Spectrum Descriptive Analysis Research Articles

Predicting tactile sensory attributes of personal care emulsions based on instrumental characterizations: A review.

Emulsions in the form of creams, lotions, gels or foams are the most widely used personal care formulations to improve the condition and feel of the skin. Achieving an optimal balance between their performance, effectiveness and sensory profile is essential, with the sensory profile being a key factor in consumer satisfaction and the success of these products in the market. Well-established methods using highly trained and semi-trained panels (e.g. Spectrum descriptive analysis, Flash Profile method, Quantitative Descriptive Analysis method and 'Check-all-that-apply') are available and commonly used for the sensory assessment of personal care products. Nevertheless, a common drawback among all these methods is their inherent cost, both in terms of financial resources and time requirements. In recent years, research studies have emerged to address this limitation by investigating potential correlations between tactile sensory attributes and instrumental data associated with the physical characteristics of topical formulations. In other words, significant efforts have been invested in the development of robust instrumental methods specifically designed to accurately predict the sensory description that a panel of assessors could establish. These methods are not only faster, cheaper and more objective compared to traditional sensory testing, but they can also be applied to formulations that have not undergone extensive safety and toxicological testing. This review summarizes the most relevant findings, trends and current challenges in predicting tactile sensory attributes of personal care emulsions based on instrumental parameters.

Predicting textural attributes and frictional characteristics of topical formulations based on non-linear rheology

A number of analytical procedures (Spectrum Descriptive Analysis (SDA), Quantitative Descriptive Analysis (QDA), and Check All That Apply (CATA)) are used for characterizing sensorial attributes of topical formulations. However, these techniques are evaluated by expert panels/consumers, which are subjective, expensive and time consuming. Despite widespread use of these methods, the techniques do not necessarily aid in the development of innovative formulations and understanding of consumer liking. In addition, the hedonic attributes of a product can significantly dominate the sensation. Therefore, a more rapid, quantitative, and objective approach is required for understanding the formulation factors that governs sensory perception at different points of consumer application. Rheological evaluations of topical formulations were carried out under steady and oscillatory (SAOS and LAOS) rheology using a commercial rheometer. Friction measurements were performed using an in-house built tribometer on non-biological skin model to investigate how surface properties are influenced by application of different topical formulations. Further, a broad range of instrumental texture measurements was performed to characterize the formulations. Principal component analysis was used for dimensionality reduction of the instrumental data. Supervised machine learning was performed on the closely related PCA parameters to develop predictive models. We identified physical parameters relevant to different perceptual attributes by comparing a range of commercial topical formulations with various compositions using rheological and tribological methods. Multi-variate machine learning models were developed where several key instrumental textural attributes and skin feel could be predicted from data obtained from linear and non-linear rheological measurements. Our study shows rheological analysis based on a few material parameters can be effectively used for predicting instrumental sensory attributes that is of relevance to consumer care industry. The machine learning models may benefit development of innovative formulations, valorisation of new materials and serve as a platform for mapping commercial formulations for product optimization. The models can likely shorten design cycle time by screening through large volume of formulations and short list only those with highest potential to be evaluated by a very specialized and expensive human test panel.

An overview of bitter compounds in foodstuffs: Classifications, evaluation methods for sensory contribution, separation and identification techniques, and mechanism of bitter taste transduction.

The bitter taste is generally considered an undesirable sensory attribute. However, bitter-tasting compounds can significantly affect the overall flavor of many foods and beverages and endow them with various beneficial effects on human health. To better understand the relationship between chemical structure and bitterness, this paper has summarized the bitter compounds in foodstuffs and classified them based on the basic skeletons. Only those bitter compounds that are confirmed by human sensory evaluation have been included in this paper. To develop food products that satisfy consumer preferences, correctly ranking the key bitter compounds in foodstuffs according to their contributions to the overall bitterness intensity is the precondition. Generally, three methods were applied to screen out the key bitter compounds in foods and beverages and evaluate their sensory contributions, including dose-over-threshold factors, taste dilution analysis, and spectrum descriptive analysis method. This paper has discussed in detail the mechanisms and applications of these three methods. Typical procedures for separating and identifying the main bitter compounds in foodstuffs have also been summarized. Additionally, the activation of human bitter taste receptors (TAS2Rs) and the mechanisms of bitter taste transduction are outlined. Ultimately, a conclusion has been drawn to highlight the current problems and propose potential directions for further research.

