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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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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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.

Temporal Rate-All-That-Apply (TRATA): A novel temporal method for sensory evaluation

John Castura/ August 8, 2021/ Poster/ 0 comments

This study introduces temporal rate-all-that-apply (TRATA) as a new temporal sensory method. It was inspired by rate-all-that-apply (RATA) and temporal check-all-that-apply (TCATA), but is most similar to multiple-attribute time intensity (MATI) in that the TRATA method allows for simultaneous rating of attribute intensities over time. Only attributes that are perceived are scaled. In this case study, the TRATA method was

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Do window treatments protect the acceptability for sale of red and white wine?

John Castura/ September 30, 2018/ Poster/ 0 comments

Light-struck taints in wine develop when they are exposed to sunlight and elevated temperature. Affected wines undergo a colour change, a decrease in fruit flavours and a development of off-flavours that have been described as cooked cabbage and/or corn nuts. This poses a problem in retail stores that have a large number of external facing windows that can potentially expose

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Using contrails and animated sequences to visualize uncertainty in dynamic sensory profiles obtained from temporal check-all-that-apply (TCATA) data

John Castura/ December 23, 2016/ Peer-reviewed Paper/ 0 comments

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 projected into the solution space to form contrails.