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Free listing can help understand how a domain is perceived across a group of people by examining the average psychological saliency of items, in this case, menus elicited by a population. The objectives of the present work were: (a) compare different indexes used to analyze the saliency of items listed by individuals in a free-listing exercise, (b) test if time distance can be an improvement over rank distance in associating items mentioned by subjects, and (c) apply the above indexes and associations to gain insight in the menus listed by different income-level populations in Argentina. In the present study we surveyed a total of 200 women from low and medium/high-income levels who were asked to list all the menus they knew registering the mention order and time to mention. Smith’s saliency index and cognitive salience index (CSI), previously not applied in the food science literature, proved useful in selecting the core menus listed by a population. The hypothesis that time distance would be a more adequate measure of the association of items in a list than order of mention was not sustained in the present study. Cluster analysis was also found useful in analyzing how menus were grouped by different income levels using a free-listing procedure. ANOVA on the CSI values showed a significant menu × income-level interaction, thus indicating that saliency was not the same for listed menus across income levels.

The objective of the present work was to use simulation studies to estimate the number of consumers necessary to obtain valid estimations from survival analysis calculations where each consumer evaluates a single sample. Based on previous studies a Weibull model was assumed for the lifetime distribution with a shape parameter σ between 0.17 and 0.71. Simulations were calculated supposing shelf-life values in the middle range of an adimensional time scale. Graphs to estimate N under different scenarios are presented. Considering the average σ , an alpha value (Type I error) of 5%, a beta value (Type II error) of 20%, the shelf-life to be in the middle of the studied time range and a difference between the true shelf-life and the estimated shelf-life of 0.5 on a 0–6 time scale, gave an N value of 300 consumers for this particular set of parameters. As 6 time values were considered this means 50 consumers for each one of the storage times. In the present study time was taken as the reference variable, however the same calculations and conclusions are valid for other variables of interest, such as concentration or temperature, that replace the time variable in survival analysis calculations.

A total of 306 consumers from Argentina, Spain and the USA, segmented by age groups (young and middle-aged adults) and stated preference for degree of doneness (rare, medium, well-done) looked at pictures from the American Meat Science Association (AMSA) Color Guide and decided if these were under-cooked, ok or over-cooked. Survival analysis statistics were applied to the data to predict optimum internal cooking temperatures. These ±95% confidence intervals were: 75 ± 6.2 °C, 78 ± 4.3 °C and 82 ± 2.6 °C, for consumers stating a preference for rare, medium and well-done beef, respectively. Country of residence and age group had little influence on optimum temperatures. Relatively high optimum temperatures, and the fact that only 4% of the consumers found the “55 °C-very rare” and “60 °C-rare” pictures ok, suggests the necessity of revising the range of the AMSA Color Guide.