Two data analysis procedures were employed in this study. First, one-way analysis of variance (ANOVA) was applied to each of the material data sets (e.g., corn flakes) to determine whether a source of uncertainty (Fig. 1, e.g., day to day changes) was statistically significant, at p = 0.05. If the targeted source of uncertainty was determined to be significant then the second procedure was applied to the material data set, uncertainty analysis. Uncertainty analysis provides a quantitative estimate of the contribution of each source of uncertainty to the combined standard uncertainty. However, if a source of uncertainty was determined not to be significant, uncertainty analysis was not carried out on that source of uncertainty. Combining ANOVA with uncertainty analysis provides both a test of statistical significance and a means of estimating the portion of the combined standard uncertainty that can be attributed to each significant source of uncertainty. The one-way ANOVA was carried using the data analysis tools in Microsoft Excel 2004 for the Mac (version 11.3.6). The details of the uncertainty analysis are provided