Approaching Chemistry: Acetic Acid vs Citric Acid

We can summarize the taste on our tongue as sour, sweet, bitter, spicy, and salty. Acid is a very important taste sensation. This flavor is often contained in foods with acidic substances, such as vinegar or lemon. Today we will learn about acetic acid vs citric acid. What are their characteristics? What is their purpose? What are the differences between them? Let's explore together.

Acetic acid vs citric acid: What are they?

1.Acetic acid

It is a common organic acid and the main component of vinegar. The concentration of commercially available industrial acetic acid usually exceeds 98% and cannot be consumed directly. It can solidify below 16 ℃, and its aqueous solution has strong corrosiveness to metals. The steam generated after heating is irritating to the eyes and nose, so it should be stored carefully.

Acetic acid is a product of brewing. Currently, many countries' food safety regulations require that food vinegar must be prepared through bacterial fermentation.

Aerobic fermentation and anaerobic fermentation are two ways of bacterial fermentation. The former has a short fermentation cycle and uses foods such as potatoes or rice that can produce alcohol. It achieved success for the first time in Germany. The latter produces acetic acid from compounds containing only one carbon, such as methanol. This method has lower costs and enormous potential.

2.Citric acid

As we mentioned at the beginning, there are many sources of sourness, among which citric acid is currently the most widely used sour food additive. It naturally exists in citrus fruits and is not an essential nutrient for the human body. The widely used citric acid currently is artificially synthesized.

How to synthesize citric acid? In summary, give Aspergillus niger sugar and mix it with ingredients such as potassium phosphate. After one to two weeks of fermentation, citric acid is born. This method has a history of over a century.

Acetic acid vs citric acid: What are their applications?

1.Acetic acid

A study released in Europe in 2005 also found that consuming vinegar together with high GI foods could lower postprandial blood sugar levels and insulin response. At the same time, it was found that the intake of acetic acid was positively correlated with blood glucose levels and insulin response. These findings were confirmed again in 2017 by a study from the International Diabetes Federation.

In addition to stabilizing blood sugar, vinegar can also help you eat less salt. Food without taste is difficult to swallow. However, some people like to eat dishes with strong flavors, and even after adding a lot of salt, they still feel that the taste is not enough. Adding vinegar is a good solution. Because vinegar can enhance the salty taste, adding more vinegar when stir-frying can reduce salt intake.

Although acetic acid has the above benefits, it must not be consumed directly or applied in large quantities to the skin. Because it can burn the esophagus, the skin, and corrode tooth enamel. If you want to drink or apply it to the skin, please dilute with water in advance to reduce the concentration.

2.Citric acid

If you want to consume natural citric acid, you should eat more citrus fruits, especially lemons and lime. However, their content is not enough to be used for treating diseases such as kidney stones. This pharmacological effect still needs to be applied to products such as potassium citrate.

In traditional medicine, citric acid is considered to have great benefits for the lungs. It can also promote the healthy secretion and function of bile. Moreover, due to the stimulating nature of sour foods, foods such as lemon have a refreshing effect and can also promote digestion.

Nowadays, in the food industry, citric acid has three main functions: making the taste richer, protecting color, and inhibiting bacteria. Firstly, it can impart a fruity flavor to beverages and make the acidity richer. Secondly, it can act as a color retention agent as it can inhibit the browning reaction of fruits and vegetables. Finally, it is an effective preservative because its weak acidity can inhibit bacteria.

Conclusion

How to enhance the flavor of food is an enduring topic. Acetic acid vs citric acid are important sources of sourness. Compared to the other, the former has a higher acidity. Moderate intake of acidic foods can stimulate our appetite and have certain benefits for the lungs and digestion. But if you have gastrointestinal problems, you should still consume it with caution as it may corrode your mucous membranes. Overall, please choose whether to consume acidic foods based on personal circumstances.