Which of the following is used as chemical preservatives? A. Citric acid B. Nitric acid C. Oxalic acid D. All of the above
Hint: Food preservation practices include food processing practices that inhibit the growth of microorganisms such as yeasts (although some methods work by introducing harmless bacteria or fungi to the food) and slow the oxidation of fats that causes rancidity.
Complete answer: Chemical food preservatives are substances that, under certain conditions, either slow the growth of microorganisms without necessarily killing them or prevent quality deterioration during manufacturing and distribution. The former category includes some naturally occurring food constituents that when added to foods, slow or prevent the growth of microorganisms. Sugar is used for this purpose in jams, jellies, and marmalades, as well as in candying fruit. This category also includes the use of vinegar and salt in pickling, as well as the use of alcohol in brandying. To prevent the growth of microorganisms, some chemicals that are not normally found in foods are added. The latter group includes some naturally occurring food constituents, such as ascorbic acid (vitamin C), which is added to frozen peaches to prevent browning, as well as a long list of chemical compounds that are not found in foods and are classified as antioxidants, bleaching agents, acidulants, neutralizers, stabilizers, firming agents, and humectants. Citric acid and phosphoric acid are flavoring and preservation agents added to carbonated beverages and fruit drinks. Nitric acid and oxalic acid are highly acidic and can harm the digestive system.
Thus, the answer is option A: Citric Acid
Note: Sodium benzoate and other benzoates are common chemical preservatives. Most countries allow the use of benzoates in certain products in prescribed amounts (usually not exceeding 0.1 percent), though some require a declaration of its use on the food container label.