Determination of Lemon Juice Adulteration by Analysis of Gas Chromatography Profile of Volatile Organic Compounds Extracted with Nano-Sized Polyester-Polyaniline Fiber

Abstract

Nano-sized polyaniline (50–150 nm) has been prepared by polymerization of aniline on the surface of the commercial polyester fiber. A method for determination of adulteration in lemon juice samples was developed. Solid-phase microextraction (SPME) by polyester-polyaniline fiber to extract volatile organic compounds (VOCs) and analysis of gas chromatography (GC) profile were used. The effects of industrial lemon juice (ILJ) percent, organic lemon juice (OLJ) percent, and storage time of lemon juice as tree variable factors on the gas chromatography profile were studied. D-optimal combined design (DOCD) was applied to design the experiments that study the gas chromatography profile. For this purpose, the recorded chromatograms of VOCs were divided into four-time sections (0–5, 5–10, 10–15, and 15–20 min) and the peak number, total peak height, and total peak area in the four divided time sections were analyzed. The results were analyzed, and statistical test of correlation and linear regression was used. Results showed that there is good relation between industrial lemon juice percent, organic lemon juice percent, and storage time and peak characters (peak numbers, total peak height, and total peak area) in the divided time sections of each chromatogram. So, the presented method is a good method to find adulteration in organic lemon juice by gas chromatography profile analysis.