John C. Castura

• Compusense Inc.

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 i...

Check-all-that-apply (CATA) questionnaires have seen a widespread use recently. In this paper, we briefly review some of the existing approaches to analyze data obtained from such a study. Proposed extensions to these methods include a generalization of Cochran's Q to test for product differences across all attributes, and a more informative penalt...

A unified framework is provided for analysing check-all-that-apply (CATA) product data following the ``one citation, one vote" principle. CATA data arise from studies where A consumers evaluate P products by describing samples by checking all of the T terms that apply. Giving every citation the same weight, regardless of the assessor, product, or t...

Principal component analysis (PCA) is often used to explore sensory and consumer test data about products on multicollinear sensory attributes. In this paper, we propose an approach for investigating paired comparisons between products and their uncertainties in the principal components. We use the truncated total bootstrap (TTB) procedure to simul...

Gin is a distilled spirit characterized by juniper flavor, often accompanied by other botanical flavors. The objective of this research was to use gin as a case study to compare temporal dominance of sensations (TDS), temporal check‐all‐that‐apply (TCATA), and temporal ranking (TR). Trained panelists used each of these methods to evaluate the tempo...

Chocolate-flavored milk contributes to excessive intake of added sugars among children and adolescents, which why it is a good candidate product for sucrose replacement. This study investigates how replacing sucrose partially or completely with different sweetener systems affects the sensory profile and consumer liking. Five chocolate-flavored milk...

Cluster analysis is often used to group consumers based on their hedonic responses to products. We give a motivating example in which conventional cluster analyses converge on a solution where consumers do not agree on which products they like. We show why this occurs. We state a goal: to group together consumers who have a shared opinion of which...

Brewer's spent grain (BSG), a by-product of the brewing industry, has great potential as food additive. BSG is particularly rich in protein and fibre content which makes it an ideal nutritional fortifier for biscuits. However, adding BSG to biscuits can lead to changes in sensory perception and consumer acceptance. This study explored the temporal...

This study investigated sweet–sour taste interactions in novel sweeteners using a 3 × 2 factorial design consisting of Sweetening System (three levels: sucrose; d ‐allulose; and a blend of d ‐allulose and Monk fruit extract) and Acidity (two levels: with or without citric acid). 110 untrained Chinese subjects participated using the temporal check‐a...

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 se...

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...

Temporal Dominance of Sensations (TDS) and Temporal Check-all-that-Apply (TCATA) from three different case studies are compared by means of canonical correlation analysis, orthogonalization and principal component analysis of the vertically unfolded data (which means that the matrices compared have samples*timepoints in the rows and attributes in t...

A graph theoretic approach is applied to investigate perception dynamics in the Sensometrics 2018 Data Analysis Workshop data sets. First, temporal check-all-that-apply (TCATA) data are investigated: ten sensory attributes are modelled as vertices and concurrent perception as edges, the size and width of each corresponding to the momentary elicitat...

Consumption of alcohol is widespread throughout much of the world, impacting human health and well-being in several ways. Taste (bitterness, sourness, saltiness, sweetness, umami, and oleogustus) is an important driver of consumer preference and intake for many foods and beverages. Here, we report on two studies; the first (S1) assesses general sen...

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 (thediscriminal 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 t...

Thermal taste status (TTS) describes a phenotype whereby some individuals experience a thermally-induced taste on thermal stimulation of the tongue (thermal tasters; TTs) and some do not (thermal non-tasters; TnTs). TTs experience a range of orosensations elicited by aqueous solutions and some beverages more intensely than TnTs. Whether this extend...

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 attrib...

Temporal sensory methods are used to allow consumers to characterize products dynamically, according to sensory attributes, emotional responses, or hedonic responses. Methodologies are reviewed and their limitations discussed. Obtaining information regarding dynamic perception from consumers not only permits investigation of how products are percei...

This chapter considers statistics used in sensory difference testing from the perspective of business objectives and risks. Selection of an appropriate test method and experimental design must be aligned such that data analysis is able to provide meaningful information that relates back to the business objective and, where applicable, provides an a...

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 differentl...

Despite the several differences in ingredients, processes and nutritional values, dairy foods as yogurts, fermented milks and milk beverages are widely accepted worldwide, and although they have their sensory profiling normally covered by descriptive analyses, the temporal perception involved during the consumption are rarely considered. In this se...

Temporal Check-All-That-Apply (TCATA), and its variant TCATA Fading, are extensions of Check-All-That-Apply (CATA) questions that can deliver detailed descriptions of the dynamics of the sensory characteristics of samples throughout consumption. This research contributes to establishing guidelines for best practice of TCATA methods and focuses on t...

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 we...

Temporal check‐all‐that‐apply (TCATA) is a rapid method where attributes are actively checked and unchecked to track sensations over time, so that the checked words fully describe the sample in any given moment. Here, we characterize the temporal profiles of sweeteners using TCATA. In two experiments, sweeteners were tested in water at concentratio...

The aim of the present work was to compare static and dynamic sensory product characterizations based on check-all-that-apply (CATA) questions with consumers. Three studies involving a total of 310 consumers were carried out. In each study, a between-subjects experimental design was used to compare static sensory characterizations obtained using CA...

Temporal Dominance of Sensations (TDS) and Temporal Check-all-that-apply (TCATA) are two multi-attribute methods for dynamic sensory characterization. Previous research has shown that both methodologies provide complementary information. However, it remains an open question which of the two approaches better explains consumers' hedonic perception o...

Several methods exist in order to profile complex matrices that change over time. In this study, two descriptive methodologies, descriptive analysis (DA) and temporal check-all-that-apply (TCATA) were used to analyze the complex perceptions associated with carbonation and compare the profiles from each method. To accomplish this, eleven sparkling w...

