Discard intentions are lower for milk presented in containers without date labels

Eighty-eight regular milk drinkers were presented whole fat pasteurized cow's milk stored at 4 degrees Celsius in plastic containers for 15, 25, 30 and 40 days after commercial bottling. Subjects opened and smelled individual half-gallon containers presented in two flights of four that were identical except one flight featured a sell-by label with a date set to 18 days post-bottling, while the other flight lacked label dates and related language. 48.9% of respondents indicated they would discard milk featuring a date label if it were in their home refrigerator while 38.1% indicated the same for milk lacking date labels, which equates to a 28% increase in discard intention attributable to the presence of a date label. Among containers with milk 25, 30 and 40 days post bottling, 64.0% of respondents intended to discard milk in containers with date labels while 45.8% intended to discard milk in containers without such labels, which is a 40% increase in discard intentions for milk that is putatively 'past date' among commercial bottlers. Multivariate analysis reveals that discard intentions are lower among participants with higher incomes and fewer household members, but revealed no other significant correlations with personal or household characteristics. Given that the date labeling on pasteurized milk is not designed to address safety concerns, and given the high level of consumer milk waste in many developed countries, these results suggest further innovation in milk labeling may support improved sustainability by reducing the discard rate of milk attributable to sell-by date labels.