THE PSYCHOPHYSICAL RELATIONSHIP BETWEEN COLOR AND SALT CONCENTRATIONS IN CHICKEN FLAVORED BROTHS

Taste panelists evaluated the effect of color on salt perception in chicken flavored samples using magnitude estimation. Samples were colored to simulate commercial chicken broth. Five color intensities were added to 5 NaCl concentrations ranging from 0.34 to 0.66% (w/v). Color had no influence on salt perception. Panelists were able to perceive color differences among samples (P <0.001) and these were correlated with the objective color function cot⁻¹ (a/b) calculated from the L,a,b values obtained from the Gardner XL-23. Overall flavor preference was evaluated by a taste panel using the technique of magnitude estimation. NaCl concentrations ranged from 0.52 to 0.80% (w/v). Overall flavor preference was unaffected by color. A reduction in NaCl concentration from 0.80% (w/v) to 0.52% (a 35% reduction) did not alter flavor preference. A 50 member consumer panel using a paired comparison test found no difference in flavor preference between an uncolored sample containing 0.80% (w/v) NaCl and a colored sample containing 0.72% (w/v) NaCl.     

A STUDY OF TEXTURE-FLAVOR INTERACTIONS USING FREE-CHOICE PROFILING

Interactions between perceptions of texture and volatile flavors were assessed by free-choice profiling using gelatin desserts as a model product. Gels were prepared with all combinations of 2 levels of gelatin, and 2 concentrations of 2 different flavors. A trained sensory panel profiled each sample for aroma, flavor, and oral and manual texture. Generalized Procrustes Analysis was carried out separately for each sensory modality. The results indicate that while gelatin concentration and flavor type both modified perception of flavor, flavor concentration did not. Gelatin content influenced instrumental, oral, and manual evaluations of texture; however, the type and level of flavoring had little influence on oral perception of texture.     

THE USE OF FOURIER ANALYSIS TO COMPARE THE SENSORY PROFILES OF PRODUCTS

A consumer panel comprising 60 females evaluated three coffee whiteners and fresh milk for a number of sensory attributes including liking of flavor and appearance, overall liking, natural flavor and odor, creaminess and watery flavor. Fourier analysis was used to produce a plot which readily identified the whiteners with sensory profiles most similar to fresh milk. More importantly, the whitener whose sensory profile was significantly different from that of fresh milk was identified from the Fourier plot, something which could not be done by traditional univariate methods or even by an overall discriminant analysis.     

DEVELOPMENT OF A LEXICON FOR THE DESCRIPTION OF PEANUT FLAVOR

A lexicon of terms to describe desirable as well as undesirable flavors in peanuts has been developed. The lexicon and an intensity rating scale was developed by a 13 member panel of flavor and peanut specialists representing industry and the USDA-Agricultural Research Service. This system is intended to provide definitive, common terminology for use in communicating differences in peanut flavor variables among all phases of peanut research and industry.     

COMPARISON OF DISCRIMINATION ABILITY BETWEEN A PANEL OF BLIND ASSESSORS AND A PANEL OF SIGHTED ASSESSORS

The objective of this work was to compare a panel of blind assessors with one of sighted assessors in the discrimination of food products. Each panel had 20 screened and trained assessors. Five commercial food products were used: crackers, liver paste, powdered orange juice mix, Reggiano cheese and yogurt. Slight flavor and/or texture modifications were introduced for adequate discrimination difficulty. Each pair of products was tested by both panels using the triangle test and a scaled difference from control test. Numbers of correct answers for the triangle test were similar for both panels. There were minor differences between the panels in the difference from control test, due to the sighted panel having more training in the use of the scale. Overall the panels of trained blind and sighted assessors were equivalent in their performance.     

COMPARISON OF ATTRIBUTE LIKING AND JAR SCALES TO EVALUATE THE ADEQUACY OF SENSORY ATTRIBUTES OF MILK DESSERTS

Just-about-right (JAR) scales and attribute liking questions are usually used to study consumer perception of the sensory characteristics of food products. The aim of the present work was to compare the performance of attribute liking and JAR scales to evaluate consumers' perceived adequacy of flavor and texture of milk puddings. Two groups of consumers were asked to evaluate eight milk desserts using (1) overall liking followed by attribute liking for texture and flavor and (2) overall liking followed by JAR scales for thickness, creaminess, sweetness and vanilla flavor. Overall liking scores were significantly different when JAR scales or attribute liking questions were considered. Texture, flavor and overall liking scores were highly correlated to each other, providing the same information. JAR scales correlated better with the intensity of sensory attributes evaluated by a trained sensory panel, being JAR percentages a reliable tool to study the adequacy of sensory attributes.

PRACTICAL APPLICATIONS

Results from the present work showed that consumers might not be able to independently evaluate their liking of different sensory attributes of a product. For this reason, the use of attribute liking questions for studying the adequacy of sensory attributes in complex products would not be recommended. JAR scales were better indicators of the adequacy of sensory attributes. Consumers were able to independently evaluate texture and flavor attributes using JAR scales. However, the influence of JAR scales on overall liking scores should be taken into account when including these scales on consumer studies.     

THE RELATIONSHIP BETWEEN CONSUMER PREFERENCES AND TRAINED PANEL RESPONSES

Eight samples of dried tomato soups were profiled by a trained panel, who also provided ratings of overall liking and liking for particular attributes on relative-to-ideal rating scales. A consumer panel tested a subset of four of the soups in home trials, assessing them for overall liking and for particular attributes on either hedonic or relative-to-ideal rating scales. The pattern of overall preferences differed between the trained and untrained panelists, demonstrating the inappropriateness of using trained panelists to provide measures of preference or acceptance. The conclusions regarding consumer preferences would differ depending on which rating scale was used; these differences disappeared when the relative-to-ideal ratings were converted into values of the same form as the hedonic ratings. The overall liking was best predicted by flavor rather than color or thickness. A principal components analysis (PCA) of the profile data compared well with a plot based on the trained panel preference data using MDPREF. The preference data were also fitted to the PCA dimensions using the PREMAP vector model, which gave a good fit for only six of the 15 trained panelists; the PREMAP ideal point model failed to show a better fit. In order to test these models adequately more than eight samples would need to be tested.     

SELECTION AND SCREENING OF A DESCRIPTIVE PANEL FOR EWES MILK CHEESE SENSORY PROFILING

The aim of this work was to select a competent sensory panel considering its ability to describe ewes milk cheese sensory properties. The panelists evaluated the sensory characteristics of several ewes milk cheeses in terms of odor, flavor and texture. The performance of judges was assessed taking into account the following aspects: (1) individual discriminatory ability and reproducibility for each sensory attribute; (2) group discriminatory ability and reproducibility and agreement between judges for each attribute; (3) panel homogeneity; (4) panel consonance; and (5) overall panel discriminatory ability. The panel performance was checked with a set of statistical procedures. The results obtained by the selected group were better than the initial panel from the point of view of discriminant power, reproducibility and agreement. The suggested method can be easily applied in routine control of assessors performance and to discover deviant behavior or differences in individual perception of the samples.