Gamithri Gayana Karunasena

Since the United Nations announced their Sustainable Development Goal 12.3 to halve per capita food waste by 2030, prevention has become an international focus. Consumers are responsible for a significant portion of food waste, and much of this waste is avoidable by improving food management routines and planning in the household. There is a growing body of research focused on developing and evaluating domestic behaviour change interventions which can improve these behaviours. However, evidence of intervention efficacy on a household level is inconsistent, and best-practice approaches for researchers, policymakers, and practitioners have not been identified. Furthermore, the magnitude of this problem across environmental, social, and economical aspects of life necessitates meaningful long-term change. Many reviews have synthesised household food waste intervention studies, yet there is a gap exploring whether new habits can or will stick. We identify 16 peer-reviewed articles applying behaviour change interventions in the household, with a pre–post design to measure food waste both before and after implementation. The review reveals a paucity of studies that evaluate intervention efficacy relative to their baseline, as well as a significant longitudinal evidence gap. Our recommendation for further research is for the robust replication of effective short-term interventions to be tested longitudinally. Overall, this review outlines potential areas for prioritisation to enable large-scale sustained household behaviour changes in the fight against food waste.

Dealing with the wicked problem of global food waste and loss is a complex and challenging area. In Australia, increased political will has landed the diversion of domestic food waste from landfill squarely at the feet of local government (councils), often requiring significant change to kerbside collections systems. This paper discusses how post-kerbside household food waste treatment systems can encourage pro-environmental behaviours. To achieve this, current food waste literature is examined against kerbside domestic waste collection measurable outcomes (diversion rates, system uptake and contamination rates). The hypothesis is that specific interventions can establish, or rebuild, community trust, responsibility and pro-environmental behaviours around food waste avoidance and diversion. Two post-kerbside systems—commercial composting and anaerobic digestion—provided the framework. Two themes emerged from the study: (1) the benefits of connecting the community with the interactions of household food waste inputs with post-treatment outputs (compost, soil conditioners, digestates and biogases); and (2) providing engaged communities with pathways for sustainable, pro-environmental actions whilst normalizing correct kerbside food waste recycling for the less engaged (habitual behaviours, knowledge and cooperation). The paper contributes to understanding how councils can connect their communities with the issues of household food waste.

Household food waste measurement tools and practices vary considerably, and therefore, it is difficult to compare studies. An accurate measurement of food waste is pivotal to achieve national food waste reduction targets. Yet only a handful of studies have attempted to compare disparate household food measurement methods. This paper uses a large, national-scale dataset (n = 2885) to compare three commonly used food waste measurement methods: self-reported survey, self-reported electronic diary and a physical waste compositional analysis or bin audit. It quantifies the degree of underestimation between the selected methods. The findings indicate that both self-reported methods, survey and electronic diary underestimate household food waste in comparison to bin audit. The degree of underestimation between the electronic diary and bin audit ranged from 7% - 16%. The findings highlight the importance of paying attention to disposal routes included in the measurement and discrepancies in seemingly comparable methods.