Page 96 - Analytical method for food addtives

7

E210–13: Benzoic acid

7.1 Introduction
Benzoic acid is used as a preservative in a wide variety of foods. Benzoic acid
retards the growth of yeast and moulds, the effective agent being the undissociated
acid. The major food groups contributing to dietary intake of benzoic acid are a
wide variety of foods permitted at the following levels; various foods 200–
1000 mg/kg (prepared salads, confectionery, etc. 1500 mg/kg; food supplements,
preserved vegetables 2000 mg/kg; liquid egg 5000 mg/kg; cooked seafood 2000–
6000 mg/kg) and soft drinks 150 mg/kg, alcohol-free beer 200 mg/kg (Sacramental
grape juice 2000 mg/kg, liquid tea concentrates 600 mg/kg). The acceptable daily
intake (ADI) for benzoic acid is 5 mg/kg body weight.

7.2 Methods of analysis
There are numerous methods published for the determination of benzoic acid in
foodstuffs. The majority of these methods are separation methods. Methods that
have been developed for benzoic acid in foodstuffs include gas chromatography
1–7
(GC), high pressure liquid chromatography (HPLC), 8–19 micellar electrokinetic
20
chromatography(MECC), the use of lanthanide-sensitised luminescence, 21
22
spectrophotometric, high performance thin layer chromatography (HPTLC), 23
24
and potentiometric. A summary of these methods is given in Table 7.1, together
with the matrices for which the methods are applicable. If statistical parameters for
these methods were available these have been summarised in Table 7.2. Two of
these methods are AOAC Official Methods of Analysis and both have been
1,8
collaboratively tested.