Food packaging plays an important role in attracting consumers' attention and generating expectations in the consumer that in turn affect their product perception and buying behaviour. In the present study, ‘categorizing’ and ‘perceptual mapping’—diametrically opposed methods (predefined criteria vs consumer criteria)—were used to study the influence of packaging design on consumer perceptions of dairy products. Eighty‐nine images of milk, yoghurt and yoghurt drink with different graphical designs, sizes, shapes and materials were presented to the participants. The participants were randomly divided in two groups, each of which evaluated the samples using one method: categorizing or perceptual mapping. Both categorizing and perceptual mapping have been demonstrated to be useful, simple and user‐friendly methods to determine the packaging design cues that influence the perception of dairy products. However, perceptual mapping provided more subconscious perceptions than the categorizing task. The results of perceptual mapping are objective and provide representative information. Furthermore, it fosters better understanding of the potential for product packaging to be misinterpreted and supports packaging designers in developing packages that better align with consumer perception. Copyright © 2012 John Wiley & Sons, Ltd.