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From the literature on paired preference testing, there has been disagreement regarding whether a placebo pair would have a significantly higher frequency of 'no preference' responses if it were to be placed for assessment after its corresponding target pair rather than before. This can be important, because the higher the frequency of 'no preference' responses in the placebo pair, the more powerful will be any chi-squared related analysis, which determines whether the target pair indicates a significant preference or not. In the first paper in this series, it was shown, that indeed a placebo placed after the target pair induced a higher proportion of consumers to respond with a 'no preference'. However, the response was uneven. For some stimuli, the response was strong and significant, for others it was weaker and not significant. It was hypothesized that the weak response could be due to greater variance among the individual stimuli in the placebo sample to be tasted. The effect was confirmed using a priori chosen high and low variance stimuli. Further evidence was obtained from predictions for preference tau criterion levels and frequency of preference changes between two target pairs. All these indicated that the weaker response of some stimuli was due to a higher level of variance among the individual stimuli., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

One form of paired preference test protocol requires consumers to assess 2 pairs of products. One is the target pair under consideration, while the other is a putatively identical pair named the "placebo pair" which is also presented as a control. Counterintuitively, the majority of consumers report preferences when presented with the placebo pair. Their response frequencies are hypothesized to be those of consumers having "no preference" and are compared with the response frequencies elicited by a target pair, to determine whether the target pair elicits significant preferences. The primary goal of this paper was to study the robustness of 2 new so called disruptive protocols that reduced the proportion of consumers, who reported preferences when assessing a putatively identical pair of products. For this task, the tests were performed in a different language, in a different country, using different products from before. The results showed that the proportion of consumers reporting preferences for the placebo pair was reduced, confirming earlier work. Also, comparison of d' values showed a lack of significant overall differences between the placebo and target pairs, while chi-squared analyses indicated significant differences in the response frequencies. This indicated that the sample was segmented into 2 balanced groups with opposing preferences., (© 2016 Institute of Food Technologists®)

The 9-point hedonic scale has been used routinely in food science, the same way for 60 years. Now, with advances in technology, data from the scale are being used for more and more complex programs for statistical analysis and modeling. Accordingly, it is worth reconsidering the presentation protocols and the analyses associated with the scale, as well as some alternatives. How the brain generates numbers and the types of numbers it generates has relevance for the choice of measurement protocols. There are alternatives to the generally used serial monadic protocol, which can be more suitable. Traditionally, the 'words' on the 9-point hedonic scale are reassigned as 'numbers', while other '9-point hedonic scales' are purely numerical; the two are not interchangeable. Parametric statistical analysis of scaling data is examined critically and alternatives discussed. The potential of a promising alternative to scaling itself, simple ranking with a hedonic R-Index signal detection analysis, is explored in comparison with the 9-point hedonic scale., (© 2014 Society of Chemical Industry.)

Background: The present study cross-culturally investigated the drivers of liking for traditional and ethnic chicken marinades using descriptive analysis and consumer taste tests incorporating the check-all-that-apply (CATA) method. Seventy-three Koreans and 86 US consumers participated. The tested sauces comprised three tomato-based sauces, a teriyaki-based sauce and a Korean spicy seasoning-based sauce. Chicken breasts were marinated with each of the five barbecue sauces, grilled and served for evaluation. Descriptive analysis and consumer taste tests were conducted. Consumers rated the acceptance on a hedonic scale and checked the reasons for (dis)liking by the CATA method for each sauce. A general linear model, multiple factor analysis and chi-square analysis were conducted using the data., Results: The results showed that the preference orders of the samples between Koreans and US consumers were strikingly similar to each other. However, the reasons for (dis)liking the samples differed cross-culturally. The drivers of liking of two sauces sharing relatively similar sensory profiles but differing significantly in hedonic ratings were effectively delineated by reasons of (dis)liking CATA results., Conclusion: Reasons for (dis)liking CATA proved to be a powerful supporting method to understand the internal drivers of liking which can be overlooked by generic descriptive analysis., (© 2014 Society of Chemical Industry.)

