Development and Validation of An Spanish Labeled Magnitude Scale For Sweetness Evaluation

Abstract

A labeled magnitude scale (LMS) in spanish language was developed and validated to assess sweetness. The LMS allows assessors to make their estimates with respect to the greatest imaginable sweetness. LMS offers a continuum, anchored in verbal descriptors ranging from slightly detectable/"ligeramente detectable" to the greatest imaginable/"lo más grande imaginable”. The analysis showed that five descriptors: weakly sweet (“WE”/"débilmente dulce”), moderately sweet (”MO”/"moderadamente dulce”), fairly sweet (“FA”/"bastante dulce"), very sweet (“VE”/"muy dulce") and greatest imaginable sweetness (“GI”/"dulzor más grande imaginable") were the main contributors to make this scale. The average values assigned to these descriptors indicate that "WE," "MO," "FA" and "VE" represent 5, 18, 31 and 43% of the sweetness scale, and finally "GI" was to be placed at the top, at 100% of the scale. This LMS scale was applied to measure sweetness of sucrose and Stevia rebaudiana extracts which were also evaluated by magnitude estimation (ME) and another general LMS (gLMS) in the context of evoked oral sensation. Significant differences in the rate of growth of sweetness appears for both compounds, where sucrose showed more steeper functions than S. rebaudiana extract. Comparying with ME, sweetness ratings with LMS show a steepness concentration-response function. Finally, rates of growth of sweetness functions obtained with ME and gLMS, were similar, yielding ratio-level data.