How Do Different Sugar Substitutes Affect The Rising Of Bread
One of the oldest types of food that is still very prominent in today’s society all around the world is bread. Bread has been prepared since tens of thousands of years ago and the methods of making it has been stable, with few modifications. It can be prepared in many ways, such as being steamed, fried, or more commonly, baked. The simple way to prepare bread is through a series of steps. These consist of mixing the needed ingredients such as flour, yeast, water, sugar, and salt. Once all ingredients have been mixed, the dough is then kneaded. The flour in the bread is a starch, which consists of long strands of sugar molecules that help with fermentation that takes place. Once the process of fermentation takes place, the bread is then ready to be baked and enjoyed.
Besides yeast and flour, sugar is one of the most important ingredients when making bread. Yeast requires sugar to go through the process of fermentation, that helps the bread rise prior to being baked and while being baked. Glucose and maltose are the main types of sugar that help bread go through fermentation. Because bread is so simple and so universal, the concept of making bread is often used in science experiments as it shows the different chemical properties of each simple ingredient and how they affect the outcome of the bread.
As well as bread, sugar has also been used in different types of foods and recipes since ancient times. Sugar is a type of carbohydrate that the human body needs to create energy through processes like cellular respiration, which is also a process that is found in fermentation. In the human body, simple sugars such as glucose and fructose are the most abundant, although there are also different sugars such as maltose and dextrose. Through chemical synthesis, sugar substitutes also play a large role in some diets, mainly catered towards diabetics, people who are obese, and people with hypoglycemia so that they could obtain the necessary energy needed from sugar without the health consequences of normal sugar. Some prominent examples of sugar substitutes include aspartame, saccharin, and sucralose. These types of sugars can replace regular sugars in different types of recipes for even the most basic types of foods.
There have been numerous experiments conducted on testing the health risks of different types of sugar substitutes to make sure that they are actually safe enough to be used on humans. In an experiment conducted by Myra Karstadt, aspartame, the top artificial sweetener (since 2011) used in the US (2011), was tested on rats to see if the long-term exposure had any sort of carcinogenic effect on the animals. Up until 2005, sucralose, under the brand name of Splenda, was the leading sugar substitute and took up more than 50% of the market for sugar substitutes. Sucralose is used with acesulfame potassium which had to go through numerous tests with the FDA to be approved for everyday use in human diets. The tests for approval for acesulfame potassium to be available to the public began in 1988 and became approved to be used in soft drinks in 1998.
The numerous tests taken on rats and mice came out negative for any carcinogenic effects, opening the door for approval to be used by the general public. Soon, the sugar substitute became available for direct addition to foods and for human consumption. In June 1986, another evaluation for potential of carcinogenic effects got put into place by the FDA. In the final test for approval in 2003, the National Toxicology Program (NTP), tested both aspartame and acesulfame on genetically modified rats to see if the carcinogenic test would come back negative. As the results came back negative, the FDA finally approved the use of acesulfame potassium in 2003 to be used in not just soft drinks, but as a general sweetener to be used freely (2011).
In comparison to nucleic acids and proteins, sugars are the most difficult types of biopolymers to study because of their complexity and how there are so many possibilities as to what type of sugar they may form. If mannose and glucose were to bind together, they have the ability to form a disaccharide in about 80 different ways (Flitsch, 2003). Determining the glycome, or the sugar code of what two common sugars may form, can be done through microarray techniques. These techniques also show how the sugars may interact with different types of proteins. In an experiment studied by Flitsch, an important sugar-protein interaction can be found in the study of human blood group antigens. These antigens, A, B, and O, have one major difference, which is found in the oligosaccharide sequence. Here, located on the surface of red blood cells, the carbohydrate sequence is what ultimately determines the differences between the antigens (2003).
These antigens are then recognized by sugar-binding proteins which ultimately cause blood clotting (blood agglutination). The proteins themselves contain sugars that are linked to immune responses, lectins that link cell-surface sugars, antibodies, and different enzymes such as glycosidases and glycosyltransferases (2003). Although these oligosaccharides pertain to simple saccharides and disaccharides, these effects are not as prominent with the use of sugar substitutes, since they are synthetically made and do not provide as much energy as regular sugars such as glucose. This sugar microarray technology can be useful in the future when determining what type of sugars bind best with proteins or how sugar patterns may change from one form to another (2003).
In an experiment studied by Ana Domingos, the reward value of nutrients and the analysis of its effects was shown through a series of tests that included exposing mice to 2 different types of water. One sipper of water was filled with regular, dispensed water which triggered optogenetic simulation of DA neurons (dopaminergic neurons) while the other was filled with sugar substitutes mixed into the water. The mice preferred the optogenetic stimulation over sucralose, but preferred sucrose overall (2011). Leptin, a hormone that regulates energy balance through the inhibition of hunger. This hormone is found in adipose tissue which sends signals through a negative feedback loop and ultimately maintains control of homeostasis. This hormone can modulate or moderate reward in the nervous system.
