Development of HPLC and NACE methods for the simultaneous determination of benzoic and sorbic acids in sour snap beans containing oil

Abstract

The practical methods were developed for the simultaneous determination of benzoic acid (BA) and sorbic acid (SA) in sour snap bean samples containing oil. BA and SA in the samples were extracted by ultrasonication with water, followed by cleanup procedures with precipitation for removing the potential proteins and with petroleum ether liquid-liquid extraction for removing the edible oil contained in the samples. The HPLC method was developed using Supelco C18 (250 mm x 4.6 mm id, 5 microm) as column, MeOH-20 mM NH(4)Ac (25:75 v/v) at 1.0 mL/min as the mobile phase and 230 nm as the detection wavelength. The optimal NACE method was established with a running buffer of 20.0 mM NH(4)Ac in 95% MeOH (pH* 10.6), and an applied voltage of -30 kV over a capillary of 50 microm id x 48.5 cm (40 cm to the detector window), which gave a baseline separation of BA and SA, and as well as of the blank matrix within ca. 10 min. Both HPLC and NACE methods gave the relatively lower limits of quantification at about 0.01-0.02 and 0.04-0.05 mg/kg, respectively, whereas the overall recoveries were larger than 85.0%. The proposed methods have been successfully applied to measure 15 real sour bean samples and the content profile of BA and SA in sour bean samples was obtained and evaluated.

Food analysis: A continuous challenge for miniaturized separation techniques

“…In the field of food quality, in recent years, CE has been a fundamental technique broadly applied for the analysis of protein profiles, proteins, amino acids, immunoglobulins and peptides 55–74 and antioxidant compounds 75–89. To a lesser extent, it has also been useful for the determination of organic acids 90–96, inorganic ions 97–99, carbohydrates 100–103 and other compounds such as salicylaldehyde 104, sorbate and benzoate 105, folic acid 106, saccharine and aspartame 107, glucosinolates 108 and water‐soluble vitamins 109 in different kinds of food matrices. Analysis of amino acids is also essential in food analysis, due to the information it can provide concerning food quality, adulteration, protein composition, etc .…”

“…Organic acids have also been analyzed by CE 90–96. It is especially significant the fact that three of these works employed CTAB as a component of the BGE with the aim of reverse EOF and reduce analytical time 94–96.…”

Development and Validation of Nonaqueous Capillary Electrophoresis Method for Simultaneous Estimation of Icariin, Icariside II, and Epimedin K in Epimedium Leaves

“…However, MEKC displayed some defects with longer migration time and complicated background electrolyte (BGE) composition. Nonaqueous CE (NACE), as an important CE separation mode Liu, Song, Han et al 2006;Han et al 2007), is performed in the BGE with an organic solvent medium; it can improve the separation resolution and the reproducibility of the method, due to the presence of the great difference of physicochemical properties between organic and water solvent. However, the analysis for flavonoids in Epimedium species by NACE has not been extensively documented.…”

Simultaneous Separation and Determination of Benzoic Acid Compounds in the Plant Medicine by High Performance Capillary Electrophoresis

“…Only some of them or similar to them have been described. [11][12][13][14][15][16][17][18][19][20][21] In this investigation the several parameters that influence the separation were investigated including pH, concentration of buffer and applied voltage. However, it is generally tedious procedure to search for the optimal conditions.…”