Bulkiness is given to the gluten developed and to the bread than Ascorbic acid. Also, potassium bromate effect gives a smoother and more beautiful look to the bread. This means that more loaves can be obtained using potassium bromate than Ascorbic acid, (Guideline, 1998). Guideline further report that it was formerly used in Japan in fish paste production and may be used in production of cheese and beer, further important application potassium bromate include the following
Flour Improver/ Flour Maturing Agent/Flour Enhancer
Flour is not a perfect substance but technological advancement has made it possible for it to be milled and eaten in the same day.
Most flour in their natural state does not meet up with desired baking quality, hence, this deficient properties has to be corrected by various treatments and supplements. Practically, all flour is treated with additives today, either in the mill or bakery to correct certain baking quality or colour.
In bread baking, potassium bromate is called an “Improver” as it has the capability of improving the quality of flour because it remains inert until yeast fermentation lowers the pH of the dough sufficiently to activate it. As a result of this late reaction in dough it causes increased loaf volume, improved loaf symmetry, crumb and texture characteristics (American Society of Bakery Engineers, 1997).
These qualities have endeared bakers to potassium bromate, hence the resistance to change. Further uses of bromate include making rolls, buns etc.
(Aggraval, et al., 2000), reported that bromate salts of potassium and sodium are used as neutralizer in cold wave hair permanent kits. As a neutralizer, bromate was an active ingredient of waving lotion (Aggraval, et al., 2000). A solute ion of potassium bromate according to them was prepared from 2% potassium bromate with 10% sodium bromate.
However, this prompted another ugly use of bromate in several cases of poisoning, primarily in children under the age of 4years. One further report was the case of suicidal act by some hair dressers in Japan as bromate was used as a suicidal agent.
Potassium bromate conditions dough because it contains functional ingredient that strengthens disulphide bonds in dough which makes bread have a “super kick” that prevents it from falling thereby improve processing and product quality in bread making.
Aside from all these uses stated above, bromate residues still remain high in baked food. (Cogswell,1997), reported on the annual conference in Kansa city held by the American Society of Bakery Engineers (ASBE) that low bromate residue can be achieved by the incorporation of certain ingredients like;
vAscorbic Acid: When 40-100ppm of ascorbic acid is added to the dough.
vFerrous Sulphate: When ferrous sulphate is added for enrichment rather than reduced iron.
vBleached flour: When bleached flour is used rather than unbleached flour.
vLower pH: When the pH of dough is at 5.2 rather than 5.7.
vLonger fermentation time: When potassium bromate is added to roll dough and the fermentation time is five hours instead of two or three hours and when potassium bromate is added to bread dough and fermentation time is at least three hours.
v Increased bake temperature: When bread is baked at 221 C (420 F) rather than at 193 C(380 F)
v Increased bake time: When bread is baked for longer than 22minutes and when rolls are bake for twelve minutes rather than eight minutes.
She concluded that quality control is critical when using potassium bromate. How much potassium is used in a formulation will change for many reasons but one thing that is obvious is a change in flour quality. If the flour quality changes and has a lower tolerance for the current formulation and machinability, then processing changes are accommodated. These changes may be summarized as fermentation time change and the amount of potassium bromate used, as well as changes in the amount of other oxidizers or dough conditioners.
HEALTH HAZARDS OF POTASSIUM BROMATE
The health hazards of potassium bromate cannot be over emphasized. Generally, it has been reported the health hazards of potassium bromate is due to prolonged period of usage (Attang, 2003). As reported before, prolonged administration of bromate on rats and mice was known to cause cancer of the kidney, thyroid etc.
This carcinogenesis was induced by the active radicals produced by bromate on interaction with the tissue cells (Nakal, et al., 2002). It is these radicals that eventually lead to the DNA peroxidation and cell death. Carcinogenesis involves a segmented accumulation of genetic and epigenetic lesions which the initiating agent maybe chemical, viral, radiation related (Schein and Umemura, 2002). In the baking industry, the dangerous effects of bromate were observed by its ability to decompose flour vitamins A, B1, B2, Niacin and E which are useful to the body (Ajayi, et al 2003).
Vitamin A is very essential for vision, growth, and development of skeletal and soft tissue especially in children.
Vitamin B1, B2 and Niacin
Are essential or active parts of co-enzymes that are involved in metabolic reactions in the body that release energy Adenosine Triphosphate (ATP).
Is an antioxidant that prevents the release of peroxides and free radicals formed from fats in the body? Peroxides destroy the cell membranes of the body causing aging. The vitamins fortify flour to combat vitamin deficiencies.
At this juncture, it is expedient to point out that human beings are not used for experiment to ascertain the carcinogenicity of potassium bromate, instead laboratory animals like rat, mice etc are used, then results from the use of these laboratory animals and its effects are projected to human beings.
Other hazardous effects of bromate were noticed in the results obtained for the mutagenecity of potassium bromate in Salmonella typhimuriun stain TA 100 using Ames test and for chromosomal aberrations in cultured Chinese hamster fibroblast cells (Ishidate, M., 1984). On a follow up effect was the positive results obtained also in an in vivo study of the acute cytogenetic effect of potassium bromate on rat’s bone marrow cells. (Fujie, 1998)
. Other mutagenic effects of potassium bromate were found in the mouse micronucleus test, evidence of DNA damage in rats given potassium bromate. Finally, the reproductive effects of potassium bromate were also evaluated in a study in which rats and mice were fed with flour treated with 15mg of potassium bromate per kg over five and eight generations respectively. However, no effects on reproductive performance or survival were observed in either species, but other tissues like the spleen, eye, liver, skin and kidney were much affected.
The above findings led to the ban and removal of bromate from the list of improvers or food additives classified as GRAS meaning “Generally Regarded As Safe” by the Joint Committee of FAO/WHO on food additives in 1992. Bromate have been banned in numerous countries including the United Kingdom in 1990, Canada 1994, California 1991, (http:/www.espinet.org.). In Nigeria, bromate was banned by Food and Drug Administration (FDA) a parastatal under Federal Ministry of Health 1993 now known as National Agency for Food and Drug Administration and Control (NAFDAC).