In the experiment, the leptin reduced the reward value of sucralose, which is why the mice and rats preferred the optogenetic stimulation over the sucralose (2011). The effects of the reward values ultimately altered the motivation from the mice and rats. This reward system works similarly with humans, as the reward levels from sugar substitutes do not have effects as strong as regular sugars, meaning that diabetics are able to take sucralose when their blood sugar levels are low according to this experiment. By decreasing reward values, leptin helps diabetics when they take sugar supplements to help reduce the craving for sugar (2011).
As mentioned previously, cellular respiration is one major event that takes place during the process of making bread. Cellular respiration happens when fermentation takes place as well. It is a multistep process that breaks down organic molecules such as glucose to energy that can then be used. Through cellular respiration, adenosine diphosphate (ADP) is converted into adenosine triphosphate (ATP) which works as a fuel for activities that take place within the cells of plants, bacteria, animals, and protozoa (Scholer A. & Hatton, M. 2018). This process is the basis for the majority of recognized life forms. Cellular respiration, although often taught in an introductory biology class, is also brought up in cellular biology, biochemistry, and physiology. The basic concepts of humans/animals consuming oxygen, releasing carbon dioxide, and ultimately going through cellular respiration are taught, going down to the details of how it occurs in the mitochondria of cells.
If there is no oxygen available, then anaerobic respiration takes place, which either stops or slows down cellular respiration. Through the cellular respiration process, the splitting of sugars, also called glycolysis, produces 2 ATP’s, further than that, the sugars are broken down to CO2 and H2O. Glycolysis (splitting of sugar), transition reaction (pyruvic acid moved to mitochondria), Krebs cycle (citric acid cycle), and electron transport chain (electrons from hydrogen carried by NADH and passed down the electron transport chain) these are the four basic steps to cellular respiration (2018). In the process of making bread, the yeast goes through cellular respiration. While making bread, the yeast goes through aerobic respiration which creates water and carbon dioxide that help the bread rise. Once there is the depletion of oxygen, anaerobic respiration takes place and carries out to the end of baking and the process of bread making (2018).
The chemical component of making bread is not the only thing that makes bread special, it is also the wheat genome that has been studied recently. This genome, in an experiment studied by Peter Langridge, proves to be complex and large. In fact, it is about 6 times the size of the human genome because it is made up of hexaploids that are 6 sets of chromosomes that come from 3 different genomes (2014). In 2011, approximately 681 million tons of wheat was produced, and agricultural companies decided to improve the wheat strains through selective breeding. This was due to the fact that without selective breeding, the global demand for wheat would not be met without any sort of genetic modification. To meet the global demand, wheat production must increase by at least 60% by the year 2050 (2014). This is not a simple task, because it is hard to differentiate between the three different genomes and the sequence assembly has proven to be difficult to determine. Through clone libraries and shotgun sequencing, the wheat genome has been able to increase at a steady rate. This is further expected to meet the expected global demands by 2050 if the method of genome sequencing continues and factors such as climate change do not slow down the production of wheat (2014)..
In the process of making bread, one of the main ingredients, sugar, is used to help the yeast go through the process of fermentation. As stated earlier, the chemical process of bread making is not the only thing that makes bread such a prominent area to study in science. The growing wheat genome and the selective breeding of wheat helps with the production of bread for the world to enjoy. This ties into how cellular respiration and fermentation works and how sugars and different sugar substitutes affect processes like fermentation and cellular respiration. Cellular respiration is a process with many steps that breaks down glucose or other sugars into energy. Glycolysis, a part in cellular respiration, is about how the splitting of sugars occur, which is what happens when yeast fermentation takes place. This splitting of sugars is also found in sugar substitutes like aspartame or acesulfame potassium. Sugars are the most complex biopolymers and each monosaccharide has their own, multiple attachment sites.
These complex processes is one of the main reasons why sugar substitutes are so widely studied so scientists and corporations like the FDA can approve such substitutes for regular use. Experiments like the regulation of leptin shows how animals are able to regulate different types of sugar intakes and sugar substitutes in certain types of foods. For example, sucralose is suppressed by leptin which further helps with understanding how sugars are broken down. Through these numerous experiments with the different types of sugar substitutes that are synthetically made help give us a better understanding how they can be used in day to day life. Although bread has been made for thousands of years and is considered to be one of the most simple foods, the chemistry behind the making of bread is still continued to be studied because of the many components. It is not just a matter of making some dough and putting it in the oven, it is a whole chemical process that must occur before it turns into the bread that has brought up thousands of generations.