Determination of the effect of concentration of Sodium Benzoate in Fruit Juice containing Ascorbic acid

Background: This research was designed to determine the influence of the concentration ratio of sodium benzoate on the ascorbic acid (vitamin C) content of orange juice and to determine the concentration of sodium benzoate in which the reaction is effective concerning storage duration.

Methods: This was achieved by measuring the concentration of ascorbic acid used in its reaction with sodium benzoate using iodometric titration as described by AOAC 2000.

Results: It was deduced that when a high amount of sodium benzoate (preservative) was added to ascorbic acid (vitamin C) enriched fruit juice or beverages, the high concentration of this preservative caused the reduction of ascorbic acid level due to decarboxylation reaction with benzoic acid. It was also observed that it was safer to use a trace amount of sodium benzoate (between 100 to 150 mg) as observed in the reaction potency curve. This amount coincided with the prescription given by the Food and Drug Administration Agency (FDA) as the maximum allowance of sodium benzoate used as a preservative in the formulation of a beverage.

Conclusion: It was concluded that benzoic acid, an active form of sodium benzoate (preservative) when reacted with ascorbic acid in fruit juice was reduced to a potential carcinogen known as benzene. And as the reaction gradually proceeded, the ascorbic acid content diminished.