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Citric Acid

Citric Acid

A weak organic acid, citric acid is a natural preservative which is found abundantly in citrus fruits. Its molecular formula is C6H8O7.
Rajib Singha
The fact that citric acid belongs to a family of weak acids explains the reason why is it safe to ingest and touch. Fruits such as lemons and limes are known to bear tremendous amounts of citric acid in them, and this is why these fruits are bitter. The acid is also present in high quantities in fruits like oranges and tangerines; however, not as much as in more bitter citrus fruits. Raspberries and blackberries also contain this acid. Commercially, citric acid powder is utilized in food preparation and canning, pharmaceuticals, and water softening.

Uses of Citric Acid

Given its naturally sour taste, one of the widely known uses of citric acid is in the form of a food additive. When it comes to flavoring and preservatives in foods and beverages, this acid just fits the bill. And how can we forget soft drinks. The label on any can of soda declares this acid as one of the ingredients. The acid is denoted by E number E330. In sweet food products, the acid serves to control the acidity of other ingredients in the food.

Then comes the process of water softening, which also employs citric acid. Chelation is defined as "the process of forming a ring by forming one or more hydrogen bonds". The acid has the property to chelate metals and that is the reason why it is a useful agent in soaps and laundry detergents. What the acid does is that by causing chelation of the metals in water, it helps produce more foam.

In medical science, citric acid, apart from being a vitamin supplement, is used in rehabilitation programs for alcoholics. In case you had not known this fact, this acid is also an essential part of an open-heart surgery. The acid in pumped into the body with the purpose of calming down heart contractions in order to ease the procedure. It may also be used to prevent blood clotting.

Some More Uses
  • One of the compounds of citric acid is applied in the manufacturing of blue prints. This compound is known as ferric ammonium citrate.
  • This acid also finds its applications in photography, in the form of one of its compounds. It is known as sodium citrate. This, along with other chemicals, is used to cause light-responsive paper into photographs.
  • This acid is used as an active agent in many cleaning products meant for kitchen and bathroom.
  • Several effervescent formulae contain this acid as one of their vital ingredients.
  • When added to ice cream, the acid helps to keep the fat globules separated.
  • Most brands of inexpensive wines make use of citric acid.
  • The manufacture of mozzarella cheese and production of anti-viral tissues has the acid as one of the active ingredients.
Citric Acid Allergy

Most people have this problem called citric acid intolerance/allergy. As the name suggests, it is a condition which refers to unpleasant symptoms which people suffer from in response to foods or other products containing this acid. Symptoms include skin rash, skin redness, hives, swollen eyes, dark circles, and swelling of limbs, mouth, and tongue. Also, this allergy may trigger runny nose, difficulty breathing, sweating, coughs, sneezes, nasal congestion, and teary eyes. Apart from these symptoms, one may also come across ear infections, stomach distress, including nausea, vomiting, diarrhea, constipation, etc. The same acid is also known to cause psychological symptoms in people. Common ones include moodiness, hyperactivity, aggression, and anxiety.

And to conclude, local supermarkets during normal canning season, local pharmacy, local health food store and online retailers are where you can avail this multipurpose acid.