Determination and prediction of odor thresholds for odor active volatiles in a neutral apple juice matrix

Odor thresholds were determined for 10 odor active compounds (OAC) in apple juice, using three-alternate forced choice methodology. Thresholds were determined in a neutral juice matrix by 25-30 panelists in duplicate at 22C. Individual thresholds were calculated using the best estimate threshold method. Group thresholds were determined using the geometric mean of the individual thresholds. OAC differed substantially in their concentration ranges, aroma thresholds (0.06-5.49μL/L) and response rates (1.5-234.5% correct response/[μL/L]). Juice thresholds exceeded water thresholds by ∼5-600 times. Multiple linear regressions were used to develop models to predict juice thresholds from water thresholds and physical constants, for apple juice (AJ) and published orange juice (OJ) values. The simplest most practical models utilized just one variable, the logarithm of the water threshold. Coefficients of correlation (R2) for the AJ and OJ models were 71.7 and 72.8%, respectively, and provided satisfactory estimates of juice thresholds. © 2011 Crown in the right of Canada.