Study: Home-delivered meal kits are greener than meals purchased at the grocery store
Pre-portioned ingredients and a streamlined supply chain lower the overall food loss and waste for meal kits compared to store-bought meals.
Meal kits have a lower overall carbon footprint than the same meals purchased at a grocery store, despite having more packaging, according to “Comparison of Life Cycle Environmental Impacts from Meal Kits and Grocery Store Meals,” a new study from University of Michigan, Ann Arbor, Mich.
Researchers found that average greenhouse gas emissions were one-third lower for meal kit dinners than the store-bought meals when every step in the process—from the farm to the landfill—was considered.
The main reason? Pre-portioned ingredients and a streamlined supply chain lower the overall food loss and waste for meal kits compared to store-bought meals.
“Meal kits are designed for minimal food waste,” says Shelie Miller, associate professor at the University of Michigan Center for Sustainable Systems in the School for Environment and Sustainability, and senior author of the study. “So, while the packaging is typically worse for meal kits, it’s not the packaging that matters most. It’s food waste and transportation logistics that cause the most important differences in the environmental impacts of these two delivery mechanisms.”
The recipes for five 2-person meals—salmon, cheeseburger, chicken, pasta and salad—were sourced and prepared from both a meal kit service and a grocery store. Meal kits were purchased from Blue Apron, New York.
Greenhouse gas emissions were estimated for every major step in the lifetime of the food ingredients and the packaging, including agricultural production, packaging production, distribution, supply chain losses, consumption and waste generation.
Greenhouse gas estimates, expressed as carbon dioxide equivalent emissions per meal (CO2e/meal), were based on values found in previously published studies.
The study found that the emissions tied to the average grocery store meal were 2 kilograms CO2e per meal higher than an equivalent meal kit. The average emissions were calculated to be 6.1 kg CO2e per meal for a meal kit and 8.1 kg CO2e per meal for a grocery store meal, a 33% difference.
Median grocery meal emissions exceeded the median meal kit emissions for four of the five meal types—salmon, chicken, pasta and salad.
Emissions differences between meal kits and store-bought meals were influenced by three main factors—food waste, packaging and the supply chain structure, which includes transportation logistics.
Emissions tied to household food waste from grocery meals exceeded those for meal kits for all five meals. The difference was attributed to meal kits pre-portioning ingredients, leaving fewer ingredients that are later wasted.
“We took a close look at the tradeoff between increased packaging and decreased food waste with meal kits, and our results are likely to be a surprise to many, since meal kits tend to get a bad environmental rap due to their packaging,” says Miller. “Even though it may seem like that pile of cardboard generated from a Blue Apron or Hello Fresh subscription is incredibly bad for the environment, that extra chicken breast bought from the grocery store that gets freezer-burned and finally gets thrown out is much worse because of all the energy and materials that had to go into producing that chicken breast in the first place.”
Meal kits and grocery meals also exhibit radically different supply chain structures that influence their greenhouse gas emissions.
By skipping brick-and-mortar retailing altogether, the direct-to-consumer meal kit model avoids the food losses that occur in grocery stores, resulting in large emissions savings. For example, grocery stores overstock food items due to the difficulty in predicting customer demand, therefore, removing blemished or unappealing foods that may not appeal to shoppers.
Meal kits also displayed emissions savings in last-mile transportation. Since each meal kit is just one of many packages delivered on a truck route, it is associated with a small fraction of the total vehicle emissions. In contrast, grocery store meals typically require a personal vehicle trip to the store and back.
In the study, last-mile emissions accounted for 11% of the average grocery meal emissions compared to 4% for meal kit dinners.
“The way consumers purchase and receive food is undergoing substantial transformation, and meal kits are likely to be part of it in some way,” says Brent Heard, who conducted the research for his doctoral dissertation. “In order to minimize overall impacts of the food system, there is a need to continue to reduce food loss and waste, while also creating advances in transportation logistics and packaging to reduce last-mile emissions and material use.”
In the study, the largest emissions source, for both meal kits and grocery store meals, was food production, with 59% of meal kit emissions and 47% of grocery meal emissions tied to agricultural production. Meals with the largest environmental impact either contained red meat or were associated with large amounts of wasted food.
The other authors are University of Michigan undergraduates Mayur Bandekar and Benjamin Vassar.