2405, 2022

Temporal ranking for characterization and improved discrimination of protein beverages

John Castura/ May 24, 2022/ Peer-reviewed Paper/ 0 comments

We propose a new temporal sensory method called temporal ranking (TR) in which assessors indicate and rank the three most noticeable sensations at every time point. The TR method was compared to temporal-check-all-that-apply (TCATA) in two trained-panel studies, one study involving six ready-to-mix (RTM) protein beverages and one study involving seven ready-to-drink (RTD) protein beverages. In each study, the same

0403, 2022

Clustering consumers based on product discrimination in check-all-that-apply (CATA) data

John Castura/ March 4, 2022/ Peer-reviewed Paper/ 0 comments

Consumers can be clustered based on their product-related check-all-that-apply (CATA) responses. We identify two paradoxes that can occur if these clusters are derived from conventional similarity coefficients. The first paradox is that clustering similar consumers can nullify within-cluster sensory differentiation of products. The second paradox is that consumers who check many attributes yet disagree can be clustered together, whereas consumers

0102, 2022

Discriminability and uncertainty in principal component analysis (PCA) of temporal check-all-that-apply (TCATA) data

John Castura/ February 1, 2022/ Peer-reviewed Paper/ 0 comments

Temporal check-all-that-apply (TCATA) data can be summarized and explored using principal component analysis (PCA). Here we analyze TCATA data on Syrah wines obtained from a trained sensory panel. We evaluate new and existing methods to explore the uncertainty in the PCA scores. To do so, we use the bootstrap procedure to obtain many virtual panels from the real panel’s data.

0107, 2019

Does the τ estimate from same-different test data represent a relevant sensory effect size for determining sensory equivalency?

John Castura/ July 1, 2019/ Peer-reviewed Paper/ 0 comments

Analysis of data arising from the same-different test method can be submitted to Thurstonian-derived modelling with the goal of estimating the sensory distance between two products (the discriminal distance δ) and the response bias for responding “same” (τ). Previously it has been proposed that it is possible to use τ estimates from same-different test data to represent the consumer-relevant effect

1505, 2019

Did assessors select attributes by chance alone in your TDS study, and how relevant is it to know?

John Castura/ May 15, 2019/ Peer-reviewed Paper/ 0 comments

Dominance rates arising from Temporal Dominance of Sensations (TDS) data are almost always plotted and understood with reference to chance and significance lines, which are based on the assumption of random attribute selection. These lines are auxiliary to the chart, and used to interpret the dominance rates; when the dominance rate for some attribute exceeds the significance line, the conventional

1402, 2019

Influence of wine composition on consumer perception and acceptance of Brettanomyces metabolites using temporal check-all-that-apply methodology

John Castura/ February 14, 2019/ Peer-reviewed Paper/ 0 comments

Brettanomyces spoilage in wine is due to the production of metabolites, which together create the distinctive ‘Bretty’ aroma and flavor profile associated with wine. The objective of this study was to assess the influence of three wine flavor matrices on consumer acceptance and the temporal sensory properties of wines containing high and low concentrations of Brettanomyces-metabolites. A commercial Shiraz red

1506, 2018

How task instructions affect performance on the unspecified tetrad test

John Castura/ June 15, 2018/ Peer-reviewed Paper/ 0 comments

This parallel‐groups study (n = 1,857) investigates compliance of untrained assessors with tetrad instructions. Stimuli are four unique color swatches that differ only in their green chromaticities. Results confirm that the swatches used in this study were generally perceived as nonconfusable visual stimuli ordered A, B, C, D, and that AB and CD were more different than BC. These stimuli thus modeled

3004, 2018

The analysis of temporal check-all-that-apply (TCATA) data

John Castura/ April 30, 2018/ Peer-reviewed Paper, Type/ 0 comments

Temporal check-all-that-apply (TCATA) extends classical check-all-that-apply (CATA) by adding a temporal dimension to the evaluation. From a data analysis point of view, TCATA data are similar to Temporal Dominance of Sensations (TDS) data but differ in that more than one attribute can be selected at any time point. Procedures for analyzing TCATA data can hence be generalized from methods for

0103, 2018

What is dominance? An exploration of the concept in TDS tests with trained assessors and consumers

Sara King/ March 1, 2018/ Peer-reviewed Paper/ 0 comments

TDS describes the evolution of the dominant sensory attributes during consumption. Dominance can be assessed as the sensation that captures the attention, the most striking, or the new sensation that pops up, but not necessarily the most intense. This wide definition implies that individual assessors within a panel might assess dominance differently, and even the same assessor could be using