Table 1. Summary of analytical methods for butyric acid

Analytical method	Main advantages	Main limitations	Suitable sample types / situations	References
GC / GC-MS	Excellent separation of volatile fatty acids and high quantitative reproducibility	Unmodified butyric acid may show unstable retention and peak shape; derivatization is often needed	Feces, fermentation broths, dairy products, volatile fatty acid mixtures	Amirav et al., 2008; Wang et al., 2020; Gu et al., 2021; Lewis et al., 1967
HPLC	Flexible for diverse matrices and applicable to non-volatile or thermally labile compounds	Butyric acid has weak UV absorbance, so detector choice and derivatization are critical	Organic acid profiling, food matrices, selected biological samples	Chen and Lifschitz, 1989; De Baere et al., 2013
LC-MS/MS / HRMS	High selectivity in complex matrices and strong capability for low-level simultaneous analysis	High instrument cost, operational complexity, and ionization-related issues for small molecules	Plasma, urine, complex foods, high-precision analysis	Chen et al., 2021; Mosen et al., 2021
Derivatization-based methods	Improves sensitivity, selectivity, and detection stability	Adds time to sample preparation and increases reagent-dependent variability	Low-concentration butyric acid and samples difficult to analyze directly	Gu et al., 2021; Jiang et al., 2025; Kim et al., 2019
Headspace / distillation-based approaches	Reduces matrix interference by isolating volatile components effectively	Additional preparation steps are required, and recovery must be controlled	Feces, foods, fermentation samples, volatile-rich matrices	Cruwys et al., 2002 Park et al., 2026