The Effect of Ph on a Food Preservative

Experiment One: The Effect of pH on a Food Preservative

Organic Chemistry 2401

Lab of 9/13/16

Abstract:  Sodium benzoate was manipulated with HCl until a pH level of two or lower was reached. This mimicked an acidic solution found in the stomach and a white insoluble precipitate was separated and gathered. This resulted in sodium benzoate undergoing a chemical reaction that will not dissolve. It is advocated that the substance is benzoic acid. This will form within the human body (stomach); and further studies will be needed to test, if sodium benzoate, can still be a good source as a food preservative.

Shaneka Edwards

Due 9/20/16

Introduction:

A question was formed, “Does a new substance form when sodium benzoate is placed into a simulated stomach acid?” Sodium benzoate is what will be tested for the sake of any food product that contains sodium benzoate as a preservative. Based on an ad campaign, trying to slander the integrity of the corporation FFI, the campaign insinuated that Sodium benzoate does not remain the same component. Once the substance has reach the stomach, which contains stomach acid of high pH levels, the sodium benzoate will cause a chemical reaction which  causes a significant change to the sodium benzoate; this, brings rise to the question is this new substance, if formed harmful to the human body. Sodium benzoate is the salt form of benzoic acid, (Salt has always been used in history as a way to persevere food; the benzoic acid can be used as a food preservative. It is found that benzoic acid in salt form is much more soluble in water, this is the reason why this form is much more popular in preserving food today.) Is widely in food, but particularly found in acidic foods.

 However, sodium benzoate is more common in acidic foods for a reason, which brings about the theory that it will not be harmful in the body, when change is brought about when reacting to the stomach acid. Sodium benzoate maybe more helpful to the body then harmful; with the knowledge that, “benzoic acid is a natural preservative that inhibits the growth of bacteria, yeasts, and molds and thus retards spoilage”, can help stop any harmful bacteria that comes along with eating any other foods. The main purpose is to first explore the theory of sodium benzoate becoming a new substance when reaching high pH levels. Preferable a pH level that simulates the acid found in the stomach of a human body. It is very likely for change, to happen; when sodium benzoates experience a different pH level than its norm it will create a new substance.

To execute this theory, an acid will be added to the sodium benzoate. By adding the acid this will allow a stomach environment to be imitated. This can provoke change; if change will happen an indication will occur during this phase. Change of sodium benzoate by the acid can and will be indicted by the following: a color change, solids are formed, vapors, gas (bubbling) temperature change, acid changes to base or vice versa. If a precipitate is formed then this will confirm the pH level of the human stomach acid is able to perform the reaction of benzoic acid. To simplify what reactions are being searched are as follows: benzoate ion which is a weak base is combined with hydronium ion to produce benzoic acid. This will confirm that the protons have been transferred over from the strong acid to the weak base, which should be insoluble in water. This also confirms the reason why looking for a precipitate is necessary.

Materials and Methods:

        Part A; Sodium benzoate, 1.94g, was place into beaker. Water, 10mL, was added to sodium benzoate and stirred until contains dissolved.  3M Hydrochloric acid, 3.0mL, was poured into sodium benzoate solution, slowly. The solution was stirred and pH level was tested.  pH level appeared an orange-yellow color. 3M Hydrochloric acid, 2.25mL was added to sodium benzoate solution, slowly and stirred. Retested pH level appeared bright pink. Sodium benzoate solution was placed in an ice bath reducing the temperature, 9.8 Celsius. Sodium benzoate solution made an apparent change. Results were poured into Buchner funnel with filter paper. Beaker was rinsed out with cold water to remove residue, and poured into Buchner funnel. Vacuum was turned on until contains was dry. The drained liquid from separation was then poured over damp contains in Buchner funnel and filtered again. Filter paper was careful removed and placed on to watch glass. Substance, 27.11g, was place in oven. Substance was reweighed after 38 minutes, 23.9357g. Substance was reweighed for the third time after 17 minutes, 23.4937g. Complete dried substance was carefully empty into labeled vial and stored.