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Figure 6. Illustration of a saddle formation, response surface analysis. The vertical axis shows degree of maltiness imparted to tea on addition of varying amounts of epicatechin (abscissa) and l-penten-3-ol (ordinate).

to another. Dijksterhuis (32) has explained the principles and techniques underlying GPA. GPA has especial application when consumers are allowed to use "free-choice profiling" to describe their perceptions of the qualities of a set of foods (33,34). Trained panelists are normally asked to rate the intensities of an established set of terms. There are good reasons for not training consumers to use a re stricted set of terms. In free-choice profiling, the panelists are free to use whatever terms seem appropriate to them to describe the sensations they are perceiving. A consequence is that the configuration of terms and intensities applied to the sensation almost always differ for each panelist. GPA involves rescaling of the intensity values and rotation of the configurations to bring them as closely as possible into alignment with each other. The investigator thereby secures a consensus configuration of the terms and of the relationships of the products to each other. The process derives its name from the mythical innkeeper Procrustes, who made all his guests exactly fit the beds. If the guest were longer than the bed, Procrustes cut off the guest's legs at the appropriate place, if the guest were smaller than the bed, Procrustes used a rack to stretch the unwary guest. Kaye (35) commented that "in a procrustean approach to a theory, the scientist stretches and pulverizes any data until it [they] fits the preconceived ideas." That is not a valid criticism applied to free-choice profiling. The investigator might have a preconceived notion as to the pattern of the consensus configuration, but free-choice profiling hardly favors much in the way of a firm idea of the pattern to be evolved. Others, in only two publications that will be cited (36,37), have commented upon or reported comparisons between GPA and other multivariate forms of analysis.

Homemade Pet Food Secrets

Homemade Pet Food Secrets

It is a well known fact that homemade food is always a healthier option for pets when compared to the market packed food. The increasing hazards to the health of the pets have made pet owners stick to containment of commercial pet food. The basic fundamentals of health for human beings are applicable for pets also.

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