Agricultural and Biosystems Engineering Publications

Quantification of Carbonyl Compounds Generated from Ozone-Based Food Colorants Decomposition Using On-Fiber Derivatization-SPME-GC-MS

Wenda Zhu, Iowa State University
Jacek A. Koziel, Iowa State University
Lingshuang Cai, Iowa State University
H. Duygu Özsoy, Iowa State University
J. (Hans) van Leeuwen, Iowa State University

This article is from Chromatography 2 (2015): 1–18, doi:10.3390/chromatography2010001. Posted with permission.

Abstract

Fruit leathers (FLs) production produces some not-to-specification material, which contains valuable ingredients like fruit pulp, sugars and acidulates. Recovery of FL for product recycling requires decolorization. In earlier research, we proved the efficiency of an ozone-based decolorization process; however, it produces carbonyls as major byproducts, which could be of concern. A headspace solid-phase microextraction with on-fiber derivatization followed by gas chromatography-mass spectrometry was developed for 10 carbonyls analysis in ozonated FL solution/suspension. Effects of dopant concentration, derivatization temperature and time were studied. The adapted method was used to analyze ozonated FL solution/suspension samples. Dopant concentration and derivatization temperature were optimized to 17 mg/mL and 60 °C, respectively. Competitive extraction was studied, and 5 s extraction time was used to avoid non-linear derivatization of 2-furfural. The detection limits (LODs) for target carbonyls ranged from 0.016 and 0.030 µg/L. A much lower LOD (0.016 ppb) for 2-furfural was achieved compared with 6 and 35 ppb in previous studies. Analysis results confirmed the robustness of the adapted method for quantification of carbonyls in recycled process water treated with ozone-based decolorization. Ethanal, hexanal, 2-furfural, and benzaldehyde were identified as byproducts of known toxicity but all found below levels for concern.