Buying too much, preparing in abundance are top causes of food waste at home

A study published in the International Journal of Consumer Studies shows that the top causes of food waste in homes include buying too much, preparing in abundance, unwillingness to consume leftovers, and improper food storage.

For the study, in-home interviews were conducted with the mothers of lower middle class families from two suburbs of Sao Paulo, Brazil, to collect information about each family’s shopping, cooking, and disposal practices. Each family was also observed and photographed preparing, eating, and disposing of food.

Based on interviews and in-home observations, the researchers determined that the practice that resulted in the most food waste was simply buying too much food, followed by preparing food in abundance. Leaving foods on dishes after meals or not saving leftovers, and decaying of prepared foods after long or inappropriate storage were also significant factors that resulted in disposal of foods.

Furthermore, the researchers found that strategies that are intended to save money, such as buying in bulk and shopping monthly—rather than more frequently—and cooking from scratch, actually contributed to the generation of food waste and ultimately did not result in savings.

“Fortunately most of the factors that lead to food waste can be easily remedied by simple changes in food buying, preparing, and storing,” said the study’s lead author Gustavo Porpino, PhD candidate at the Getulio Vargas Foundation and visiting scholar at the Cornell Food and Brand Lab.

Empirical data for the study were collected from 14 lower-middle income Brazilian households, based on observations, in-depth interviews, photographs and a focus group (n = 6). Five major categories of food waste antecedents were identified: (1) excessive purchasing, (2) over-preparation, (3) caring for a pet, (4) avoidance of leftovers and (5) inappropriate food conservation.

Several subcategories were also found, including impulse buying, lack of planning and preference for large packages. Surprisingly, findings show that strategies used to save money – such as buying groceries in bulk, monthly shopping trips, preference for supermarkets and cooking from scratch – actually end up generating more food waste. This mitigates the savings made during the purchasing phase.

This article aims to identify antecedents of food waste among lower-middle class families – a paradox, given the financial constraints this population faces. The importance of this research is evident in escalating environmental pressures for better use of our planet’s scarce resources. Given that most of the world is low-income, any behavioral change in this population is likely to have a considerable impact.