Citric Acid and Salt | Explore Common Applications

Citric acid and salt were discovered in the 18^th century. With the technological development in changing times, they have many applications, which means a lot to our human beings. In this article, we will mainly explore their uses and effects in agricultural fertilizers, food processing, metal protection, and human health care.

1.They are used to produce agricultural fertilizers.

Citric acid and salt are used in agricultural fertilizers because of the following effects.

Firstly, fertilizer containing citric acid and salt can increase the acidity of soil. They can dissolve minerals in the soil and release hydrogen ions, therefore, they can lower the pH value of the soil. This acidic environment helps plants absorb nutrients and provides a more suitable growth environment for plants, esp. for acidic plants like blueberries.

Secondly, they can improve the absorption capacity of plant roots by lowering the pH value of the soil. Meanwhile, they can also increase the concentration of active ions in plants, promoting their growth and development.

Thirdly, they can promote the transformation of nutrients and form complexes with iron and calcium ions in the soil. In this way, it is easier for plants to absorb and utilize them. Therefore, fertilizers containing citric acid and salt can promote the growth and development of plants, and thus increase crop yields.

What’s more, they can improve soil structure, enhance soil water retention capacity, and improve crop drought tolerance and disease resistance.

2.They are used to ensure food safety and hygiene.

Citric acid and salt are preferred in food addictive because they can ensure food safety and hygiene. They are effective because they can promote chelation, buffering, antioxidant, and anti-corrosion effects in food.

Firstly, citric acid and salt have strong chelating ability. They can bind with metal ions in food to prevent adverse effects on the quality and taste of food caused by metal ions. For example, in the processing of meat products, they can bind with iron ions and prevent iron ions from oxidizing and causing discoloration of the meat.

Secondly, they also have a buffering effect. There will be changes in food acidity and alkalinity during processing, storage, and transportation. This will cause quality deterioration to certain degrees. Citric acid and salt can stabilize the acidity and alkalinity of food and prevent quality deterioration. In baked goods, they can help regulate the acidity and alkalinity of the dough and make the bread softer and more delicious.

Thirdly, they have antioxidant features. They can delay the oxidation process of food, maintain the color, taste, and nutritional value of food. They can prevent the oxidation and destruction of nutrients such as vitamin C in fruit juice and beverages.

Finally, they also have an anti-corrosion effect to inhibit the growth of microorganisms in processed foods. Therefore, the shelf life of canned food and pickled products can be extended.

3.They can prevent kidney and urinary system stones.

Citric acid and salt can alkalize urine, lower uric acid, and prevent kidney and urinary stones. What is the principle behind this? Citric acid and salt belong to a type of base and they can increase the pH value of urine and enhance the solubility of uric acid in urine.

The same amount of urine can dissolve more uric acid, and the more uric acid is excreted with urine, the lower the uric acid in the body. Besides, as the solubility of uric acid in urine increases, it is less likely for uric acid crystals to precipitate.

Therefore, citric acid and salt are strong inhibitors of stones in the human body. They can inhibit the formation of calcium oxalate stones by alkalizing urine, reduce the formation of uric acid crystals, and increase the excretion of citrate in urine.

4.They can be used in metal protection.

Citric acid and salt are an adsorption film-type organic corrosion inhibitor. They can coordinate with iron ions and dissolve iron oxides. Using a citric acid and salt solution instead of a hydrochloric acid solution to clean steel can avoid the corrosion damage caused by chloride ions to austenitic steel. Therefore, for structurally complex boilers with austenitic steel applications, citric acid and salt solutions are usually used as the cleaning solution.

The application of citric acid and salt as additives in metal protective film treatment solutions is still limited, and it has gradually attracted the attention of scholars in recent years.

The experimental results show that the addition of organic additives is beneficial for improving the hardness, thickness, and corrosion resistance of alumina films. This is because the stable macromolecular complexes formed by it block the pores of the membrane layer. It hinders the entry of corrosive ions into the pores and therefore improves the corrosion resistance of the membrane.

Conclusion

This article lists several applications of citric acid and salt. In fertilizers, they can promote plants’ growth and improve soil quality. In food, they can stabilize the acidity and alkalinity of food. Besides, they can also prevent stones from the human body and protect metal from corrosion.