Odor evaluation, physical, chemical

Because the quality and health aspects of foods cannot be measured by a single index, it necessarily follows that the subject of control methods in the canned food industry is very broad, and includes chemical, physical, organoleptic, and bacteriological tests, only the first of which is discussed here. The measurement of color, odor, optical clarity, texture, viscosity, and chemical composition has been used to evaluate canned foods, but in many cases the methods that are applicable to one product are either not applicable to another, or can be used only after considerable modification. 

Regardless of the official specifications for soybean oil and its products, the ultimate proof of the pudding is in the eating that is, sensory evaluation of the odors and flavors of soybean oil and its products is the ultimate method to assess oil quality and stability. Sensory evaluation cannot be replaced fully by any chemical or instrumental analysis, although some methods can correlate fairly well with sensory results. Sensory evaluation of oils usually is done by a panel of experts or a trained panel, and often the method recommended by the American Oil Chemists Society (300) is used. During the evaluation, the panel is asked to score the overall flavor quality, as well as the intensity of many individual off-fiavors. Although chemical and physical tests are more reproducible and less time consuming than sensory evaluations, oxidative rancidity and off-flavor evaluation of soybean oils are best done by sensory tests. Correlations established between sensory evaluation scores and... 

Obtaining factual information on the concentration of vapor in the air must be obtained by chemical or physical measurement only. Relying on subjective evaluation, such as odor, may be misleading. 

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