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Twenty‐one commercial pisco samples made with Quebranta grapes from four different geographical areas in Peru have been evaluated by gas chromatography–olfactometry (GC‐O) and chemical quantitative analysis. The GC‐O study revealed that the Peruvian pisco from the Quebranta grape variety has a relatively simple aroma profile formed by 22 odorants, all of which could be identified. Most of the odorants are fermentation related, while guaiacol, β‐damascenone, geraniol and linalool come from the grape. The chemical analysis of the volatiles of these samples has shown a volatile profile quite typical of a wine distillate, with not very high but perceptible levels of linalool and β‐damascenone (up to 46 µg/l). Some of the samples contained also very high levels of β‐phenylethyl acetate and β‐phenylethanol (up to 13 mg/l and 72 mg/l, respectively), which arises as key aroma compounds potentially responsible for deep sensory differences between samples. In fact, the differential sensory character of piscos from the Moquegua region can be explained by the lowest levels of β‐phenylethyl acetate, β‐phenylethanol, β‐damascenone and linalool and also by the highest level of ethyl acetate. In general, differences linked to the geographical area are not very big, although results suggest that the difference could be enough for classification. Copyright © 2012 John Wiley & Sons, Ltd.

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Forty‐five samples of commercial pisco made with Albilla, Muscat and Torontel grapes in different areas of Peru have been evaluated by gas chromatography–olfactometry (GC‐O) and chemical quantitative analysis. The GC‐O study revealed that the Peruvian pisco made of these varieties of grapes has an aroma profile formed by nearly 30 odorants. The odorant 2,3‐pentanedione was detected only in the Albilla sample, producing significant differences. The chemical analysis of the volatiles of these samples showed volatile profiles quite typical of a wine distillate. The Torontel samples (considered the most aromatic variety) were marked by high levels of terpenes and β‐damascenone, the Albilla samples showed the lowest values of terpenes, which may explain their low scores obtained during the sensory analysis, while the Muscat samples showed intermediate levels of this family of compounds and were characterized by high concentrations of benzyl alcohol and β‐phenylethanol. Furthermore, an evaluation of the sensory contribution of terpenes in these piscos was carried out, demonstrating that linalool is the most odour‐active terpene, exceeding its odour threshold in 34 out of 45 piscos analysed. However, the other terpenes should also be considered as important contributors to the aroma of piscos because a certain degree of cooperation between the components of this family has been demonstrated. The quantitative analysis data allowed us to distinguish pisco samples according to their variety and could explain some sensory differences observed depending on the nature of the grapes. Copyright © 2013 John Wiley & Sons, Ltd.

Veintiuna muestras de pisco comercial elaboradas a partir de uvas de la variedad Quebranta en cuatro de las mayores regiones pisqueras de Perú han sido analizadas por Cromatografía de Gases-Olfatometría (GC-O) y análisis químico cuantitativo (GC-FID y GC-MS). El estudio olfatométrico ha revelado que el pisco peruano de la variedad de uva Quebranta posee un perfil aromático relativamente sencillo formado por 22 odorantes, (todos ellos se han podido identificar sin problema). La mayoría de estos odorantes detectactos están relacionados con la fermentación, con alguna excepción, como es el caso del guaiacol, la -damascenona, el geraniol y el linalool, que proceden de las uvas. El análisis químico de los compuestos volátiles de estas muestras ha mostrado un perfil volátil típico de un destilado de vino, con niveles no muy altos pero perceptibles de linalool, geraniol y -damascenona. Aunque cabe destacar que estas muestras de pisco han presentado niveles muy superiores de -feniletanol, isobutanal y acetato de etilo que los encontrados en otros destilados del vino, como grappas y orujos. Algunas de las muestras analizadas contienen también muy altas cantidades de acetato de -feniletilo (hasta 13 μg L-1), que surge como un compuesto aromático clave potencialmente responsable de las diferencias sensoriales entre muestras. De hecho, los bajos niveles de este compuesto, junto con los también bajos niveles de -feniletanol, -damascenona y linalool pueden explicar las diferencias encontradas desde el punto de vista sensorial entre los piscos de la región de Moquegua y el resto. En general, las diferencias vinculadas a la distribución geográfica no son muy grandes, aunque los resultados sugieren que podría ser suficiente para su clasificación.