Ricerc@Sapienza

Many analytical methods for polyphenol determination in food and beverages can be found in the literature, but most
of them need time-consuming sample pretreatment. Conversely, methods are missing for a rapid screening of non-pre-treated
samples, with useful application in the agri-food industry, from process control to fraud. Selected ion recording mass mode after
liquid chromatographic separation was used for the detection and quantification of free polyphenols in three craft beers, after just
degassing, filtering, and diluting the beer samples with the mobile phase prior to the analysis. Fourteen polyphenols including
hydroxybenzoic acids, hydroxycinnamic acids, and flavonols were chosen as standards. Nine of them were identified and quantified
in at least one of the analyzed craft beers, despite the low content and the complexity of the samples. Depending on the analyte, 80−
7 μg/L as the limit of detection (LOD) and 240−30 μg/L as the limit of quantification (LOQ) were found. Satisfactory results for
interday and intraday precisions, accuracy, recovery, and matrix effect were found. The one-factor analysis of variance (ANOVA) on
the three different craft beers was statistically significant, with P < 0.05. The electrospray ionization mass fingerprinting of the same
non-pre-treated craft beers was also investigated for wider characterization. Diagnostic ions were found and identified as deriving
from oligosaccharides, organic acids, and amino acids.