In order to provide insights into why discrimination protocols with three stimuli sometimes tend to be less sensitive than protocols with two stimuli, two experiments were conducted. In these experiments, the relative effects of memory decay and memory interference were investigated. Both experiments involved purified water and/or solutions of low NaCl concentration. In Experiment 1, three protocols were compared: the traditional same-different test (Protocol 1), the same protocol with a rinse between the two samples (Protocol 2), and Protocol 2 with an added time delay between the first sample and the intermediate rinse (Protocol 3.) The decrease in measured d' values as time delay increased indicated that memory decay might be a factor for tests with three stimuli, such as the triangle method, rendering it less sensitive than tests with two stimuli, such as the same-different method. In Experiment 2, four protocols were compared: the traditional same-different test, the two-rinse same-different test, the triangle test, and what will be called duo same-different test. The experimental design allowed the individual consideration of memory decay and interference effects. From this last experiment, the substantial effect of memory interference was uncovered. Further experimentation will be necessary to estimate the exact relative effects of memory interference and memory decay.

The effect of oral capsaicin on taste sensations in humans was reinvestigated with attention to methodological issues raised in previous studies, including the mode of presentation and temperature of the tastant stimulus, as well as the sensitizing and desensitizing properties of capsaicin. One-half of the dorsal anterior tongue was pre-treated with capsaicin, followed by bilateral tastant application (sucrose, NaCl, quinine, monosodium glutamate and citric acid). Subjects indicated on which side the taste intensity was greater in a two-alternative, forced-choice procedure and also rated taste intensity independently on each side of the tongue. Each of the five tastants was tested sequentially, with reapplication of capsaicin between trials in order to maintain a constant level of burn. Four experiments were conducted: (i) a high concentration (33 p.p.m.) (109 microM) capsaicin effect on taste intensity elicited by high tastant concentrations; (ii) a high concentration capsaicin effect on taste intensity elicited by low tastant concentrations; (iii) a low concentration (1.5 p.p.m.) (4.9 microM) capsaicin effect on taste intensity elicited by low tastant concentrations; and (iv) validation of the method for localizing taste by pre-treating one side of the tongue with Gymnema sylvestre, followed by bilateral application of sucrose. In the first experiment, a significant proportion of the subjects chose the non-treated side in the two-alternative, forced-choice procedure and assigned significantly higher ratings to that side for sucrose-induced sweetness, quinine-induced bitterness and glutamate-induced umami sensations. Salty and sour sensations were not different between sides. A 15 min break was imposed in order to allow the capsaicin burn to disappear and desensitization to set in, followed by reapplication of the tastant test solutions. There were no bilateral differences in the intensity of the sensations elicited by any of the five tastants. Similar results were obtained in experiments 2 and 3. In the fourth experiment, all 15 subjects tested chose the side not treated with Gymnema sylvestre as having a stronger sweet taste and assigned significantly higher ratings to that side, thereby validating the method for taste localization. These results indicate that oral capsaicin reduces certain but not all taste sensations and are discussed in terms of possible physiological and cognitive interactions.

This article discusses the background, mechanism and need for warm-up before performing difference tests while aspects of the methodology are illustrated with examples. [ABSTRACT FROM AUTHOR]

Abstract: After experimenting with questionnaires, Odesky had recommendations for eliminating ‘No Preference’ responses in a paired preference test. He concluded that, judges who had chosen the ‘No Preference’ option would, if forced to choose, express preferences in the same pattern as those who had actually expressed a preference. Using questionnaire, food and personal product stimuli, this conclusion was found to be commonly violated. Odesky’s recommendation, to ignore or distribute ‘No Preference’ responses in the same proportion as expressed preferences was sometimes seen to distort data, sometimes not, depending on relative response frequencies and extent of violation of his conclusion regarding forced preferences. When the number of ‘No Preference’ responses is not insignificantly small, to eliminate them, runs the risk of distortion of the overall pattern of preferences. [Copyright &y& Elsevier]

Compares the everyday taste descriptions of American and Japanese subjects for a range of stimuli. Tendency to use a quadrapartite classification system in the English language; Cultural differences in taste languages; Theoretical significance to psychology.

