Gas Chromatographic Approaches for the Determination of Phenolic Acids in Foods, Plants, and Plant-Based Foodstuffs: A Comprehensive Review

Phenolic acids (PAs) are among the most abundant phytochemicals in foods and plants, and their consumption is increasing due to well-established health benefits. Determining these compounds is challenging because of their structural diversity, wide concentration ranges, and complex matrices. This review summarizes the separate analysis of PAs in foods, plants, and plant-based foodstuffs, with a particular focus on gas chromatography (GC) methodologies. Since PAs are inherently nonvolatile, chemical derivatization is generally required to enhance volatility and reduce polarity, enabling accurate detection. The role of derivatization, together with the extraction approaches used to isolate PAs from complex matrices, is critically discussed. Additionally, the review covers key method validation parameters, such as analytical range, limit of detection, and limit of quantification, that are essential for accurate measurement of PAs. By focusing on GC-based approaches, this review highlights their contribution to improving analytical performance and supporting research on PAs in food and plant sciences.