Tactile friction and rheological studies to objectify sensory properties of topical formulations

The aim of the work was to identify the physical parameters relevant to different perceptual attributes by comparing a range of commercial skin creams with various compositions. We investigated the possibility of predicting sensory properties using rheological and tribological methods. Rheological evaluations of the skin creams were carried out using continuous shear, creep, creep recovery, rheodestruction and recovery measurements, oscillatory strain sweep measurements [small amplitude oscillatory shear (SAOS) and large amplitude oscillatory shear (LAOS)], and frequency sweep measurements. Friction measurements were performed on the nonbiological skin model to investigate how surface properties are influenced by the application of different topical formulations. Furthermore, the formulations were characterized by a broad range of instrumental texture measurements. In vivo sensory analysis based on the spectrum descriptive analysis method was performed to discriminate the skin creams during pickup, rub out, and after feel. Using principal component analysis meaningful correlation relating rheotribological properties and sensory attributes during the entire process of product application was carried out. Rheological parameters deduced from the nonlinear regime were found to be important parameters affecting the frictional response of skin creams. In addition, friction data were correlated with slipperiness and stickiness—subjective attributes used for the sensory evaluation of after feel. Furthermore, a number of key textural parameters and sensorial data showed good correlation with results obtained from linear and nonlinear rheological measurement, indicating rheological analysis can be sufficiently used as a precise and valid tool for sensorial mapping of topical formulations. Our study further suggests that objective evaluation based on the flow curve, oscillatory strain sweep (SAOS and LAOS), and friction measurements can be used for sensorial screening of large number of prototype formulations, which otherwise may be time consuming and costly using a sensory panel.

Sensory optimisation of lemongrass (Cymbopogon citratus) and pandan (Pandanus amarylifolius Roxb.) herbal tea on several brewing techniques

Conservatively, tea is an aromatic beverage made from dried leaves of tea plant (Camellia sinensis). However, lemongrass (Cymbopogon citratus) and pandan leaves (Pandanus amarylifolius Roxb.) can also be processed as herbal tea to develop their functional properties. This current study aims to investigate the sensory profiles of the herbal tea as well as to determine the optimum techniques for hot, iced and hot+ice brewings. Spectrum Descriptive Analysis method was conducted by involving 12 trained panellists to develop sensory vocabularies. Meanwhile, the sensory optimization was conducted by Just about Right (JAR) method involving 106 consumer respondents. The Spectrum data shows that 4 out of 12 sensory attributes, including sweet, astringency, lemongrass flavor, and pandan flavor; were significantly affected by different brewing techniques (p-values <0.05). Through Penalty analysis on JAR data, it shows that sweet and pandan flavor were optimum for hot brewing. Meanwhile, the sweet and astringency were optimum for cold brewing. Under current set up, there is no optimum attributes was obtained for hot+ice brew technique. Considering their functional properties, the cold brewed herbal tea shows the most superior among the samples tested as it shows the highest total sugar content, total phenolic compound, and antioxidant activity (p-values<0.05).

How does composition influence the texture of cosmetic emulsions?

Using the Spectrum Descriptive Analysis method, the present work defines a methodology developed in order to discriminate and characterize cosmetic oil-in-water emulsions as well as their respective aqueous phases containing xanthan gum. The objective was to describe and understand how composition parameters govern texture perception, through the study of the impact of the amount of (1) xanthan and (2) oil phase. For that purpose, emulsions were developed by varying either their amount of xanthan or oil concentration. Seven texture attributes were selected and defined using precise and strict evaluation protocols and notation scales to set up a quantitative framework: integrity of shape, penetration force, wetness, ease of spreading, grease, stickiness and gloss. Results demonstrate the contribution of each parameter to the texture of emulsions and aqueous phases. For example, increasing the oil phase ratio in emulsion mainly enhances the consistency, grease degree and residual stickiness of the creams. Moreover, the study establishes consistent linear relationships according to the concentration in xanthan in solutions for five attributes: integrity of shape, penetration force, wetness, ease of spreading and gloss. Interestingly, the effect of xanthan in emulsions is similar but obviously diminished when compared to polymer solutions.

