|Title||Principal component analysis of tie-intensity bitterness curves|
|Source||Journal of Sensory Studies 8 (1993)4. - ISSN 0887-8250 - p. 317 - 328.|
|Publication type||Refereed Article in a scientific journal|
Perceived bitterness in drinks is known to fade slowly over time. Time‐Intensity curves are a means of studying this fading process. K subjects record the perceived bitterness intensity by moving a slider on a monitor using a mouse. Usually average TI‐curves are calculated to give a representation of the TI‐curve for one particular object. The problem is that there often are large individual differences, so the average TI‐curve is not always a good representation. An alternative is to perform a Principal Component Analysis on the matrices of objects by individual TI‐curves for each object. The resulting, so‐called, Principal Time Intensity Curves (PTIC's) are better representations than the average curves. Often the PTIC's for the different products are hard to distinguish. In this case a noncentered PCA of the matrix with curves gives results which show more differences between the products.