Investigating control-centred results after uncentred principal component analysis

John Castura/ March 23, 2025/ Preprint/ 0 comments

In sensory evaluation, principal component analysis (PCA) is often used to explore differences between products. In some studies, there is one control product (e.g. a reference or benchmark) and many test products, where test-control paired differences are of primary interest. We discovered there are two equivalent ways to investigate these results using PCA. The first approach is a centred PCA

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Comparison of Gins Using Temporal Dominance of Sensations (TDS), Temporal Check‐All‐That‐Apply (TCATA), and Temporal Ranking (TR)

John Castura/ March 17, 2025/ Peer-reviewed Paper/ 0 comments

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 temporal profile of six gins (standardized to 30%

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One citation, one vote! A new approach for analysing check-all-that-apply (CATA) data in sensometrics, using L1 norm methods

John Castura/ February 25, 2025/ Preprint/ 0 comments

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 term, leads to analyses based on the

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Investigating relationships in sensory and instrumental data using component-based methods

John Castura/ October 3, 2024/ Oral Presentation/ 0 comments

This talk focuses on new ways for investigating sensory-instrumental data relationships using component-based methods. The proposed approaches are related to manuscripts that are in preparation at the time of this abstract submission. The proposed methods could be used in a wide range of studies, but the talk will emphasize studies involving one reference treatment and many test treatments, which is

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Comparison of gins using temporal dominance of sensations (TDS), temporal check-all-that-apply (TCATA), and temporal ranking (TR)

John Castura/ October 2, 2024/ Poster/ 0 comments

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 for comparing temporal 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 temporal profile of six gins (standardized to

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Investigating test-control paired differences in flavour-molecular correlations

John Castura/ September 25, 2024/ Oral Presentation/ 0 comments

We investigate supervised principal component regression (SPCR) its sensory and instrumental results from a data set of eight pinot noir wines. Data include measured concentrations of volatile organic compounds from headspace—solid phase micro-extraction—gas chromatography—mass spectrometry (HS-SPME-GC-MS) and sensory descriptive analysis results on two selected sensory attributes evaluated orthonasally. We show the solution from SPCR as conducted conventionally is equivalent to

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Introduction to component-based methods in sensory evaluation

John Castura/ September 8, 2024/ Tutorial/ 0 comments

This tutorial surveys some of the most frequently used methods for exploring multivariate data sets fromsensory and consumer science. Component-based methods are often applied for data reduction andvisualization of results.The tutorial is divided into three parts.In Part 1, we contrast principal component analysis (PCA) with principal variable analysis, then discussmultiple factor analysis (MFA), which is often used to investigate multiblock

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Investigating sensory-instrumental relationships in a subset of test-control paired comparisons by partial least squares regression

John Castura/ September 5, 2024/ Oral Presentation/ 0 comments

Relationships between sensory and instrumental variables are often investigated using partial least squares regression (PLSR). We describe the conventional PLSR solution. Next, we describe two new approaches for conducting PLSR based on paired comparisons of objects. First, we describe the PLSR of all paired comparisons. Conducting PLSR of all paired comparisons is equivalent to the conventional solution in the sense

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Sugar replacement in chocolate-flavored milk: Differences in liking of sweetener system relates to temporal perception

John Castura/ July 31, 2024/ Peer-reviewed Paper/ 0 comments

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 treatments were formulated, varying in sucrose replacement level (partial: 58%; complete: 100%) and

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Investigating control-centred results after uncentred principal component analysis

John Castura/ June 14, 2024/ Oral Presentation/ 0 comments

Test-control paired comparisons can be investigated after principal component analysis (PCA). We show that a centred PCA of test-control paired comparisons is equivalent to an uncentred PCA of control-centred results. We demonstrate how to conduct these analyses. We illustrate key properties of centred and uncentred PCA. We justify why coordinates of control-centred results can be visualized in principal components obtained

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