Eficiencia de las pruebas discriminatorias para reportar diferencias cuando se utilizan consumidores ecuatorianos
Efficiency of discrimination tests on ecuadorian consumers to find out differences
Resumen
En las pruebas de diferencia el desempeño de los jueces varía en función de la prueba utilizada. Pilsener y Brahma, dos cervezas producidas en el Ecuador, fueron utilizadas como estímulos en el estudio. Un grupo de 121 consumidores realizaron las cuatro pruebas de diferenciación: dúo-trío, triangular, igual- diferente y ABX. El objetivo de este artículo fue evaluar la eficacia de las pruebas de diferencia en consumidores ecuatorianos. Los datos fueron analizados por la metodología tradicional y mediante la aplicación del modelo thurstoniano. El ensayo ABX obtuvo el mayor número de aciertos (76), seguida por la dúo- trío, igual-diferente y finalmente la triangular. Se encontró diferencia significativa para todas las pruebas (α= 0.05). El análisis de la frecuencia de aciertos de cada juez reveló que sólo ocho evaluadores acertaron en los cuatro ensayos empleados. La prueba ABX tuvo la mayor magnitud percibida en los estímulos confundibles, con un valor d’ de 1,32. El análisis a partir del modelo de Thurstone brindó la posibilidad de comparar las cuatros pruebas a partir de los d’ obtenidos, esta es una medida fundamental e independiente de la metodología sensorial utilizada.
Abstract
In discrimination tests the performance of judges varies depending on the test used. Brahma and Pilsener, two beers produced in Ecuador, were used as stimuli in the study. A group of 121 consumers conducted four discrimination tests: duo-trio, triangle, same-different and ABX. The purpose of this paper was to evaluate the efficacy of sensory discrimination tests on ecuedorian consumers. The data were analyzed by the traditional methodology and by applying the Thurstonian model. The ABX test achieved the highest number of hits (76), followed by the duo-trio, same-different and finally the triangular. All tests were significantly different (α= 0.05). The analysis of the frequency of hits of each panelist revealed that only eight evaluators answered correctly in the four tests used. The ABX test had the highest perceived magnitude confusable stimuli, with a value d’ of 1.32. The analysis from Thurstone model provided an opportunity to compare the four tests from d’ obtained, which is a fundamental and independent measurement in sensory methodology applied.
Key words: Sensory evaluation, discrimination tests, Thurstonian model.
Citas
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