Hey, I did a report on this and got an A! Here is the info:
1. Identify two acids used as food additives
Two acids used as food additives are:
Phosphoric acid with formula H3PO4
Acetic acid with formula CH3COOH
2. Explain the use of these acids as food additives in their chemical properties
Phosphoric acid is used as a food additive because it is of low toxicity, it is incompatible with strong caustics and most metals, it is soluble in alcohol and hot water, the liquid can solidify at temperatures below 21 C, and it can form three series of salts: primary phosphates, dibasic phosphates and tribasic phosphates. It is also deliquescent, hygroscopic and a chelating agent.
Acetic acid, the main component of vinegar, is used in pickling vegetables, chutneys and sauces. Pure acetic acid is moderately toxic by ingestion and inhalation, but dilute material is approved by FDA for food use. Acetic acid is a general preservative that inhibits many species of bacteria, yeasts and to a lesser extent moulds. It is also a product of the lactic-acid fermentation, and its preservative action even at identical pH levels is greater than that of lactic acid. Acetic acid can also stabilise the acidity of food and at the brewery, acetic acid may be added to the malt slurry to compensate for variations in the water supply to produce a beer of consistent quality. Acetic acid is used because it is hygroscopic and it is infinitely soluble in ethyl alcohol and water. As acetic acid inhibits bacterial growth and absorbs water as well, when food is pickled, spoilage does not occur as quickly.
