Effect of consumer's decisions on acrylamide exposure during the preparation of French fries. Part 2: Color analysis

Abstract

Two observational tests were designed to investigate the influence of consumer decisions during the preparation of French fries from fresh potatoes on acrylamide formation. In both tests, color was of paramount importance to volunteers with regards to the decision to stop the frying process. CIE-Lab* color parameters and visual color assessments of French fries were associated with general acrylamide content and its classification according to the EU benchmark levels (BL, 500 μg/kg). Binary logistic regression analysis revealed that color parameter a* was the main factor in determining the probability of acrylamide content being above BL, regardless of the culinary practices applied. A cut-off of 0.855 for a* produced the greatest sensitivity (81.1%) and specificity (99.9%) for classifying samples with acceptable BL of acrylamide content. An increase of one unit of a* more than quadruple the risk of acrylamide content not falling within BL. When no external color reference was provided, volunteers misclassified 33.6% of fries as having a golden color. Harmonized criteria based on a reference color chart that indicates a golden color are necessary for producing fries with reduced acrylamide contents and, in this way, limit the risk of exposure to acrylamide in domestic settings.

Keywords: Acrylamide; Color; Consumer's decisions; French fries; Logistic regression; Visual assessment.