Sensory evaluation, use

When comparing the dust-borne concentrations of butyric acid and p-cresol with the odour thresholds it seems that the concentrations are too small to be relevant for an odour nuisance. However, if the dust is removed from the gas phase of the air from animal houses the odour disappears (39), (40), (14). This supports the opinion of HAMMOND et al. (40) that the odor is concentrated on the dust particles. The authors conclude from their data that the concentration of the two odorants butyric acid and p-cresol is about 4TO7 greater on an aerosol particle than it is in an equal volume of air. Thus, an aerosol particle deposited on the olfactory organ carries odour equivalent to a much greater volume of air (40). These considerations indicate that dust from animal houses should be taken into account in connection with odour emission/immission measurements not only by chemical analysis but by sensory evaluations using olfactometers without dustfilters, as well. 

Enantioselective gas chromatography can provide three quite different kinds of information (1) the amount of each enantiomer present in a food, determined as the enantiomeric purity or the enantiomer excess, and the separation factor a for each pair of enantiomers (2) enantiospecific sensory evaluation using gas chromatography-olfactometry (GC-O) and (3) data used as part of an authenticity determination. 

Sensory assessment is a scientific discipline used to evoke, measure, analyze, and interpret responses to those properties of a substance (food or beverage) that are perceived by the five human senses sight, smell, taste, touch, and hearing. Even though individual judgments are subjective, the techniques of sensory evaluation use objective scientific testing methods principally based on working with a panel of assessors. Two types of analytical objective tests can be observed (1) The discriminative tests is there a difference between several products (2) The... 

From Man and Jaswir (2000). Frying of potato slices carried out at 180°C. Sensory evaluations used a hedonic scale of 1 = dislike extremely, to 7 = like extremely. 

The choice of an emollient for a skin care formulation is mostly based on sensorial evaluation using well-trained panels. These sensorial attributes are classified into several categories ease of spreading, skin feeling directly after application and 10 minutes later, soffness, etc. A lubricity test is also conducted to establish a friction factor. Spreading of an emollient may also be evaluated by measurement of the spreading coefficient (see Chapter 11). 

To predict the comfort of a material, a combination of hand evaluation, eg, using the Kawabata system, as well as deterrnination of the heat and moisture transport properties, is necessary. Often, these values are correlated with a sensory evaluation of the tactile qualities of the material by a human subject panel. A thorough discussion of the many physical and psychological factors affecting comfort is available (134,135). 

Three attributes characterize color hue, lighmess (or value), and saturation (or chroma) and they are graphically represented in color solids (e.g., Munsell solid. Hunter solid). The Munsell Color Notation is a rapid, portable, widespread, and economical system of color determination. However, as it depends on sensory evaluation by panels, many laboratories prefer when possible to replace human judgment by instrumental techniques that are easier to handle. The CIELAB established by the Commission International d Eclairage (CIE) has become widely used with the availability of reflectance spectrophotometric instrumentation. 

Using these rhelogical methods laboratories for quality control and research and development have good tools to characterize pectins in gels and solutions. The most important points are the reproducable handling, pretreatment, and measurement of the samples and the knowledge which information can be derived from the measured data regarding the texture, the production parameters, and the sensory evaluation of the product. 

The data from sensory evaluation and texture profile analysis of the jellies made with amidated pectin and sunflower pectin were subjected to Principal component analysis (PC) using the statistical software based on Jacobi method (Univac, 1973). The results of PC analysis are shown in figure 7. The plane of two principal components (F1,F2) explain 89,75 % of the variance contained in the original data. The attributes related with textural evaluation are highly correlated with the first principal component (Had.=0.95, Spr.=0.97, Che.=0.98, Gum.=0.95, Coe=0.98, HS=0.82 and SP=-0.93). As it could be expected, spreadability increases along the negative side of the axis unlike other textural parameters. 

The purpose of preparative-scale liquid chromatography is the isolation of materials conforming to a specified purity in cUBOunts that depend on the intended use of the product [8,570-572]. Possible uses Include the isolation of materials for structural elucidation, for biological or sensory evaluation, for organic synthesis or commercial applications. The scale of the... 

