Polarized Sensory Positioning Research Articles

Comparison of Sensory Profiling by Descriptive Analysis, Free-Choice Profiling, and Polarized Sensory Positioning on Bottled Water.

Consumer-oriented rapid profiling methodologies, including free-choice profiling (FCP) and polarized sensory positioning (PSP), have been studied in recent decades, highlighting alternative aspects of conventional descriptive analysis (DA). In the present study, water samples were evaluated using DA, FCP, and PSP with open-ended questions to compare the sensory profiles. Ten bottled water samples and one filtered water sample were evaluated by a trained panel for DA (n = 11), a semi-trained panel for FCP (n = 16), and naïve consumers for PSP (n = 63). The results were analyzed using principal component analysis for DA and multiple factor analysis for FCP and PSP data. The water samples were discriminated by their total mineral content, which was mainly associated with heavy mouthfeel. The overall discrimination patterns for the samples were similar between FCP and PSP, whereas DA showed different patterns. Sample discrimination through confidence ellipses from DA, FCP, and PSP showed that two consumer-oriented methodologies distinguished samples more clearly than DA. Throughout this study, consumer-oriented profiling methodologies were able to be used to investigate sensory profiles and provide rich information on consumer-derived sensory attributes even for subtly different samples.

PSP with trained assessors as alternative for descriptive analysis of a product with a complex sensory profile

Rapid sensory profiling of a product over time presents a challenge in quality control, particularly when the product has a complex aroma and flavour profile. Polarized sensory positioning (PSP), based on the comparison of samples to fixed references, allows for rapid sensory profiling and data collection across multiple sessions. The efficacy of partial and global PSP for broad-based sensory profiling of honeybush infusions, prepared from five Cyclopia species (C. genistoides, C. subternata, C. maculata, C. intermedia and C. longifolia), was investigated. Trained assessors conducted partial PSP on aroma (P-PSPa) and palate (P-PSPp), as well as global PSP. A continuous scale and five poles, representing the respective Cyclopia species, were used to evaluate the honeybush infusions. Data, aggregated over three sessions per PSP variant, were subjected to multiple factor analysis (MFA). Similar product configurations were obtained when comparing the principal component analysis (PCA) bi-plot of the descriptive sensory analysis data and the MFA plots of partial and global PSP (RV coefficients ≥ 0.87). P-PSPa was as effective as global PSP in discriminating between honeybush tea samples. Application of PSPa by trained assessors is recommended for quality control in the honeybush tea industry: in this variant of PSP assessors focus on one modality, thereby potentially reducing sensory fatigue. Cyclopia genistoides, C. longifolia and C. maculata herbal teas formed one group, indicating that these herbal teas could be blended without losing sensory character. Cyclopia subternata and C. intermedia formed separate groups, indicating their suitability for species-specific marketing.

Comparison of consumer-based methodologies for optimizing the development of new products: A case study with probiotic chocolate flavored milk.

Several studies have reported that most new products do not achieve satisfactory results when launched on the market. There is a need to increase the efficiency of the methodologies used in the development of new products to increase success rates. Rapid sensory methodologies named Polarized Sensory Positioning (PSP), Check-all-that-apply (CATA), Projective mapping (PM) or Napping were applied to obtain sensory and hedonic information of a new product, probiotic-added chocolate flavored milk, aiming at determining preference guides that can be used to obtain a high overall liking level. It was possible to develop a probiotic chocolate flavored milk with general positive overall liking. The preferred sample was formulated with high content of sugar and chocolate, concluding that these characteristics are preference guides. The results supplied by the consumers using different methodologies were consistent, although the methodologies differed in their ability for sample differentiation. CATA methodology allowed better discrimination between samples than the other methodologies, followed by Projective Mapping, PSP with scales and triadic PSP. We could confirm that those rapid methodologies of sensory characterization are efficient when applied to product development.Practical applications Using those methodologies, it was possible to develop a probiotic chocolate flavored milk that meets both, consumer's expectations in relation to nutrition and taste and functionality. The methodologies proved to be efficient in characterizing consumer preference guides, and therefore fundamental to the development of a product with higher overall liking.

