Sensory profiling experiments

Profile Fitting to a Predesigned Sensory Profile Experiment I... 

Table VII shows some hypothetical "desired" sensory profiles for these experiments, as well as the expected sensory profile one could empirically obtain, along with the combination of odorants which come as close as possible to generating that desired profile (as obtained from the multiple objective programming method). To generate these specific profiles, one often must use intermediate levels of each odorant not...

In the case of pineapples, the 12 odorants listed in Table 16.7 were dissolved in water in concentrations equal to those determined in the fruit [50]. Then the odour profile of this aroma model was evaluated by a sensory panel in comparison to fresh pineapple juice. The result was a high agreement in the two odour profiles. Fresh, fruity and pineapple-like odour notes scored almost the same intensities in the model as in the juice. Only the sweet aroma note was more intense in the model than in the original sample [50]. In further experiments, the contributions of the six odorants showing the highest OAV (Table 16.7) were evaluated by means of omission tests [9]. The results presented in Table 16.8 show that the omission of 4-hydroxy-2,5-dimethyl-3(2H)-furanone, ethyl 2-methylbutanoate or ethyl 2-methylpropanoate changed the odour so clearly that more than half of the assessors were able to perceive an odour difference between the reduced and the complete aroma model. Therefore, it was concluded that these compounds are the character-impact odorants of fresh pineapple juice. 

Preliminary GC analysis revealed that there are more number of peaks in roasted samples compared to plain cashews. Also selective extraction method was found to be slightly superior to the SDE method under the conditions of the experiment adopted in this study. However, the compounds in oven-roasted and oil-roasted samples did not differ much, qualitatively and quantitatively. In total, 26 compounds have been identified in plain cashews and 3 compounds in roasted samples. The identified peaks constituted 70 percent of the total peaks registered in GC analysis of the individual samples. The descriptive flavor profile of the eluting peaks of the plain and roasted samples were studied. Since the flavor isolate from oven roasted cashew nuts contained the flavor components of plain cashews also and since analysis showed that there was not much difference between the flavor constituents of oven-roasted and oil-roasted samples, the aromagram of the oven-roasted cashew nuts (SDE) was taken as representative. Fig.l gives the GC profile of oven roasted cashew nuts and the sensory properties of the numbered peaks are included in Table III. 

The aroma of a food product is often measured by a sensory technique called descriptive profiling, in which flavour experiences are described by a panelist as a set of component impressions or sensations of varying degrees (1). Profiles do not hold explicit information about the temporal characteristics of a flavour, its persistence and the times of appearance of the individual notes. Nevertheless, the rank order of the attributes sometimes reflects, to some extent, the order of appearance of the corresponding impressions. Some notes are then said to be released "early", others "late". 

The facet of cromolyn s activity profile on which we concentrated was the compound s reported tachyphylactic action in both the rat PCA screen and in producing a Bezold-Jarisch reflex induced fall in blood pressure in the anaesthetised dog flO. 141. In essence, a high dose of the compound administered to a rat 30 - 60 minutes before a second dose, given in the normal manner at the time of antigen challenge, inhibits or abolishes the protective effect of the latter dose on the rat PCA reaction. In the anaesthetised dog, we have found that a fifteen minute infusion of a low dose of cromolyn blocks the normal depressor activity of a subsequent bolus injection of the compound. The blocking action of the infused dose diminishes with time as shown in Figure 1. The loss of activity with time in these experiments probably reflects the rate of elimination of the cromolyn from the sensory receptors in the left ventricle of the heart which have been shown to be involved in the... 

Tables I, II, III and IV show the data base for the four sets of experiments reported there. Note that in each experiment a group of non-expert panelists evaluated each of the sets of odor mixtures twice, using magnitude estimation scaling. Thus, the tables each present numbers which are averages of approximately 32-36 ratings, depending upon the particular study. Furthermore, note that in Tables l-IV, the panelists profiled each stimulus on a variety of sensory characteristics.

The Workplace Big 5 Profile (Howard Howard, 2010), which assesses the degree to which an individual responds to stress, tolerates sensory stimulation from people and situations, is open to new experiences and new ways of doing things, pushes toward goals, and defers to others. 

In the second experiment, a consumer panel was composed of 89 naive French consumers. They were women aged from 27 to 55 years old. They all were heavy users of perfumes from the selective market, but none of them had prior experience in the sensory descriptive profiling of perfumes. 

The specificities of the automotive industry make the use of conventional profiling difficult. There are two main issues first, conventional profiling is time consuming and when cars must be rented for that purpose, the cost of a study can be astronomical second, due to the availability and the various experiences of the experts of the company, it is almost impossible to reach a consensus on sensory aspects in less than 6 months with one 3 h session a week. As the automotive company cannot manage specific sensory panels for each elanent of the car, the training and the assessments make the conventional profiling very time consuming. 

As a final conclusion, a rapid sensory method such as n is useful because it can lead to quick wins for the industry. But, even if the method is quite simple to understand, it is our opinion that the experimenter should have a solid experience in conventional profiling to obtain the best of the methodology. 

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