Quantification of Hexanal in Potato Chips

A headspace-solid-phase microextraction (HS-SPME) followed by GC–FID analysis (Agilent 7820A GC System, Palo Alto, CA, USA) was proposed in this work for the quantification of the hexanal content of chips [42 (link)]. First, 1.00 ± 0.01 g of grounded chips was prepared and then 2 mL of saturated NaCl and 20 µL of the internal standard (4-methyl-2-pentanone, 8 mg kg⁻¹) was added into the SPME vial with a micro-stirring bar. In accordance with the literature, a DVB/CAR/PDMS SPME fiber for the adsorption of polar and nonpolar volatile compounds was used (Supelco, Bellefonte, PA, USA) [43 (link)]. The sample vial was placed in a water bath at 50 °C with a stirring of 500 rpm. First, 10 min of equilibration under these conditions was required. Then, the extraction was carried out during 30 min in which the fiber was exposed before its desorption during 12 min into the GC injector port at 250 °C. The splitless mode was selected in this step. The GC–FID equipment was an Agilent 7820 AGC System (Palo Alto, CA, USA) equipped with a SPB-5 column programmed in two ramps: (a) from 50 °C to 70 °C (hold 1 min) at 5 °C min⁻¹ and (b) from 70 °C to 200 °C (hold 10 min) at 35 °C min⁻¹. The carrier gas was helium at 1 mL min⁻¹ and the FID temperature was 300 °C. Working solutions obtained from an hexanal stock prepared at 30 mg kg⁻¹ in distilled water were used for the external calibration.