issue+about+citric+acid





The most of people who we interview, they don’t know what is citric acid. But their had heard about citric acid and in their opinion, citric acid is as flavoured sour in some food and drink. Ok. Want to know more about citric acid? Let’s check it out!

History The discovery of citric acid has been credited to the 8th century Islamic alchemist Jabir Ibn Hayyan(Geber).Medieval scholars in Europe were aware of the acidic nature of lemon and lime juices, such knowledge is recorded in the 13th century encyclopedia Speculum Maius (//The Great Mirror//), compiled by Vincent of Beauvais. Citric acid was first isolated in 1784 by the Swedish chemist Carl Wilhelm Scheele, who crystallized it from lemon juice. Industrial-scale citric acid production began in 1890 based on the Italian citrus fruit ind ustry.

In 1893, C. Wehmer discovered that //Penicillium// mold could produce citric acid from sugar. However, microbial production of citric acid did not become industrially important until World War I disrupted Italian citrus exports. In 1917, the American food chemist James Currie discovered that certain strains of the mold //Aspergillus niger// could be efficient citric acid producers, and Pfizer began industrial-level production using this technique two years later, followed by Citrique Belge in 1929.

In this production technique, which is still the major industrial route to citric acid used today, cultures of //Aspergillus niger// are fed on a sucrose or glucose-containing medium to produce citric acid. The source of sugar is corn steep liquor, molasses, hydrolyzed corn starch or other inexpensive sugary solutions. After the mould is filtered out of the resulting solution, citric acid is isolated by precipitating it with lime (calcium hydroxide) to yield calcium citrate salt, from which citric acid is regenerated by treatment withsulfuric acid. In view of the fact that the isolation of citric acid from fruits is very expensive, it is commercially produced from sugar with the help of bacteria and yeasts. And the yeasts that used to produced it is //Aspergillus Niger//. This process more efficient and cheaper.

Definition Citric acid is a weak organic acid. It is a natural preservative and is also used to add an acidic, or sour, taste to foods and soft drinks. In biochemistry, it is important as an intermediate in the citric acid cycle and therefore occurs in the metabolism of virtually all living things. It can also be used as an environmentally benign cleaning agent. Citric acid exists in greater than trace amounts in a variety of fruits and vegetables, most notably citrus fruits. Lemons and limes have particularly high concentrations of the acid; it can constitute as much as 8% of the dry weight of these fruits (about 47 g/L in the juices). The concentrations of citric acid in citrus fruits range from 0.005 mol/L for oranges and grapefruits to 0.30 mol/L in lemons and limes. Within species these values vary depending on the cultivar and the circumstances in which the fruit was grown. This is the structure of citric acid



Where we can be found it? Citric acid occurs naturally in many foods and is responsible for lending an acidic or sour flavor. And we can get it in some fruit, food and drink, for example:

**Citrus Fruit** As suggested by the name, citrus fruits contain a high amount of citric acid, with a general guide that sweeter fruits contain less acid. Limes, lemons, oranges, tangerines and grapefruits are some acidic citrus fruits. **Berries** Red currants, raspberries and blackberries have a high amount of citric acid. **Juices and Sodas** Citrus juices naturally contain a high amount of citric acid; the acid is sometimes added to sodas as a flavoring. Always check the nutritional information to find out if a juice or soda contains citric acid. **Tomato** Tomatoes are one of the vegetables with the highest amount of citric acid. This acid gives tomatoes their signature taste. **Cheese** Many cheeses contain citric acid to help speed the cheese-making process. Check the labels before buying supermarket cheese and shop at a cheese monger if you have a citric acid intolerance. These are samples of product that contain citric acid:

1. Rejoice shampoo( to remove useless metals )



2 . frutang ( as an accidulant)



3. Nutrijell ( to add sour taste )



4. Calpico( to add sour taste)



5. Pocari Sweat ( to add sour taste )



6. Marjan Syrup( to add sour taste )



7. Marimas ( as an accidulant )



8. mountea( as an accidulant )



9. sprite ( to add sour taste )



Other information As a food additive, citric acid is used as a flavouring and preservative in food and beverages, especially soft drinks. Within the European Union it is denoted by E number (E330). Citrate salts of various metals are used to deliver those minerals in a biologically available form in manydietary supplements. The buffering properties of citrates are used to control pH in household cleaners andpharmaceuticals. In the United States the purity requirements for citric acid as a food additive are defined by theFood Chemical Codex, which is published by the United States Pharmacopeia(USP). And you can get more information in other our page.  What an expert in organic chemistry say? This is our interview with our organic chemistry teacher in Bogor High School of Chemical Analyst. He is Mr. Rusman, M.Si. Let’s listen it! media type="file" key="MOV03B.3gp" width="300" height="300"