Food Waste on the Agenda Key factors to be considered Sigrid Kusch Faculty of Engineering and the Environment University of Southampton Southampton, UK Abstract—Huge amounts of food waste are generated worldwide. Efficient valorisation strategies ensure that embedded energy and resources are at least partially recuperated. Food waste is a highly biodegradable material with high water content, and as such well destined for biogas production through anaerobic digestion. In order to ensure successful implementation of food waste valorisation via anaerobic digestion, a range of key factors related to the characteristics of the material as well as to more general frameworks need to be considered. Keywords- food waste management; biogas; anaerobic digestion; bioenergy I. INTRODUCTION Occurrence of food waste is a factor that significantly decreases efficiency of a food system. Along with reduction of wastage, valorisation of not avoided food waste is at the heart of the challenge to establish a more sustainable food system. Despite the fact that bioenergy production, and in particular biogas production, has been and is further studied by many research groups worldwide, it requires increased commitment from stakeholders and availability of key knowledge to encourage more widespread and successful uptake in practice. This publication aims at compiling key factors to be considered when looking at possible valorisation of food waste. II. WASTE IN THE FOOD SYSTEM There is no consensus what the term food waste comprises. The term may refer to lost or degraded material which was originally destined for human consumption, or might include edible material intentionally fed to animals or by-products of food processing diverted away from human consumption, or might even refer to over-nutrition as the gap between consumed and needed per capita food energy [1]. In the following, food waste refers to all losses and inedible by- products in the food supply chain (FSC) after that material was designated to human consumption purpose (including potentially consumable material left on field), which is in line with the majority of literature in the area. Food waste is generated at all stages of the food supply chain (Figure 1). So-called post-consumer waste comprises food wastage which occurs at the point at which food is consumed, e.g. meal preparation waste, left-over and discarded food, while food occurring during earlier stages of the supply chain can be summarized with the term pre-consumer waste. Nevertheless, the characteristics of the waste at each single step of the FSC can significantly differ from the next step, and might among others depend on the individual food type, management, preferences and engineered infrastructures. At all stages, not all food losses would potentially be avoidable. Food is a biological material susceptible to degradation and which requires processing before it can be consumed, so occurrence of material which cannot be served as food is to some extent unavoidable. Figure 1. Food waste in the food supply chain Amounts and characteristics of food wastes are highly related to the economic development stage of a country. Financial, managerial and technical limitations in harvesting techniques, in storage and cooling facilities, in transport infrastructures, and in packaging and marking systems are most relevant in low-income countries, while in medium and high SECTION 11. Ecology, Forestry, Earth Science I N T E R D IS C I P LI N A R Y C O N F E R E N CE EIIC The 2nd Electronic International Interdisciplinary Conference http://www.eiic.cz/ Electronic International Interdisciplinary Conference September, 2. - 6. 2013 - 343 -