During the CEC-seminar in Bad Zwischenahn, Kowalewsky (1) concluded that NH3 is suitable for use as a main component. He defined a main component as a compound whose concentration correlates with the sensory evaluation of odour intensity. 

A forced-choice detection method should be used to reduce the influence of variables that are inherent to sensory evaluation, such as anticipation, decision criteria, doubt and adaption, etc. 

On the basis of a sensory evaluation, the air in cowsheds using peat was slightly fresher than that in the other cowsheds. The same result was obtained in the farm interviews. 

SugawaraY, Kara C, Tamura K, FujiiT, Nakamura K, MasujimaT, AokiT, Sedative effect on humans of inhalation of essential oil offinalool Sensory evaluation and physiological measurements using optically active finalools, Anal Chim Acta 365 293-299, 1998. 

Suprathreshold particle suspensions were evaluated using Magnitude Estimation (ME) and Sensory Descriptive Analysis (Carrasco and Siebert,... 

Sensory evaluation of cooked potato quality is based on appearance and mouthfeel scored by trained or untrained evaluators using some form of hedonic scale on which the assessor records the perceived value of the attribute, typically on a nine-point scale, from extreme like to extreme dislike. 

Knowing the relationships between chemical and sensorial variables, objective methods can be obtained to evaluate the food quality. Juries of experts cannot be formed and used so easily as the measurement of chemical quantities can. Besides, the knowledge of these relationships will be able to retain, so to speak, sensorial evaluations and follow the evolution of taste over a long period, so that it may be foreseen as well. 

In the past few decades, a precise methodology has been developed for sensory evaluation and has proved to give reliable results [826]. Increasingly, in recent years chemical sensor systems ( electronic noses ) are used for such purposes [826a]. 

Sensory evaluation is carried out by the use of sensory organs and most importantly by the nose. It is considered crucial for the acceptance of an essential oil in perfumery houses. A perfumer or a panel of fragrance experts often have the last word on the acceptance criteria however, their assessment should be verified and documented by experimental proof [1, 2, 4, 5, 69-73]. 

We chose a general view because the impact of computers on flavor and fragrance research is not limited to a particular area. The advent of the microprocessor has made powerful, inexpensive microcomputers available to the analytical chemist and the sensory scientist alike. These people have connected them to their machines, used them to control robots, and placed them in their sensory evaluation booths. The successful development of inexpensive memory and very fast central processing units, on the other hand, has made very powerful minicomputers available to the computational chemist and the information scientist. These researchers now routinely use the computer to design new functional molecules, design new products, and keep track of huge collections of molecules and associated data. 

The second area of progressive development will be in the area of very specialized data collection mediums. We foresee a major extension in the area of direct data input using interactive video terminals built within the sensory evaluation booths. Although this will take a fairly extensive development in the area of software, the gains to be reaped by the development will far exceed the development costs itself. A large area of research has yet to be conducted concerning the application of microcomputers in sensory analysis as a data collection tool. Studies of inherent bias, effects on response freedom etc. will have to be undertaken in order to properly evaluate the computer as a data acquisition tool. Biases based on the way the software... 

We also feel there is room for extensive testing and research in new areas associated with this type of technology. For example, time dependent measurements may be important for various types of sensory evaluation. Previously, to achieve time dependent measurements was a tremendously exhaustive chore and may not have been able to be made using normal taste panel procedures and environments. With this type of application of microcomputers in sensory evaluation we foresee the use of time dependent measurements as a new area of possible development. 

Sensory Evaluation. Results on the sensory evaluation of the three encapsulated powders showed that all three powders developed oxidized flavor even at first sampling time (3 days). Since an expert trained panel was used, the recognition threshold of members for oxidized flavor was far below the expected value. In addition, since oven stored samples were evaluated against freezer stored samples in the pair comparison test, panelists could not characterize the degree of difference in oxidized flavor between various powders. It is therefore suggested that lower storage... 

---