Qualitative descriptions of low concentration sodium chloride solutions were studied using a procedure involving repetitive tasting in ascending series. Generally, subjects tended to use traditional taste categories while any new categories tended to be compounds of the old ones. However, further study suggested that at least four distinct category changes could be distinguished before salt taste recognition instead of the two traditional detection and recognition thresholds. [ABSTRACT FROM AUTHOR]

This study was conducted to understand the acceptance levels of hot sauces among consumers from different culinary cultures. Two newly developed hot sauces [fermented red chili pepper with soybean-paste-based sauce(GS) and fermented red chili-pepper-based sauce(KS)] were compared with Tabasco sauce(TB) and Sriracha sauce(SR). Two separate cross-cultural home-use tests(HUTs) were conducted: pizza and cream soup were provided as food items in HUT 1, whereas grilled chicken wings and rice noodle soup were provided in HUT 2. Consumers residing in Denmark, South Korea, and US participated in each HUT (n≅100 per country). Acceptance levels and the reasons for (dis)liking particular hot sauces applied to food systems were assessed. The food items that paired well with different hot sauces when the sauces were applied freely to regular meals were also analyzed among the US and Korean subjects. When the hot-sauce samples were applied to pizza and cream soup, the preferred order of the samples exhibited a cross-cultural agreement (GS = KS > TB). In the case of grilled chicken and rice noodle soup, the acceptance rating was similar for the three types of hot sauces among Koreans, whereas the acceptance was higher for SR among the US subjects for both foodstuffs, while Danish subjects preferred GS and KS over SR. The US subjects did not like hot-sauce samples with sweet and weak spiciness, whereas the Korean and Danish subjects disliked the hot-sauce sample when it was too spicy and not sufficiently sweet. These findings indicate that the matching of particular sauces with specific food items is culture-dependent, and this needs to be considered when trying to export food products such as hot sauce to other countries. [ABSTRACT FROM AUTHOR]

Abstract: Two experiments were performed in which untrained judges were required to perform a descriptive analysis, using a serial monadic protocol and an attribute-by-attribute protocol. They reached ‘criterion’ performance more rapidly using the attribute-by-attribute protocol, indicating that they were using a relative scaling strategy. Criterion performance required judges to rate all attributes according to the rank order of their physical strengths. Later, they reached criterion performance with the serial monadic protocol, indicating that during experimentation, they had learned to establish sufficient intensity exemplars for an absolute scaling strategy. [Copyright &y& Elsevier]

The sensation produced by carbonated beverages has been attributed to chemical excitation of nociceptors in the oral cavity via the conversion of CO[sub 2] to carbonic acid in a reaction catalyzed by carbonic anhydrase. In separate studies, we tested if the carbonic anyhdrase blocker, acetazolamide, reduced either the intensity of sensation in humans or c-fos expression by trigeminal neurons in rats, evoked by application of carbonated water to the tongue. In the psychophysical experiment, one-half of the dorsal tongue was pretreated with acetazolamide (1 or 2%), after which the tongue was exposed bilaterally to carbonated water. In a two-alternative forced-choice paradigm, subjects chose which side of the tongue yielded a stronger sensation and additionally rated the magnitude of sensation on each side. Pretreatment with acetazolamide reduced the magnitude of sensation elicited by carbonated water in a concentration-dependent manner, since a significant majority of subjects chose the untreated side of the tongue as having a stronger sensation and assigned significantly higher intensity ratings to that side. Acetazolamide did not affect the irritant sensation from citric acid, while capsaicin pretreatment reduced both the sensation elicited by carbonated water and the irritation induced by citric acid application. In a separate experiment using rats, delivery of carbonated water to the tongue significantly increased the number of cells expressing c-fos-like immunoreactivity in the dorsomedial trigeminal nucleus caudalis (versus saline controls); this was significantly reduced by pretreatment with acetazolamide. Our results support the hypothesis that carbonated water activates lingual nociceptors via conversion of CO[sub 2] to carbonic acid; the nociceptors in turn excite trigeminal neurons involved in signaling oral irritation. [ABSTRACT FROM AUTHOR]