Use of 1H nuclear magnetic resonance and chemometrics to detect the percentage of ethanol anhydrous in Brazilian type C premium gasoline

•Ethanol levels out of range are the main irregularities in Brazilian gasoline.•NMR spectra are sensitive to variation in the ethanol level of Premium gasoline (PG).•NMR-PCA for distinguishing between conforming and non-conform PG samples.•SIMCA and PLS to classify and estimate the ethanol content of different PG samples.•Fast and non-destructive analytical method for Brazilian premium gasoline analysis.