SENSORY PROFILE OF BRAZILIAN COFFEES BASED ON CONSUMER PERCEPTION AS AN ALTERNATIVE TO THE CONVENTIONAL METHODS

Consumer-based methodologies for sensory characterization of foods have been widely discussed and are satisfactory, when compared to the results of trained panelists. However their efficiency in the description of complex foods rich in sensory attributes (flavor and aroma) such as coffee still needs to be explored. Polarized sensory positioning (PSP) is an innovative methodology for sensory characterization, based on the comparison of samples with reference products. In this study, roasted and ground coffees with different quality ratings according to the Coffee Quality Program (PQC) of the Brazilian Coffee Industry Association (ABIC) - Traditional, Superior and Gourmet – were evaluated by this method, applied to consumers. The beverage was presented to 100 consumers, who quantified the degree of global difference between the samples and the chosen references, using unstructured scales, followed by the verbal description of the sensory characteristics perceived in each sample evaluated. The samples were described for 30 attributes related to visual appearance, aroma, flavor, texture and hedonic terms. The method presented a good discriminative capacity, since it was able to differentiate the samples according to the PQC classification. In addition it allowed to identify the main sensory characteristics responsible for similarities and differences between the samples. The results indicate that consumers were able to infer about a quality classification based on their own perception and vocabulary, and the Brazilian traditional coffee was considered inferior to specialty coffees increasingly available in the market.

Comparison of consumer-based methodologies for sensory characterization: Case study with four sample sets of powdered drinks

Interest in consumer-based methodologies for sensory characterization has largely increased in the last decade. However, research on their applicability and reliability is still necessary. In this context, the aim of the present work was to compare three consumer-based methodologies and descriptive analysis for sensory characterization, considering as case study four sets of orange-flavoured powdered drinks, differing in the number of samples and the extent to which they represented the whole product category. A trained assessor panel evaluated sample sets using descriptive analysis, while groups of 100 consumers evaluated samples using one of three methodologies: CATA questions, projective mapping (PM) and polarized sensory positioning (PSP). Across the four sample sets, the three-consumer based methodologies provided similar information regarding the main similarities and differences among samples, which did not largely differ from that obtained using descriptive analysis. The main difference among the methodologies was related to the relative importance given to the sensory characteristics when evaluating differences among samples, which led to differences in the dimensionality of the sensory spaces. Sample configurations from PM and PSP required more dimensions than those from descriptive analysis and CATA questions to fully explain differences among samples. None of the consumer-based methodologies outperformed descriptive analysis in terms of ability to discriminate samples, being CATA questions the methodology that showed the lowest discrimination. Implications for the selection of consumer-based methodologies for specific applications are discussed.

Pole selection in Polarized Sensory Positioning: Insights from the cognitive aspects behind the task

Polarized Sensory Positioning (PSP) is a relatively new methodology for sensory characterization, based on the comparison of samples to reference products, usually called poles. The key step in the implementation of this methodology is the selection of the poles. In this context, the aim of the present work was to gain insights on the strategies used by consumers to complete this task and to study the influence of the number and characteristics of the poles on results from PSP. Three consumer studies were carried out, on three product categories: chocolate-flavored milks, vanilla milk desserts and orange-flavored powdered drinks. In each study, three groups of consumers (n=40) evaluated samples using one of three sets of two or three poles. After the PSP task consumers indicated how they evaluated the degree of difference between the samples and the poles, and listed the sensory characteristics of the poles they took into account for the evaluation. Consumers tended to evaluate the degree of difference between the samples and each of the poles by evaluating the intensity of one or two main sensory characteristics. Sample configurations obtained using two and three poles did not largely differ, especially when the poles clearly represented the sensory characteristics responsible for the main differences among samples. This work demonstrates that it is possible to unfold a multidimensional sensory space with the use of just two well-selected poles, and that the number of poles should be selected considering the main sensory characteristics that discriminate among samples.

Check-all-that-apply (CATA), sorting, and polarized sensory positioning (PSP) with astringent stimuli

Multiple rapid sensory profiling techniques have been developed as more efficient alternatives to traditional sensory descriptive analysis. Here, we compare the results of three rapid sensory profiling techniques – check-all-that-apply (CATA), sorting, and polarized sensory positioning (PSP) – using a diverse range of astringent stimuli. These rapid methods differ in their theoretical basis, implementation, and data analyses, and the relative advantages and limitations are largely unexplored. Additionally, we were interested in using these methods to compare varied astringent stimuli, as these compounds are difficult to characterize using traditional descriptive analysis due to high fatigue and potential carry-over. In the CATA experiment, subjects (n=41) were asked to rate the overall intensity of each stimulus as well as to endorse any relevant terms (from a list of 13) which characterized the sample. In the sorting experiment, subjects (n=30) assigned intensity-matched stimuli into groups 1-on-1 with the experimenter. In the PSP experiment, (n=41) subjects first sampled and took notes on three blind references (‘poles’) before rating each stimulus for its similarity to each of the 3 poles. Two-dimensional perceptual maps from correspondence analysis (CATA), multidimensional scaling (sorting), and multiple factor analysis (PSP) were remarkably similar, with normalized RV coefficients indicating significantly similar plots, regardless of method. Agglomerative hierarchical clustering of all data sets using Ward’s minimum variance as the linkage criteria showed the clusters of astringent stimuli were approximately based on the respective class of astringent agent. Based on the descriptive CATA data, it appears these differences may be due to the presence of side tastes such as bitterness and sourness, rather than astringent sub-qualities per se. Although all three methods are considered ‘rapid’, our prior experience with sorting suggests it is best performed 1:1 with the experimenter, which makes sorting relatively less efficient than CATA or PSP. Based on the evaluation criteria used here, the choice of method depends on the time constraints of the experimenter and the need for descriptive terms to understand the sensory space of the samples. Accordingly, we recommend a mixed approach that combines CATA with a subsequent PSP task so that the product space can be well characterized before choosing poles for PSP.