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 d...

Temporal Check-All-That-Apply (TCATA) Fading is a variant of TCATA where selected terms gradually and automatically become unselected over a predefined period of time and assessors are asked to re-select the terms if they still apply. Gaps in the temporal profile for a TCATA term may arise if assessors do not immediately re-select a fully faded ter...

Temporal Check-All-That-Apply (TCATA) is a multi-attribute temporal approach that extends CATA questions. It is based on continuous selection of the sensory attributes that are perceived as applicable for describing a focal sample during consumption. Compared to CATA, TCATA is a relatively intense and demanding task for consumers who have to focus...

In sensory evaluation, it may be necessary to design experiments that yield incomplete data sets. As such, sensory scientists will need to utilize statistical methods capable of handling data sets with missing values. This article demonstrates the advantages of a model‐based imputation procedure that simultaneously accounts for heterogeneity while...

Temporal Check-All-That-Apply (TCATA) has been recently introduced as a method for temporal sensory product characterization. This method requires assessors to select all the terms they consider applicable at each moment of the evaluation, and to de-select terms when they are no longer applicable. In the present work a variant of TCATA, TCATA Fadin...

Temporal Check-All-That-Apply (TCATA) is a new dynamic sensory method for which analysis techniques are still being developed and optimized. In this study, TCATA methodology was applied for the evaluation of wine finish by trained panelists (n = 13) on Syrah wines with different ethanol concentrations (10.5% v/v and 15.5% v/v). Raw data were time s...

Approaches for analyzing temporal check-all-that-apply (TCATA) data are further developed and illustrated using data arising from a Syrah wine finish evaluation. Raw and smoothed trajectories are obtained using principal component analysis. Virtual panels are obtained from a partial bootstrap, and the attribute citation proportions are then project...

The objective of this study was to determine if data capture device type had a significant influence on sensory descriptive analysis results. 12 trained assessors evaluated 4 snack bar products in triplicate on each of three devices (iPod, iPad, external monitor). Four‐way univariate analysis of variance detected no significant product by device in...

Methodologies for evaluating panel repeatability in Check-All-That-Apply (CATA) questions are reviewed and developed. First, the limitations with using McNemar's test as suggested elsewhere for the evaluation of repeatability are demonstrated through simple examples. Alternative approaches are then suggested and discussed. These include the binomia...

For the check-all-that-apply (CATA) question format, it is good practice to vary the attribute list order between evaluations to account for possible (and likely) position bias in the data. If attribute lists are to be randomized, the question is how to allocate these attribute lists orders. Some authors recommend a "to samples" allocation order, r...

Temporal Check-All-That-Apply (TCATA) is introduced as a new dynamic method for describing multidi-mensional sensory properties of products as they evolve over time. TCATA extends the Check-All-That-Apply (CATA) method. Selection and deselection of attributes are tracked continuously over time, permitting assessors to characterize the evolution of...

Temporal Dominance of Sensations (TDS) involves selection and continuous update of a dominant attribute, and provides sequence data to characterize products. As a novel development in this manuscript, TDS data are represented in dominance sequences (TDS monads, TDS dyads, TDS triads, and TDS tetrads). Then, two main lines of research are followed....

The evolution of sensory characteristics during the application of cosmetic creams has been long recognized as important. However, standard methodologies do not evaluate how sensory characteristics of products change during application, and do not determine the onset of specific sensations. In this manuscript, a new temporal methodology, Temporal C...

Although Temporal Dominance of Sensations (TDS) is nowadays widely recognized as a valuable technique for assessing temporality in food perception, current analysis of TDS data could certainly be improved if the sensometrics community would become more interested in them. Furthermore, recent data (Thomas et al., 2013) suggest that TDS can be used w...

A check-all-that-apply (CATA, often also known as choose-all-that-apply) question is a question format that has been used in recent years to obtain rapid product profiles from consumers. Consumers are presented with a list of attributes and asked to indicate which words or phrases appropriately describe their experience with the sample being evalua...

The complexity of sensory data can be overwhelming to the uninitiated, particularly when considering the nature of time-related testing (Time Intensity, Temporal Dominance of Sensations, Temporal Order of Sensations, Progressive Profiling, etc.). Researchers attempt to simplify the story told by these rich data sets through graphs, but the tools cu...

Training targets were established using descriptive analysis profiles of 20 commercial red wines produced by a well-trained, experienced determination panel. After recruitment, screening and a basic sensory orientation of ten 2h common training sessions, 16 inexperienced panelists were divided by lottery into two panels. The control panel received...

The performance of descriptive panels is typically determined by post-hoc data analysis. Poor panel performance is measured after the fact and often arrives too late to help the panel leader during training sessions. The feedback calibration method (FCM) optimizes proficiency by ensuring efficient panel training. A previously trained panel (Panel T...

Training targets can be established from product profiles that provide an objective representation of the underlying sensory characteristics of a group of products. If available to a panel leader, these training targets can be used to calibrate a panel and measure the accuracy of their responses. Response accuracy can be determined either by freque...

Training targets can be established from product profiles that provide an objective representation of the underlying sensory characteristics of a group of products. If available to a panel leader, these training targets can be used to calibrate a panel and measure the accuracy of their responses. Response accuracy can be determined either by freque...

Data from a descriptive analysis panel sometimes fails to detect differences between products for one or more sensory attributes. Results might nonetheless be consistent with the best possible data; lack of discrimination could be meaningful information if no true sensory difference exists between products for the attribute, which might occur when...

Single-attribute time-intensity (TI) analysis is used to determine how a sensation changes with time for a given product or stimulus. Intensity data from a single TI panelist for one product can be represented as a curve. Although not strictly the case, a TI curve will often monotonically increase then monotonically decrease in intensity. We model...