This report verified that sodium benzoate, when mixed with food in the quantities specified, was not injurious to the general health nor found to adversely affect or impair the quality or nutritive value of such food. Sodium benzoate may be used in food at levels not to exceed good manufacturing practice. Sodium benzoate is not recommended as a preservative at pH ranges higher than 4.5. It is generally accepted that the undissociated benzoic acid is the active antimicrobial agent. Although no definite theory has been yet proposed to explain this antimicrobial effect, it is believed to be related to the high lipoid solubility of the undissociated benzoic acid which allows it to accumulate on the cell membranes or on various structures and surfaces of the bacterial cell, effectively inhibiting its cellular activity.
Sodium benzoate has activity against yeast, mold, and bacteria.
Although several studies have been performed on the antimicrobial activity of sodium benzoate on these species, it is difficult to obtain substantial evidence on relative activities of sodium benzoate against specific members of those general species. Actual field application trials are recommended for assurance of satisfactory antimicrobial activity against the species in question. At low pH values, sodium benzoate may impart a slight tang in taste attributable to the undissociated benzoic acid. If this effect is undesirable, it may be overcome by using other approved preservatives in conjunction with sodium benzoate to lower the concentration of sodium benzoate below the taste threshold. An important consideration in preserving with sodium benzoate is the addition of the preservative as early as possible in the food processing.