A procedure for validating the use of photographs as surrogates for samples in sensory measurement of appearance: An example with color of cooked turkey patties

Abstract

AbstractAssessing visual characteristics of products can be difficult as they can change over time, vary in natural products, and be perceived differently due to factors such as lighting. This study examines the use of photographs, which can be problematic if they show color shifting in different lighting conditions, as a substitute for freshly prepared products and compares the photographs with samples under different lighting conditions. Three replicates of ground turkey patties cooked to six different end point temperatures that provided various shades of pink, brown, and gray were used for this study. Photographs of the samples were compared to freshly prepared samples under simulated daylight conditions by a highly trained descriptive sensory panel in a balanced randomized order. Eighteen photographs verified as matching the samples (three for each of six samples) in “daylight” subsequently were compared under consumer lighting conditions: incandescent, halogen, Compact Fluorescent (CFL), Light Emitting Diode (LED), and daylight LED bulbs. Each photograph was found to match freshly prepared samples under each of the different lighting conditions as well. This study shows that photographs can potentially be used as visual references for products, and that they behave similarly to freshly prepared samples under different lighting conditions.Practical applicationsThis study suggests that photographs can be used in place of actual products with proper validation of the photographs. In addition, this study provides one procedure for validating photographs against actual products that can be used in other research studies.