples in Enugu metropolis.</p>
<p><b> </b></p>
<p><b>1.4 AIMS AND OBJECTIVES</b></p>
<p>To determine the presence of potassium bromate
in different brands of bread sampled</p>
from Enugu metropolis.
<br><p></p>