A choice experiment for different preparation methods of eggs: The impact of sensory, health, and animal welfare

• A discrete choice experiment examines the impact of different ways of eating eggs on its attributes in Japan. • Attributes are yolk color, omega-3, sterilization, animal welfare, and locality. • Consumer preferences vary significantly depending on how the eggs are cooked. • As the degree of heating decreased, the WTP for the sterilization becomes higher. • As the degree of rawness increases, the WTP of antibiotic-free feed rises. This study investigated the effect of cooking methods on the willingness to pay (WTP) for the sterilization method. The choice experiment consisted of eight attributes; yolk color (yellow vs. deep yellow), grade (special vs. first grade), omega-3 (3 levels), egg sterilization method (no sterilization vs. sodium hypochlorite vs. pasteurization), hen feed (antibiotics vs. antibiotic-free vs. organic), hen’s breeding method (caged vs. cage-free), production area (in-prefecture vs. out of prefecture), and price (5 levels). The online survey included 1,000 Japanese consumers. A within-subject design was employed in which everyone responded under the assumptions of eating a hard-boiled egg, a soft-boiled egg, and a raw egg. As the degree of heating decreased, the WTP for the sterilization attribute became higher. Sodium hypochlorite was always higher than pasteurization. As the degree of rawness increased, the WTP for antibiotic-free and organic feeds rose. However, the organic feed had a lower WTP than the antibiotic-free feed. When eating raw eggs, the WTP for antibiotic-free was the second most important compared with the sterilization. As the degree of rawness increased, the WTP for the deep yellow color of the yolk rose, and finally reached three times higher when eating raw eggs than when eating hard-boiled eggs. The WTP for local production was not significantly different in any case. Omega-3 had a significant negative WTP only for raw eggs. Cage-free had a significant negative WTP only for boiled eggs.