Remote testing: Sensory test during Covid-19 pandemic and beyond

Online consumer testing beyond central location tests: A case study for brewed coffee

Due to the constraints of the COVID-19 pandemic, conducting sensory evaluations requiring direct interactions became challenging. In response, researchers have been motivated to devise non-face-to-face testing methods as alternatives. This study aimed to compare two non-face-to-face home-use tests (HUT) with the traditional face-to-face central location test (CLT). Both HUTs involved online recruitment and sample delivery to participants' homes. One HUT provided a written protocol with no direct interaction (contactless HUT; C-HUT), whereas the other included an online meeting with a researcher for live guidance (online HUT; O-HUT). Four coffee samples were evaluated on the basis of liking and sensory and emotional attributes. The comparison between CLT and O-HUT showed RV coefficients of 0.92, 0.93, and 0.98 (P < 0.05) for liking and sensory and emotional attributes, respectively. In addition, based on the RV coefficient, the CLT results showed a significantly greater similarity to those of O-HUT compared to those of C-HUT. The O-HUT also outperformed the C-HUT in its ability to significantly discriminate between samples. Hence, real-time interactions between researchers and participants, as facilitated by O-HUT, may be more suitable in certain scenarios compared to C-HUT, which relies solely on a written protocol. Overall, these findings suggest that C-HUT and O-HUT are suitable methods for collecting sensory data and overcoming geographic and face-to-face contact limitations, providing greater flexibility, and reducing the time and cost associated with traditional sensory evaluations.

Remote olfactory assessment using the NIH Toolbox Odor Identification test and the brain health registry

BACKGROUND

Early identification of deficits in our ability to perceive odors is important as many normal (i.e., aging) and pathological (i.e., sinusitis, viral, neurodegeneration) processes can result in diminished olfactory function. To realistically enable population-level measurements of olfaction, validated olfaction tests must be capable of being administered outside the research laboratory and clinical setting.

AIM

The purpose of this study was to determine the feasibility of remotely testing olfactory performance using a test that was developed with funding from the National Institutes of Health as part of a ready-to-use, non-proprietary set of measurements useful for epidemiologic studies (NIH Toolbox Odor ID Test).

MATERIALS AND METHODS

Eligible participants older than 39 years and active (within 6 months) in the Brain Health Registry (BHR), an online cognitive assessment platform which connects participants with researchers, were recruited for this study. Interested participants were mailed the NIH Toolbox Odor ID Test along with instructions on accessing a website to record their responses. Data obtained from subjects who performed the test at home was compared to the normative data collected when the NIH Toolbox Odor ID Test was administered by a tester in a research setting and validated against the Smell Identification Test. The age-range and composition of the population ensured we had the ability to observe both age-related decline and gender-related deficits in olfactory ability, as shown in the experimental setting.

RESULTS

We observed that age-associated olfactory decline and gender-associated performance was comparable to performance on the administered test. Self-administration of this test showed the age-related loss in olfactory acuity, F(4, 1156)=14.564, p<.0001 as well as higher accuracy for women compared to men after controlling for participants' age, F(1, 1160) = 22.953, p <.0001. The effect size calculated as Hedge's g, was 0.41.

CONCLUSION

These results indicate that the NIH Toolbox Odor ID Test is an appropriate instrument for self-administered assessment of olfactory performance. The ability to self-administer an inexpensive olfactory test increases its utility for inclusion in longitudinal epidemiological studies and when in-person testing is not feasible.

Multi-attribute temporal descriptive methods in sensory analysis applied in food science: A systematic scoping review

Among descriptive sensory evaluation methods, temporal methods have a wide audience in food science because they make it possible to follow perception as close as possible to the moment when sensations are perceived. The aim of this work was to describe 30 years of research involving temporal methods by mapping the scientific literature using a systematic scoping review. Thus, 363 research articles found from a search in Scopus and Web of Science from 1991 to 2022 were included. The extracted data included information on the implementation of studies referring to the use of temporal methods (details related to subjects, products, descriptors, research design, data analysis, etc.), reasons why they were used and the conclusions they allowed to be drawn. Metadata analysis and critical appraisal were also carried out. A quantitative and qualitative synthesis of the results allowed the identification of trends in the way in which the methods were developed, refined, and disseminated. Overall, a large heterogeneity was noted in the way in which the temporal measurements were carried out and the results presented. Some critical research gaps in establishing the validity and reliability of temporal methods have also been identified. They were mostly related to the details of implementation of the methods (e.g., almost no justification for the number of consumers included in the studies, absence of report on panel repeatability) and data analysis (e.g., prevalence of use of exploratory data analysis, only 20% of studies using confirmatory analyses considering the dynamic nature of the data). These results suggest the need for general guidelines on how to implement the method, analyze and interpret data, and report the results. Thus, a template and checklist for reporting data and results were proposed to help increase the quality of future research.