Evaluation of Data Aggregation in Polarized Sensory Positioning

AbstractThe aim of the present work was to evaluate data aggregation when using two polarized sensory positioning (PSP) approaches for sensory characterization with consumers. Two consumer studies with different product categories (orange‐flavored powdered drinks and chocolate milk beverages) were carried out. In each study two PSP approaches were considered: PSP with scales and triadic PSP (t‐PSP). For each approach, one‐third of the consumers evaluated the whole sample set, whereas the other two‐thirds evaluated the sample set split in two subsets. Results showed that sample configurations for the evaluation of the whole and the split set by different consumer groups were relatively well correlated (RV coefficients higher than 0.79). However, agreement between the configurations differed between the studies, which can be explained by the degree of difference among samples. Besides, differences in consumers' dissimilarity scores and conclusions regarding similarities and differences among samples were identified when comparing both data sets (with and without data aggregation). Regarding the comparison of the two PSP approaches, in the two studies better agreement between sample configurations was obtained for t‐PSP. However, in one of the studies PSP with scales provided better results for the evaluation of a repeated sample by different consumer groups.Practical ApplicationsPolarized sensory positioning has been gaining popularity in the last years. The main advantage of this methodology over other holistic methodologies is that it allows aggregating data from different studies, which is particularly interesting when working with consumer‐based sensory characterization. Results from the present work showed that aggregation of data from the evaluation of split sample sets by different consumer groups provided similar results than the evaluation of the whole sample set. However, conclusions regarding similarities and differences among samples differed in one of the studies, which suggests that care must be taken when aggregating data from the evaluation of similar samples by different consumer groups.

Polarized sensory positioning: Do conclusions depend on the poles?

Polarized sensory positioning (PSP) is a novel methodology for sensory characterization which is based on the comparison among samples and a set of reference products, called poles. Its main advantage over other holistic methodologies is that results from different sessions can be compared. This is particularly useful when working with samples with persistent flavours, when evaluating a large number of samples over a long period of time, or during quality control. Although the key step of this methodology is the selection of the products to be considered as poles, no studies have been published addressing this issue. In this context, the aim of the present work was to contribute to bridging this gap by studying the influence of the poles on results from sensory characterization of two widely different products (make-up foundations and orange-flavoured powdered drinks) using Polarized Sensory Positioning with consumers. Results from both studies provided preliminary evidence about the stability of sensory spaces obtained with different set of poles (RV coefficients higher than 0.908). However, differences in conclusions regarding similarities and differences among samples were identified between the sets of poles in both studies, suggesting the need to carefully select stable poles for PSP tasks.

Polarized Projective Mapping: Comparison with Polarized Sensory Positioning approaches

Holistic methodologies such as Projective Mapping and sorting have gained popularity for sensory characterization of products with both trained assessors and consumers. One of their main disadvantage is that all samples should be simultaneously evaluated in the same session. An alternative to overcome this limitation is to evaluate samples by comparing them with a fixed set of products, as proposed in Polarized Sensory Positioning (PSP). In the present work a combination of Projective Mapping and Polarized Sensory Positioning, called polarized Projective Mapping (PPM), is presented and compared with the two original ways of performing PSP (scale based and triadic-PSP), in terms of conclusions regarding differences between samples and difficulty for consumers. Nine orange-flavored powdered drink samples (including one blind repeated sample) were evaluated by three groups of 45 consumers using PSP, triadic-PSP and PPM using a between-subjects design. Although the three methodologies provided similar sensory spaces, some differences were identified in terms of discriminative ability, conclusions regarding similarities between samples and perceived difficulty. Polarized Projective Mapping seems to be an interesting approach that combines the advantages of Polarized Sensory Positioning and the holistic character of Projective Mapping, providing the possibility of comparing samples evaluated in different sessions.