STUDIES ON ACCEPTANCE TESTING METHODOLOGY: PRELIMINARY STUDIES ON CHARACTERISTICS OF TASTE PANEL, SAMPLE SIZE, AND CONTRAST AND CONVERGENCE EFFECTS

The report summarizes research accomplished in methodology aspects of sensory evaluation testing. Two main studies are presented in detail. The first investigated the effect of the number of samples upon differences in preference between selected samples as a function of whether they were included in the first half or second half of a series. There was no evidence that the number of samples -- varying from 2 to 12 -- had any consistent or significant effect on preference differences however, the data do suggest several hypothesis for future investigation. The second study attempted primarily to determine the effect of a fresh vs an irradiated control on preference differences, among various irradiated samples. There were logical inconsistencies in the data however, there was no basis for concluding that a fresh control attenuates the differences in preference. It appeared that quality control of the test products needed to be tightened. Research methods in this area are discussed. The report also covers the topic of sampling test subjects in-house, describes the panel population, and points out certain interrelationships among the panel members background characteristics.