Development of a Sensory Lexicon for Dairy Protein Hydrolysates

AbstractThe objective of this study was to develop a sensory lexicon for dairy protein hydrolysates (DPHs) produced from whey and casein substrates. To create the lexicon, 25 DPHs were assessed by a trained sensory panel (n = 8) using the spectrum descriptive analysis method using a 15‐point intensity scale. The sensory panel identified over 43 attributes present in the DPHs, the attributes that occurred the most frequently formed the refined lexicon of 19 attributes, which were then scaled by their intensity. Principal component analysis was employed to visualize the relationships between attributes and samples. The DPHs were separated by their attributes as whey protein hydrolysates were found to have a more complex flavor profile than casein hydrolysates, which were found to be bitter, astringent and metallic. The attribute that was found to clearly characterize the DPH samples was bitterness as the taste occurred in all samples and many of which were of high intensity.Practical ApplicationsDairy protein hydrolysates (DPHs) are a variety of food ingredient that is of interest to the food industry for their functionality within foods, their nutritional profile and their bioactivity. However, it has been reported in previous studies that DPHs can have undesirable sensory attributes. This sensory lexicon was created to allow for a more systematic and quantitative approach to characterizing sensory attributes of DPH. Such information would be valuable to manufacturers contemplating on the use of DPH as ingredients in foods, allowing the evaluation of the impact of DPH on product sensory properties as well as helping to direct any masking strategies required. While lexicons for whey‐based DPHs have been published, this work represents the first attempt to develop a combined lexicon for DPH based on either whey or casein. The principal component analysis based on descriptor scores shows clear differences between the sensory attributes of whey protein and casein‐based DPHs.

Ranked-Scaling: A new descriptive panel approach for rating small differences when using anchored intensity scales

Some descriptive analysis methods use established and constant references to scale attribute intensities, where the scale represents the intensity range across a variety of products. As a result, when evaluating samples from the same food category, the observed intensity range for many attributes fall within a narrow portion of the scale. This compressed range can limit the ability to differentiate subtle differences among samples. Published approaches to relative rating techniques position/re-position samples relative to each other on a scale, relative to the full range of the scale, or relative to a reference item. Unique to Ranked-Scaling is the positioning of samples relative to intensity references.A descriptive panel, trained and experienced in the Spectrum Descriptive Analysis Method, was provided a set of 3–6 products, a list of 3–5 attributes, and standard intensity references appropriate to those attributes. For each attribute, panelists were asked to first rank the samples in order of intensity (re-tasting was permitted), then assign intensity values using the standard scale. The ability of the panelists to significantly differentiate small differences in attribute intensity and to correctly order subtle intensity differences more often with the Ranked-Scaling procedure has been demonstrated for both flavor and texture, and across product categories. The ability to show significant trends among samples tightly grouped on the anchored intensity scale has provided more meaningful guidance to product developers, while maintaining the ability to compare to product profiles from the standard methodology across projects and time.

Impact of Polymers on Texture Properties of Cosmetic Emulsions: A Methodological Approach

AbstractA methodology, particularly well adapted to the evaluation of cosmetic creams containing various texturing agents, is defined here using the Spectrum Descriptive Analysis method. The objectives were to describe and to understand the contributions of the texturing agents to the texture attributes of oil‐in‐water emulsions. The study focused on eight hydrophilic polymers, either natural (e.g., xanthan), semi‐synthetic (e.g., hydroxypropyl guar) or synthetic (e.g., carbomer), incorporated each one in an o/w emulsion. Eight texture attributes were selected and precisely defined, with strict evaluation procedures and notation scales. These attributes were gloss, integrity of shape, penetration and compression forces, stringiness, difficulty of spreading, absorbency and stickiness. A quantitative frame of reference was also developed. The methodology accuracy was evaluated through statistical analysis thus proving the sensory panel was highly discriminative, reproducible and repetitive. Principal component analysis underlined that polymers conferred to creams a very different skin feel when compared to the “control” emulsion without polymer. Synthetic polymers were characterized by higher consistency and lower gloss; semi‐synthetic polymers and xanthan by higher degrees of stringiness, whereas carob exhibited intermediate properties.Practical ApplicationsThis study may concern all the actors of the cosmetic industry, either the marketing, the quality control or the research and development departments. The developed methodology with precise definitions, strict and reproducible protocols, and with a frame of reference will be an accurate and useful tool to improve or optimize sensory evaluations of cosmetic creams, especially to investigate all the sensory aspects conferred to products by texturing agents. In the present study, the eight polymers were chosen as frequently used in cosmetic applications. As a consequence, both the methodology and the results are precious tools for product development and product optimization in order to meet consumers' texture quality requirements.

