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In immersive VR, a self-avatar that replicates the user’s movements and is viewed from a first-person perspective can substitute the real body. If the avatar’s movements are sufficiently synchronized with the user’s actual movements, the user can experience a sense of embodiment over the avatar. Recent studies have shown that discrepancies between the movements of the avatar and those of the user can be well tolerated while maintaining high levels of embodiment. The point at which a distortion is perceived (detection threshold) and its impact on the level of embodiment has not been studied in lower limb tasks such as gait. This study aimed to identify a detection threshold of gait asymmetry by unilaterally manipulating the step length of a self-avatar, and the effect of this detection on perceived embodiment. A real-time step length distortion model was developed, and a detection threshold between actual and avatar’s gait movement was assessed on thirty healthy participants. The step length was manipulated to introduce gait asymmetry (ascending condition) or start from a large asymmetry that was gradually decreased (descending). The results showed that, on average, the avatar’s step length could be increased by up to 12% before the participants detected the distortion. Furthermore, in the descending condition, they detected increases that were above 9%. The point of detection had no effect on the sense of embodiment as participants still reported being embodied in their avatars, even when they consciously detected the step length distortion. The sense of embodiment was closely correlated with the level of distortion; as distortion increased, embodiment decreased, and vice versa. For a given distortion level, embodiment was similar whether in the ascending or descending condition. This suggests that embodiment can be achieved even when the avatar’s spatial alignment initially differs from the participants’, provided that alignment is gradually restored. These results provide valuable insights into participants’ ability to tolerate movement discrepancies in embodied avatar experiences during gait in virtual environments, with potential applications in motor training and gait rehabilitation. [ABSTRACT FROM AUTHOR]

Freshness is an important quality attribute for vegetables. Identifying the sensory drivers for freshness is important to promote vegetable consumption. Due to the lack of research on freshness of prepared vegetables, this study focused on the role of visual cues of common vegetables (carrot, beetroot, bell pepper) on perception of freshness. Twenty-seven vegetables were prepared by varying five factors and photographed in a plate: (1) shape (stick, large cube, small cube), (2) vegetable presence for each of the three vegetables (yes, no), (3) number of vegetables conjointly present in the plate (1, 2, 3), (4) color (green bell pepper, yellow bell pepper), (5) combined vegetables prepared with same or different shapes. Freshness was rated online by 156 consumers. Visual cues leading to the main increase in freshness were the stick shape vs. large and small cubes, the absence of beetroot, and the presence of green bell pepper vs. yellow bell pepper. Overall, it seems that visual cues associated with minimally processed vegetables, such as stick shapes, which allow to recognize the vegetables in comparison to cube shapes, promote freshness. These results are particularly valuable for culinary and catering professionals and food industries involved in the preparation and/or manufacturing of prepared vegetables. [ABSTRACT FROM AUTHOR]

A robust and reproducible model was developed to predict the sensory profile of espresso coffee from instrumental headspace data. The model is derived from 11 different espresso coffees and validated using 8 additional espressos. The input of the model consists of (i) sensory profiles from a trained panel and (ii) on-line protontransfer reaction mass spectrometry (PTR-MS) data. The experimental PTR-MS conditions were designed to simulate those for the sensory evaluation. Sixteen characteristic ion traces in the headspace were quantified by PTR-MS, requiring only 2 min of headspace measurement per espresso. The correlation is based on a knowledge-based standardization and normalization of both datasets that selectively extracts differences in the quality of samples, while reducing the impact of variations on the overall intensity of coffees. This work represents a significant progress in terms of correlation of sensory with instrumental results exemplified on coffee.