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acids (SuE), propylene glycol esters of fatty acids (PGE) and sorbitan esters of fatty acids. Analysis of
these emulsifiers (MGL, SuE, PGE) uses 3,5-dinitrobenzoil chloride (DNBC) with the pre-column
method to form DNBC derivatives followed by separation with reversed-phase HPLC and UV detection
at 230 nm [147-149] and the method is applied for margarine, shortening, mayonnaise and ice cream
(Fig. 1.2.8). The detection limits of MG, SuE, PGE are 10 ppm, respectively.

Fig. 1.2.8.
Liquid chromatograms obtained from
several kinds of foods added to a
mixture of sucrose mono- and di-fatty
acid esters or not by the proposed
procedure: (a) added to the mixture;
(b) no addition. HPLC condition: column,
Inertsil C8 (4.6 mm i.d. × 250 mm); mobile
phase, 15% H O in CH CN (A) and
3
2
100% CH CN (B); Gradient (A) (ρ) (B)
3
for 30 min, following to (B) for 20 min.
Flowrate: 1.0 ml/min; detection: UV230
nm; injection: 20 µ1. (Reproduced from
ref. 148: J. Food Hyg. Soc Japan,
(1989) 30, p. 311, Fig. 5.).

1.2.3.5—
Other Food Additives

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