Consumer testing away from a sensory facility: Application of home-use test and no-contact home-use test

COVID-19 pandemic-related restrictions for approximately three years have heavily influenced sensory evaluations. People have become accustomed to working remotely and communicating online. This has led to opportunities in sensory testing paired with logistics systems and information technologies, resulting in a wide application of the home-use test (HUT), wherein panelists evaluate samples from their homes or other off-site locations. This study aimed to compare three sensory evaluation conditions: a central location test (CLT, n = 104), a HUT (n = 120), and a no-contact HUT (N-HUT, n = 111). We recruited participants via the local community website, delivered samples using a delivery service, and conducted sensory testing using a smartphone for the N-HUT. Participants were requested to report the acceptance ratings, sensory profiles, and emotion responses to four coffee samples. Some differences in the acceptance ratings might be due to the different attitudes participating in the evaluation. In the sensory profiling of the samples, multi-factor analysis (MFA) revealed highly similar sensory characteristics across the three types of tests. All RV coefficients (RVs) among the test conditions were above 0.93. The emotion responses to coffee samples were similar among test conditions based on the MFA with RV values greater than 0.84. In conclusion, we found that N-HUT produced similar results regarding the descriptions of sensory profiles and emotions, indicating that N-HUT is a suitable test method for collecting sensory data and overcoming CLT and HUT's regional limitations. Modern logistics systems and information technologies make it possible to conduct nationwide sensory evaluations without in-person contact or participant attendance at sensory testing facilities.

Impacts of Utensil Conditions on Consumer Perception and Acceptance of Food Samples Evaluated under In-Home Testing during the COVID-19 Pandemic

Sensory professionals are looking for alternative ways to conduct laboratory sensory testing, especially central location testing (CLT), during the COVID-19 pandemic. One way could be conducting CLTs at home (i.e., in-home testing). It is questionable whether food samples under in-home testing should be presented in uniform utensils, as it does so under laboratory sensory testing. This study aimed to determine whether utensil conditions could affect consumer perception and acceptance of food samples evaluated under in-home testing. Sixty-eight participants (40 females and 28 males) prepared chicken-flavored ramen noodle samples and evaluated them for attribute perception and acceptance, under two utensil conditions, using either their utensils ("Personal") or uniform utensils provided ("Uniform"). Participants also rated their liking of forks/spoons, bowls, and eating environments, respectively, and attentiveness to sensory evaluation under each utensil condition. Results of the in-home testing showed that participants liked ramen noodle samples and their flavors under the "Personal" condition significantly more than under the "Uniform" condition. Ramen noodle samples evaluated under the "Uniform" condition were significantly higher in terms of saltiness than those evaluated under the "Personal" condition. Participants liked forks/spoons, bowls, and eating environments used under the "Personal" condition significantly more than those used under the "Uniform" condition. While overall likings of ramen noodle samples, evaluated under the "Personal" condition, significantly increased with an increase in hedonic ratings of forks/spoons or bowls, such significant correlations were not observed under the "Uniform" condition. In other words, providing uniform utensils (forks, spoons, and bowls) to participants in the in-home testing can reduce the influences of utensils on consumer likings of ramen noodle samples evaluated at home. In conclusion, this study suggests that sensory professionals should consider providing uniform utensils when they want to focus solely on consumer perception and acceptance of food samples by minimizing influences of environmental contexts, especially utensils, in the "in-home" testing.

