Impact of consumption frequency on generations of sensory product profiles using CATA questions: Case studies with two drink categories.

Check-All-That-Apply (CATA) is a very popular tool for rapid sensory profiling in consumer research. Yet, consumers' dietary habits, such as consumption frequency, has been neglected in regard to the impact, if any, on CATA question responses. The present work aimed to fill this gap, by focusing on the effect of different consumption frequencies with four studies (N = 686). Two categories of drink products were involved, chrysanthemum tea and instant coffee. For each category, two sets of products were prepared to constitute two levels of difference between samples (larger vs. smaller). Consumers were classified into high- and low-consumption groups according to their consumption frequencies of each focal product; the size of these subgroups ranged from 54 to 130. Overall, the two groups did not produce large discrepancies from each other when constructing sensory profiling of the tested samples with CATA questions as well as the stability of sample configurations. However, there were some nuances between them. In the evaluation of chrysanthemum tea samples, the higher-consumption group of consumers presented better discrimination than the lower-consumption group while this was reversed for coffee samples. This might be mainly attributed to the fact infrequent consumers were more sensitive to such negative attributes as "strong chrysanthemum smell for chrysanthemum samples, earthy for coffee samples". Further, despite the higher stability obtained with larger sizes of difference between samples in Studies 3 and 4, in general, the effect of size of differences within sample sets was not significant between different consumption groups. To more effectively contribute to refinement of methodological guidelines for CATA questions, more validation work is needed.

Sensory product characterisations based on check-all-that-apply questions: Further insights on how the static (CATA) and dynamic (TCATA) approaches perform.

Check-all-that-apply (CATA) questions have become one of the most popular methods for sensory characterisation with consumers. Temporal CATA (TCATA) is an extension of the former that takes into account the dynamic nature of sensory perception. The aim of the present work was to expand the methodological comparison of CATA and TCATA questions, considering the characterisation of solid products that undergo substantial oral processing when consumed. Five studies involving a total of 731 consumers were conducted with different product categories: dried apricots, peas, cheese, bread and milk chocolate. A between-subjects experimental design was used to compare the static and dynamic versions of CATA questions. For comparison purposes, TCATA data were analysed as CATA by collapsing the data into four fixed time intervals (quarters). The four quarters of TCATA were compared to results from CATA considering the frequency of use of the terms, sample discrimination, and product configurations. The temporal aspect of TCATA did not largely modify the average citation proportion of terms or the maximum citation proportion for individual terms. Significant differences among samples were established for most of the terms in both CATA and TCATA evaluations, albeit some subtle differences between the two methods were found. These differences were dependent on the product category and the specific sensory characteristics that were relevant for describing the focal samples. The largest differences were found for Study 5 (milk chocolate), for which TCATA identified a few additional insights on the evolution of similarities and differences among samples. However, in most cases general findings were virtually identical for both methodological approaches. In light of these results, the extra effort of using a dynamic sensory characterisation method compared to a static one, may, in many instances, not be warranted.

Product involvement and consumer food-elicited emotional associations: Insights from emoji questionnaires.

Individual differences in food-related consumer behaviour are well documented, but lack thorough exploration in relation to product-elicited emotional associations. In this research, focus is directed to product involvement as a factor that modulates emotional associations to tasted products (dried fruit, n = 4) and written descriptions of consumption situations (drinking red wine, cooking dinner using seafood). Emoji questionnaires were used (as check-all-that-apply questions: CATA), and across two studies with consumers in New Zealand (n = 352) and China (n = 450), higher levels of involvement were associated with more positive emotional associations. For example, consumers with higher involvement for dried fruit used emoji with positive meanings (e.g., face savouring delicious food (), smiling face with heart-shaped eyes () and smiling face with smiling eyes () more frequently than those with lower levels of involvement. Conversely, emoji with negative or neutral meanings (e.g., confused face (), confounded face (), neutral face ()), were more frequently used by consumers with lower levels of product involvement. The number of significant differences between the samples of dried fruit were lower in the less involved consumer segment, and these consumers, on average, used less emoji to characterise the samples. A similar pattern of results were established for the written stimuli, which were used with Chinese consumers. For example, in the segment with greater involvement with seafood, associations to emoji with positive meanings were higher when responding to the situation "cooking dinner using frozen seafood as one of the ingredients." In the case of "drinking French red wine," the strategy used to define segments (median vs. triadic split of summed involvement scores) additionally influenced the results, and bigger differences were established when comparing more discrete segments (two extreme groups following triadic split).

Observation of ultralong valley lifetime in WSe2/MoS2 heterostructures.

The valley degree of freedom in two-dimensional (2D) crystals recently emerged as a novel information carrier in addition to spin and charge. The intrinsic valley lifetime in 2D transition metal dichalcogenides (TMD) is expected to be markedly long due to the unique spin-valley locking behavior, where the intervalley scattering of the electron simultaneously requires a large momentum transfer to the opposite valley and a flip of the electron spin. However, the experimentally observed valley lifetime in 2D TMDs has been limited to tens of nanoseconds thus far. We report efficient generation of microsecond-long-lived valley polarization in WSe2/MoS2 heterostructures by exploiting the ultrafast charge transfer processes in the heterostructure that efficiently creates resident holes in the WSe2 layer. These valley-polarized holes exhibit near-unity valley polarization and ultralong valley lifetime: We observe a valley-polarized hole population lifetime of more than 1 µs and a valley depolarization lifetime (that is, intervalley scattering lifetime) of more than 40 µs at 10 K. The near-perfect generation of valley-polarized holes in TMD heterostructures, combined with ultralong valley lifetime, which is orders of magnitude longer than previous results, opens up new opportunities for novel valleytronics and spintronics applications.