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Citric Acid

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How To Define Citric Acid Chemical Name?

Citric acid is a strong organic compound with the chemical formula HOC(CH₂CO₂H)₂. It is always known as a colorless weak type of organic acid found. It is generally present naturally in citrus fruits. In this biochemistry, it is known as the intermediate cause involved in the citric acid cycle, which occurs or is found in the metabolism of all aerobic organisms. 


Citric acid is available in natural form in several fruits and vegetables. Still, most notably, you can taste their presence in citrus fruits like lemons and lime that contain a high volume of citric acid. It might take you by surprise, but Citric acid can take up to 8% of the fruit's total dry weight.

 

Discovery of Citric Acid

The first isolation of Citric acid took place in 1784 by the chemist named Carl Wilhelm Scheele, who experimented by crystallizing it from lemon juice. Citric acid is present in two forms in nature. One is the water free form, which is called anhydrous, and the other one is monohydrate. However, in both forms, the chemical name, and the Citric acid structure remains the same. 

 

On the other hand, Citric acid's isolation on an industrial scale first took place in 1890 in Italy. As the citrus fruit company used hydrated lime, which is Calcium hydroxide, to precipitate Calcium citrate in the juice. The Calcium Citrate was being isolated and got converted back to acid, which then gets diluted by sulfuric acid. 

 

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Citric Acid Chemical Formula

Citric acid is said to be a tribasic acid. As a result, if you want to prepare acidic salts of Citric acid, you can do it by carefully balancing pH before the compound's crystallization starts to occur. One of the examples of acidic salts derived from this acid is Sodium citrate. 

 

The Citric acid chemical formula is C6H8O7. In its naturally occurring form, the Citric acid crystals have white colour, which you can also find on the top of sour candies. 


Preparation of Citric Acid

You can get Citric acid from the market as it is a weak acid. You do not need to have a special order to buy it from a local chemical store. If you want to prepare it by yourself, you need to follow the given steps.

 

Step 1:- First, you need to have lemons, and we mean lots of lemons. You need 450 ml of lemon juice to extract a good amount of crystallized Citric acid. Test the lemon juice by using a pH strip. The result should be around a 2 or 3 pH scale. 

 

Step 2:- Add a little bit of eyedrop, which contains 10% strength Sodium hydroxide, and test the solution again. Now take the coffee filter and pour down the solution into another glass. Also, at this stage, check for any solid particles in the solution that you poured into a new flask.

 

Step 3:- Now put 28 grams of Calcium Chloride into 70 ml of distilled water and combine both the solutions in one glass and heat it. 

 

Step 4:- Again, filter out the solution using a coffee filter to get calcium citrate out of it. Now, as the Calcium citrate is taken out, mix it with heavily diluted sulfuric acid, and then stir it. Filter out the solution with water, and store the citric acid in a beaker. 

 

Step 5:- Heat the solution on medium heat so the water gets evaporated from the beaker. Finally, filter out the Citric acid and let it cool down in a bowl. 

 

Properties of Citric Acid

We have already discussed the structure of Citric Acid. Now, let us move to citric acid's properties. The citric acid common name is citrate, and the systematic IUPAC name of Citric acid is 2-Hydroxypropane-1,2,3-tricarboxylic acid. 

 

The Citric acid density is 1.66 g/cm³. The density is one of the important properties of any chemical compound as it defines how much of it can mix in any particular substance. The molecular weight of Citric acid, which is present in the monohydrate form, is 210.14 g/mol. 

 

Uses of Citric Acids in Daily Life 

  • There are several ways in which Citric Acid benefits humankind. Below are some of the major uses.

  • First, in beverages, Citric acid provides tartness and enhances the fruits and berries flavours. Also, with its addition, the antimicrobial preservatives get a boost, and it provides adjustments in pH to give uniform acidity to the soft drinks. 

  • In frozen fruits, Citric acid makes pH go lower to make oxidative enzymes inactive. 

  • In pharmaceuticals, this acid works as an effervescent combined with bicarbonates to provide rapid dissolution of active ingredients.


Importance of Chemistry

Chemistry is really important and efficient for the research and study of living organisms because it helps students and scientists to understand the life processes of every living thing on earth at the molecular level. At any molecular level, every process of life takes place due to the involvement of various minor or major chemical reactions.


How to Study Chemistry?

