In-Plant Assessment of Peruvian Pisco Distillates Using Infrared Sensing Technologies

A novel approach using portable Fourier transform infrared spectroscopy (FT-IR) with an attenuated total reflectance accessory was developed to screen the quality of Pisco distillates. Pisco samples (n = 188) were obtained from distilleries in Peru, and their quality was determined by gas chromatography. FTIR discriminated the three distillate fractions (head, body, and tail) of Pisco, identifying their alcohol fingerprint (3091-2660 cm^-1 and 1190-821 cm^-1) as contributing to the class differentiation. Partial least squares regression showed strong correlations (R_pre = 0.93-1.00) and low errors of prediction (RMSEP) in quantifying 6 key quality components (ethanol, methanol, acetaldehyde, acetic acid, furfural, and titratable acidity). This approach offers a scalable alternative to conventional empirical methods, enabling distilleries to make precise distillation cuts, reduce production costs, and ensure consistent product quality. This is the first report of a portable FT-IR system capable of in-line monitoring of key quality parameters in the spirit distilleries.