THE DEVELOPMENT OF A LEXICON FOR FROZEN VEGETABLE SOYBEANS (EDAMAME)

ABSTRACT American vegetable soybean (edamame) consumption is limited, but potential for increased markets based on U.S. production is high. Vegetable soybeans (Glycine max.[L.] Merrill) are harvested while the seeds are still immature. Because of limited harvesting time, freezing is essential for year‐round availability of edamame. A lexicon to identify and define the aromatics, tastes and feeling factors for edamame was created using a total of 20 shelled and in‐pod samples of commercial frozen edamame. The edamame lexicon development was initiated by a commercial sensory company, further developed by a 12‐member panel of flavor and/or soybean specialists and finalized by a trained sensory panel. Intensity ratings, based on the Spectrum descriptive analysis method, were assigned to terms in the lexicon. References that exemplified the terms were obtained and evaluated for applicability by the panel. Edamame flavor was described by 13 aromatic attributes, three feeling factors and the basic tastes that were subsequently used by a trained descriptive panel to demonstrate the usefulness of the terms and intensities on a subset of the original commercial samples and limited samples from a blanching study using freshly harvested vegetable soybeans.

TERMINOLOGY DEVELOPMENT AND PANEL TRAINING FOR SENSORY EVALUATION OF SKIN CARE PRODUCTS INCLUDING AQUA CREAM

ABSTRACT This article describes the approach of the spectrum descriptive analysis (SDA) method to evaluate sensory properties of skin care products. The terminology for various lotions and creams was developed using SDA. A total of 26 attributes on five phases was developed with definitions and scales. Through discriminative, descriptive and scaling testing, 10 panelists were selected, and panel training was conducted until the panel grand standard deviation of the evaluated data of calibration samples showed less than 1.0. After the extensive training on sensory perceptions and scaling, the panelists evaluated the 26 attributes on 12 aqua‐cream products. In the principal component analysis result of aqua‐cream data, the first principal component (PC) was mainly related to oiliness, viscosity, adhesiveness and thickness on one side of the scale and transparency, wetness, coolness and spreadability on the other, with 40% of variance. The stickiness and gloss contributed greatly to the second PC with 30% of variance. The total amount of variance that was explained at the two PCs was 78%. In the biplot loadings of products and attributes, creams of K and L were identified by their higher degrees of wetness, spreadability and moisturization. They had lower degrees of stickiness, gloss and oiliness.

Context Effects in Evaluation of Chocolate Quality Through the Experimental Design–Cross-Cultural Study

ABSTRACT The aim of this study was twofold. First, to find out whether there are any differences in sensory sensitivity of Belgian and Polish panelists evaluating plain chocolate products. Second, to investigate the influence of quality and quantity of cocoa mass on perception of sensory attributes. Starting from the identical procedure of screening and training, panelists were selected in two-stage process. Later on, they were subjected to 6 training sessions using reference samples. Spectrum Descriptive Analysis was developed to describe intensities of sensory attributes. Finally, the panelists evaluated all chocolate products that were manufactured according to the experimental design. The central point sample, which represented the medium values of cocoa components, appeared in all tasting sessions (high-, medium- and low-intensity contexts). Data analysis was carried out in four stages. At first, all individual panelists were assessed due to the two-way analysis of variance for all sensory attributes...

DEVELOPMENT OF TERMINOLOGY TO DESCRIBE THE HANDFEEL PROPERTIES OF PAPER AND FABRICS

ABSTRACT.Understanding the tactile feel of paper, nonwoven, and woven products requires a valid and reliable sensory evaluation method which discriminates and describes handfeel properties. The Handfeel Spectrum Descriptive Analysis method separates the sensory tactile properties of paper and fabrics into clearly defined characteristics that are based on sound physical properties. The benefit of using a trained descriptive sensory panel is that resulting analytical sensory data allow full documentation of a sample's sensory tactile properties that can be related to consumer responses and instrumental physical tests. This benefit derives from strict protocols for manipulation and the use of precisely defined terms to discriminate and describe the qualitative properties (characteristics) and their relative intensities (strength) in each product. This paper discusses in detail the protocols for (1) sample preparation, presentation, and handling during evaluation, (2) the definition and scale range for each sensory attribute/characteristic and (3) the application of these data to address business and technical situations with consumer products.