Thus, the students need to learn their chapters well and understand all the chemistry concepts by practicing with a maximum number of past years’ question papers and sample question papers available on the Vedantu website. This will help them to understand the time management skill and learn the marking schemes that carry maximum marks and plan which question needs what type of answers. Break down larger portions into smaller effective points and write them down in a separate notebook so it will help you in revising before the exams. 


Make note of the important questions that keep repeating in the recent past year question papers and give more weightage to those questions and prepare a little extra because it might repeat in the current year also. If you have any doubts about the equations and chemical formulations that are taught during the classes then try to spend some extra time in the lab and get to understand all the concepts by trying out the experiments and practicing them really well. This will definitely help you write your formulas and equations really well.

FAQs on Citric Acid

1. What are the Popular Substitutes for Citric Acid?

There are four amazing substitutes found for citric acid.

  • Lemon juice is found in many households and is a great substitute for citric acid.

  • Tartaric acid comes in only as a second choice if you don't have lemon juice handy.

  • White Distilled Vinegar and 

  • Ascorbic Acid / Vitamin C.

2. Is Citric Acid a Natural Preservative?

Citric acid is very effective and serves the food and beverage industry as a natural preservative to keep the food fresh for a longer period. The naturally occurring acid found in citrus fruits such as lemons and limes functions as a preservative in its organic state. Its high acidity makes it difficult for mold, bacteria, or any negatively impacting substance to survive inside them.

3. What is the Shelf Life of Citric Acid?

Store citric acid in its original container in a cool, dry place. Generally, from the date of manufacturing, it has a shelf life of three years once it is opened and will stay stable and fresh for at least five years if it is unopened. However, Citric acid starts to lose its potency over time if it is not stored properly. The super good news is that you can actually preserve citric acid's potency by storing it in an airtight container.

4. Is Citric Acid and Vinegar the Same in Nature?

Vinegar is almost similar to citric acid and gives a similar sour flavour. To use this as a substitute, start by using triple the amount of vinegar for citric acid in any recipe you prepare, and add more to the taste. The only specific reason for this issue is that vinegar is known as a much weaker acid than citric acid, so you need more to get the same amount of effect a vinegar solution will give. On the other hand, Citric acid isn't stronger in chemical nature than vinegar because the acetic acid present in the vinegar is a lot more aggressive and corrosive when it comes in contact with particular surfaces. But, there are also many types of mineral deposits present that citric acid can actually better deal with.

5. What do You use Citric Acid for?

Citric acid is most often effectively used as a natural preservative or to add an acidic or sour taste to food and baked products as well. It can also be used as an effective emulsifying agent. Because of its acidic and sour-tasting nature, citric acid is predominantly used as a flavoring and preserving agent in some particular food preparation, especially in the production of soft drinks and candies. It is also used to stabilize or preserve certain medicines and utilized as a disinfectant. Citric acid is a compound that is originally derived from lemon juice. Manufactured citric acid is one of the most common types of food additives in the world. It's used to boost the acidity level, enhance particular flavors, and preserve specific ingredients in the food industry. In the case of, Sodas, juices, powdered beverages, candies, frozen foods, and some dairy products, they will often contain some percentage of manufactured citric acid in them.

6. Where can you find Citric Acid in nature?

Citric acid is a natural preservative, and it is used in the food industry to add a sour taste to food and soft drinks. However, in all these food items, Citric acid is added artificially and is not present naturally. 

 

When it comes to finding out Citric acid's natural occurrence, we need to look at fruits and veggies such as lemons, limes, oranges, grapefruits, pomelos, and tangerines. On the other hand, Citric acid is present in almost every fruit but in lesser quantities. These fruits are Pineapple, Strawberries, Cherries, and Tomatoes. Eating these fruits will help in better metabolism and keep bloating and constipation away. 

7. What are the risks of taking Citric Acid?

Companies that produce Citric acid with chemical reactions help to manufacture it under the Food and Drug Administration (FDA). At present, there is no study suggesting that consuming artificially manufactured Citric acid has any negative impact on health and the body when consumed in large amounts for more extended periods. 

 

However, there are cases of people falling sick, and people have an allergic reaction to the additive. One report showcases joint pain with swelling and stiffness and muscular and stomach pain in 4 people. Also, these individuals were feeling shortness of breath. All 4 of them consumed artificially manufactured Citric acid, which is present in their food items. 

 

The same problem cannot be seen in consuming Citric acid from fruits and veggies such as lemons and limes. Lastly, scientists conclude that mold, used to prepare Citric acid, might cause pain.