Food waste in campus dining operations: Inventory of pre- and post-consumer mass by food category, and estimation of embodied greenhouse gas emissions

Abstract

There are many economic, social and environmental reasons to reduce the occurrence of food that is wasted. As communities consider options for managing their food waste streams, an understanding of the volume, composition and variability of these streams is needed to inform the decision-making process and potentially justify the capital investments needed for separation and treatment operations. This more detailed inventory also allows for the estimation of embodied resources in food that is wasted, demonstrated herein for greenhouse gas emissions (GHGs). Pre- and post-consumer food waste was collected from four all-you-care-to-eat Campus Dining Services (CDS) facilities at the University of Missouri, Columbia over 3 months in 2014. During the study period approximately 246.3 metric tons (t) of food reached the retail level at the four facilities. 232.4 t of this food was served and 13.9 t of it (10.1 t of edible and 3.8 t of inedible), was lost as pre-consumer waste. Over the same time period, an estimated 26.4 t of post-consumer food waste was generated at these facilities, 21.2 t of the waste edible and 5.3 t of it inedible. Overall, 5.6% of food reaching the retail level was lost at the pre-consumer stage and 10.7% was lost at the post-consumer stage. Out of the food categories examined, ‘fruits and vegetables’ constituted the largest source of food waste by weight, with grains as the second largest source of food waste by weight. GHGs embodied in edible food waste were calculated. Over the study period an estimated 11.1 t CO2e (100-yr) were embodied in the pre-consumer food waste and 56.1 t were embodied in post-consumer food waste for a total of 67.2 t. The ‘meat and protein’ category represents the largest embodiment of GHG emissions in both the pre- and post-consumer categories despite ranking fourth in total weight. Beef represents the largest contribution to post-consumer GHG emissions embodied in food waste with an estimated 34.1 t CO2e. This distinction between the greatest sources of food waste by weight and the greatest sources of GHG emissions is relevant when considering alternative management options for food waste.

Enhancing anaerobic digestion of food waste through biochemical methane potential assays at different substrate: inoculum ratios

“…The food waste recipe was developed based on weekly food scrap collections at the University of Missouri campus dining operations, as outlined in Costello et al (2015). The ingredients for the food waste recipe were purchased from a local Wal-Mart food center.…”

Food Waste Management — Reducing and Managing Food Waste in Hospitality

“…Food waste generated in the hospitality sector can be divided into two categories, depending Natasa Kilibarda et al Food waste management -reducing and managing food waste in hospitality on whether it is generated before or after the food is consumed. Pre-consumer food waste occurs during the procurement and storage of purchased raw materials (storage/purchase waste), then during the food preparation (preparation waste), and food exposure (as a result of overproduction) (Baldwin, 2015;Betz et al 2015;Costello et al, 2016;Arafat, 2016, Kilibarda, 2019b). Post-consumer waste refers to leftovers on the plate itself.…”

“…Post-consumer waste refers to leftovers on the plate itself. Waste generated at this stage is also called plate food waste (Costello et al, 2016) and is defined as food purchased by a consumer and subsequently not eaten (Costello et al, 2016). Overproduction waste could also be seen as post-consumer waste since it refers to food that, although not sold to the consumer, is prepared with this intention (Costello et al 2016).…”

“…Waste generated at this stage is also called plate food waste (Costello et al, 2016) and is defined as food purchased by a consumer and subsequently not eaten (Costello et al, 2016). Overproduction waste could also be seen as post-consumer waste since it refers to food that, although not sold to the consumer, is prepared with this intention (Costello et al 2016). Food waste can also be classified depending on whether it is edible or inedible, and whether it can be prevented or not (WRAP, 2009;Parfitt et al, 2010).…”

Backcasting to identify food waste prevention and mitigation opportunities for infant feeding in maternity services

“…Studies of acute hospitals conducted by the Irish Environmental Protection Agency found that approximately 0.73 kg of food waste is generated per in-patient bed day (Environmental Protection Agency, 2013). However, akin to other studies (Costello et al, 2015), accounting for liquid foodstuffs such as fresh milk, breast-milk substitutes and fruit juices that can be poured down drains or soaked into other foods presents a significant challenge. Waste milk and breast-milk substitutes have high biological oxygen demand, are sources of nitrogen and phosphorus pollution and may cause operational issues especially to on-site waste water treatment plants where dilution factors may be lower.…”