Sweetener then appeared
One evening in June 1878, the Russian-born American chemist Constantine Fahlberg (1850-1910) was busy working in a chemical laboratory Experiment and forgot to eat dinner. It was late at night. He hurriedly returned home. He didn't have time to wash his hands, so he picked up the bread and ate it. He felt an indescribable sweetness. It just occurred to him that it might be some kind of sweet bread, and he rinsed his mouth with water and wiped his hands with a napkin that was sweeter than the bread when it touched his lips. When he raised the wine glass that his fingers had touched and drank again, the wine glass was as sweet as when it touched the napkin. He was surprised to realize that his fingers had brought from the laboratory a substance sweeter than sucrose. He gave up his dinner and ran back to the laboratory. In his excitement, he tasted the contents of the beakers and evaporating dishes placed on the laboratory table. Fortunately these substances did not poison him, but he found a compound that tasted sweeter than sucrose. He continued his research for several months, determining the chemical composition and properties of the compound. In 1879, Falbao named this compound saccharine, which comes from the Greek word sakcharon (sucrose). We call it saccharin. It is a white crystal that dissolves in hot water. It is 400 to 500 times sweeter than sucrose and has a slightly bitter aftertaste. .
These circumstances of the discovery of saccharin are based on Falbao's own report published in the American magazine "American Analyst" (Amer. Analyst, 2, 211, 249 (1886)) published in 1886.
Today’s report sounds a bit ridiculous, because students who have conducted experiments in the chemistry laboratory know that chemicals in the chemistry laboratory are not allowed to be imported for tasting. But more than 100 years ago, this was not surprising to chemists. It is precisely because these ancestors engaged in research regardless of their own risks that they left us precious wealth.
Falbao received the Gibbs Award of the Chicago Chapter of the American Chemical Society [in memory of the American chemist and former president of the Academy of Sciences Oliver Wolcott Gibbs (1822-1908)] , honorary degrees from several American universities and gold medals from the British Chemical Industry Association.
Falber received a doctorate in philosophy from the University of Leipzig in Germany in 1873. He successively conducted research in Germany, the United States and the United Kingdom, and entered Johns Hopkins in the United States in 1878. ) University to do postdoctoral research with chemistry professor Ira Remsen (1846-1927). They jointly studied the oxidation of o-toluenesulfonamide (CH3C6H4SO2NH2) and discovered o-sulfonylinimide, saccharin. Saccharin is generally its sodium salt, called saccharin sodium.
Farbau initially made a few grams of the product in a flask in a chemical experiment and planned to build a factory in the United States. However, the high cost of production and high taxes on raw materials forced him to build a factory in Germany. . His route for making saccharin is to first extract toluene from coal tar, react with chlorosulfonic acid (ClSO2H) at 0~5°C to generate ortho- and para-toluene chlorosulfonyl (ClO2SC6H4CH3), and then react with ammonia (NH3) , generating ortho- and para-toluenesulfonamide (SO2NH2C6H4CH3). After separation, ortho-toluenesulfonamide is obtained, and then oxidized and dehydrated to form saccharin Bernard E. Schaar. Chance favors prepared mind, part III, Artificial sweeteners． Chemistry, 1968, 41(3). :
This production process was later improved by some people, using different raw materials, one of which uses anthranilic acid (C6H4NH2CO2H) as raw material. Our country uses this as raw material for production.
Saccharin cannot be digested and absorbed in the human body. It is just a flavoring for diabetic patients to replace sugar.
At the end of the 19th century and the beginning of the 20th century, during the tenure of Theodore Roosevelt (1858-1919), the 26th President of the United States, Harvey W. Wiley, an official in charge of food and medicine I am very opposed to the consumption of saccharin.
He believed that it was a coal tar product that had absolutely no edible value and was extremely harmful to human health. But President Theodore Roosevelt accepted the doctor's advice and did not suffer any physical harm after consuming saccharin. He said: "Whoever said that saccharin is harmful to health is a fool." The president also organized some scientists to set up a review committee and hired Ray Johnson served as the chairman of this committee, which conducted review tests on saccharin and proved that saccharin is safe.
In 1979, someone in the United States found that feeding saccharin to rats caused cancer, and the U.S. Food and Drug Administration announced a temporary ban on the consumption of saccharin. But Congress bowed to public pressure and passed a shelved extension. Saccharin is still used today.
In addition to saccharin, there are also some chemically synthesized sweeteners, such as sodium cyclohexane sulfamate (C6H11NHSO3Na). This discovery was as serendipitous as the discovery of saccharin. In 1937, Michael Sveda, a chemistry student at the University of Illinois, studied the properties of a compound similar to sulfa drugs (19) under the guidance of chemistry professor L.F. Audrieth. One day in November 1937, while working in the chemistry laboratory, Sverda placed the lit cigarette on the experimental table. When he picked up the cigarette again, he felt a sweet taste, so he tasted every compound on the experimental table. It was discovered that a compound in a crystallization dish had a sweet taste, which was sodium cyclohexane sulfamate.
This narrative seems ridiculous, not only tasting the chemicals in the laboratory, but also smoking in the laboratory. This is prohibited today.
Odriz and Sverda successively sold the patent to two American chemical companies for production, but were rejected by both companies because its sweetness was only 30 times that of sucrose. By 1942, the American DuPont Company tested its performance and found that this compound was more stable than saccharin at high temperatures, did not have residual bitterness like saccharin, and had a sweetness closer to sucrose. After approval by the Food and Drug Administration, the calcium salt from which it was made was produced and marketed under the brand name sucaryl.
Sodium cyclohexane sulfamate was banned in 1969 because it was found to cause bladder cancer in mice. Later, a series of test results were negative. But sodium cyclohexane sulfamate remains banned in the United States. This may be the fear most people have about coal tar products as edible substances.
There is also a sweetener discovered by German chemist Joseph Berlinerblau. He was studying organic synthesis at the University of Berlin in Germany. He studies the chemical reactions of chlorine cyanide (ClCN) with various aromatic amines. While studying the reaction between cyanide chloride and p-ethoxyaniline (C2H5OC6H4NH2), when treating the intermediate product with water, he accidentally isolated a new compound - p-ethoxyphenylurea (C2H5OC6H4NHCONH2), which has a sweet taste. , published an article reporting the discovery of this new compound in 1884, and obtained a patent a few years later.
P-ethoxyphenylurea is a shiny needle-shaped crystal or powder, which is about 200 times sweeter than sucrose and does not have the bitter taste left behind by saccharin. Feeding tests on animals have given mixed results, with some deeming it safe for normal consumption and others proving it to be toxic. The main opinion is that as a food or drug it does more good than harm. It was put on the market around 1893. The trade name is dulcin, which originally means sweet. We call it dulcin or sweetener.
But today its use is still banned in many countries, saying that it is a carcinogenic compound.
Chemists also found a natural sweetener - stevia, which is a perennial herb native to Brazil, Paraguay and Argentina in South America. my country has successfully introduced and tested its leaves. It contains a sweet substance (steviol glycoside) that is 300 times sweeter than sucrose. It is a good natural sweetener and is used in the food industry or for diabetic patients.