Sensory Wheel and Lexicon for the Description of Cold-Pressed Hemp Seed Oil

Cold-pressed hemp seed oil (CP-HSO) has become available on the market and is gaining popularity mainly for its appeal and nutritional profile. The sensory quality largely depends on seed quality and processing as well as oil storage conditions. Given the "native" nature of the product, obtained by cold-pressing, the development of a standardized methodology to evaluate and describe the sensory quality of HSOs is of the utmost importance. To this aim, 16 commercial HSOs were evaluated, covering the main differences in brands and sales channels. A trained panel developed a vocabulary to describe the HSO profile consisting of 44 attributes, and a practical sensory wheel was proposed to classify attributes in different clusters and according to sensory modality. A sensory profile sheet was developed including two color descriptors (yellow, green), seven main positive (sunflower/pumpkin seeds, nutty, toasted nutty, hay, sweet, bitter, and pungent), several secondary positive (herbs, coffee, tobacco, etc.), four main defects (rancid, paint, burnt, and fish), and other secondary negative descriptors (boiled vegetables, cucumber, etc.). Subsequently, specific training of the panelists was carried out, and a satisfactory performance level was reached. This study represents the first attempt to standardize the sensory quality and terminology of HSO.

Effects of Test Location and Sample Number on the Liking Ratings of Almond Beverage and Vegan Ramen Products

The present study investigated the effects of the evaluation environment and sample number on liking ratings within the same testing session. It comprised two experiments that determined consumer taste ratings of the following food products: (1) almond beverage and (2) vegan ramen, as rated by 322 and 287 Korean consumers, respectively. Consumers tasted each food product under either laboratory or home-used test conditions. Additionally, three levels of sample numbers were established for evaluation (almond beverage test: 1, 2, and 4; vegan ramen test: 1, 3, and 5) in each test condition. A target sample was selected for each of the two food products to directly ascertain the effects of the evaluation environment and sample number on the liking ratings. The results revealed that during the same evaluation session, the sample number affected the liking ratings of the target sample more than the testing location. Moreover, the sample number effect was product item dependent, that is, no significant change was noted in the liking ratings of the target almond beverage sample according to sample number, whereas significant differences were observed in the liking ratings of the target vegan ramen sample. Furthermore, the sample number effect was more prominent under laboratory test conditions than under home-used test conditions probably due to the serving order effect driven by hedonic contrast, carry over effect, and sensory specific satiety. The findings demonstrate that home-used tests should be recommended over laboratory tests when measuring the liking of a small number of multiple sample food items with high flavor complexity.

Effects of COVID-19 on sensory and cognitive perception of mild and severe diagnosed and recovered patients versus healthy consumers

The objective of this research was to analyze the effects of the SARS-CoV-2 virus on the sensory and cognitive perception of mild and severe COVID-19 diagnosed and recovered consumers versus healthy consumers. Three groups of 50 consumers each (healthy vs. mild and severe COVID-19 diagnosed with 30 days after recovery) were used for the evaluation of instant coffee stimuli in concentrations: 4.40, 2.93, 2.20, 1.76, and 1.47% weight (w)/volume (v) and determine their discriminating power, emotions, and memories. Sensory tests were performed remotely. Results indicated that healthy consumers perceived higher intensities in most of the sensory attributes (with the exception of Burnt-A, Bitter-T, Acid-T, and Astringent-T attributes) compared to consumers who presented mild and severe COVID-19. Therefore, consumers diagnosed with mild and severe COVID-19 had a higher discrimination power in the attributes smell, basic tastes, and flavor. Healthy consumers could only discriminate two attributes that correspond to basic flavors. Consumers with mild and severe COVID-19 diagnosis elicited the highest number of negatives emotions (such as bored, disgusted, worried, guilty, wild, and aggressive) and negative memories (disease, pain, death, hurt, obesity, conflict personal, addiction, stench poverty, and accident) than healthy consumers. It is concluded that there were no significant differences between the consumer panels for the identification of sensory attributes. However, P-Healthy consumers perceived the highest intensities in most sensory attributes compared to those in the PCOVID19-Mild and PCOVID19-Severe panels. Finally, consumers diagnosed with mild or severe COVID-19 used a higher number of emotions and memories than those of the healthy panel.

Practical applications

Investigating the effects of COVID-19 on sensory and cognitive perception can be useful for industry and researchers in the sensory field who wish to understand the effects of the disease in order to generate new protocols for the selection and training of people, as well as the possible development and innovation of new products focused on perception of consumers recovered from COVID-19.

Remote sensory assessment of beer quality based on visual perception of foamability and biometrics compared to standard emotional responses from affective images

The social isolation settings derived from the COVID-19 pandemic affected the standard sensory evaluation techniques used in the food and beverage industry. This situation forced companies and researchers to assess other options to continue conducting these tests in remote contactless locations. This study aimed to evaluate two sets of samples (i) six images from Geneva affective picture database (GAPED) and (ii) six videos of beer pouring using traditional self-reported sensory data and emotional response from consumers biometrics. Specifically, four research questions (RQ) arouse from this study: RQ1: are there significant differences between GAPED images and beers in unconscious and self-reported responses from consumers?, RQ2: are there any correlations between subconscious and self-reported responses from consumers when assessing beer?, RQ3: can consumers differentiate positive, neutral and negative images based on subconscious and self-reported responses?, RQ4: are there any relationships between subconscious and self-reported responses when assessing GAPED images and beers, and how are samples associated with variables? A total of 113 Mexican beer consumers participated in the virtual sensory session using an online videoconference software to record videos of participants during the session. Results showed there were significant differences (p < 0.05) between samples, especially for self-reported responses (RQ1), and several correlations between variables, such as positive correlations between the perceived quality of beers and happy emoji (r = 0.84), and negative correlation with confused emoji (r = -0.97; RQ2). Besides, using the proposed methods, consumers were able to correctly differentiate through elicited emotions the positive, neutral and negative GAPED images (RQ3). Regarding RQ4, several relationships were found between variables in both GAPED images and beers; however, it was found that different emotions were elicited depending of the stimuli used. The proposed method showed to be a reliable and practical option to conduct visual and potentially tasting sensory tests in isolation and recruit participants from different countries without travelling to collect their responses.

Characterizing Individual Differences in Sweet Taste Hedonics: Test Methods, Locations, and Stimuli

Sweetness drives the consumption of added sugars, so understanding how to best measure sweet hedonics is important for developing strategies to lower sugar intake. However, methods to assess hedonic response to sweetness vary, making results across studies difficult to integrate. We compared methods to measure optimal sucrose concentration in 21 healthy adults (1) using paired-comparison preference tracking vs. ratings of liking, (2) with participants in the laboratory vs. at home, and (3) using aqueous solutions vs. vanilla milk. Tests were replicated on separate days to assess test-retest reliability. Test-retest reliability was similar between laboratory and home testing, but tended to be better for vanilla milk and preference tracking. Optimal sucrose concentration was virtually identical between laboratory and home, slightly lower when estimated via preference tracking, and about 50% lower in vanilla milk. However, optimal sucrose concentration correlated strongly between methods, locations, and stimuli. More than 50% of the variability in optimal sucrose concentration could be attributed to consistent differences among individuals, while much less variability was attributable to differences between methods. These results demonstrate convergent validity between methods, support testing at home, and suggest that aqueous solutions can be useful proxies for some commonly consumed beverages for measuring individual differences.

Sensory Panel Performance Evaluation—Comprehensive Review of Practical Approaches

Sensory assessors determine the result of sensory analysis; therefore, investigation of panel performance is inevitable to obtain well-established results. In the last few decades, numerous publications examine the performance of both panelists and panels. The initial point of any panelist measures are the applied selection methods, which are chosen according to the purpose (general suitability or product-specific skills). A practical overview is given on the available solutions, methods, protocols and software relating to all major panelist and panel measure indices (agreement, discrimination, repeatability, reproducibility and scale usage), with special focus on the utilized statistical methods. The novel approach of the presented methods is multi-faceted, concerning time factor (measuring performance at a given moment or over a period), the level of integration in the sensory testing procedure and the target of the measurements (panelist versus panel). The present paper supports the choice of the performance parameter and its related statistical procedure. Available software platforms, their accessibility (open-source status) and their functions are thoroughly analyzed concerning panelist or whole panel evaluation. The applied sensory test method strongly defines the applicable performance evaluation tools; therefore, these aspects are also discussed. A special field is related to proficiency testing. With the focus on special activities (product competitions, expert panels, food and horticultural goods), practical examples are given. In our research, special attention was given to sensory activity in companies and product experts or product-specific panels. Emerging future trends in this field will involve meta-analyses, application of AI and integration of psychophysics.