Planet Earth is under severe stress due to imbalances in production, consumption, abuse and misuse of natural and man-made resources and, poor climate control. Our resources will be further stretched as global population increases from 7 billion today to over 9 billion by 2050. Industrialised nations are resource intensive societies heavily reliant of crude oil (petroleum) and gas for their energy, chemical and material needs based on traditional manufacturing processes. However, crude oil is a finite resource and its continued use represents a major environmental burden. Thus, development of new manufacturing processes and technologies based on alternative feedstocks, i.e., biobased and ideally produced as a waste or currently under-utilised, within the confines of a sustainable circular economy is of paramount importance nationally and globally. Food and drink is the largest manufacturing sector in the UK, employing approximately 400,000 people with a turnover of £76 billion. Food manufacturing is a complex process that is in the main linear- rather than circular-thinking. A staggering 9.9 million tonnes of food waste and food by-products are generated per year in the food industry alone, of which 56% is considered unavoidable. Unavoidable food supply chain wastes (UFSCW) lost after harvest and along the distribution and consumption chain have a dual negative environmental impact: undue pressure on natural resources and ecosystem services and pollution through food discards. However, current strategies for dealing with UFSCW are rudimentary and of low value: these include waste to energy (including incineration and anaerobic digestion), where possible; animal feed and bedding; compositing; ploughing back in to soil; and, least preferable, landfill. UFSCW is unique as a bioresource: this readily available biomass contains a treasure trove of unexploited, bio-based materials and chemicals, with a range of potential commercial applications. Our aim is to develop a whole 'systems' understanding of upgrading and re-utilisation of unavoidable food supply chain wastes, [namely: brewers' spent grain; pea vine waste; out of specification citrus fruits; and out of specification potatoes], as a source of functional food ingredients. These four feedstocks are representative examples such that our methodologies and findings will be applicable to a wider range of feedstocks. Furthermore, key performance indicators such as amount of waste, pattern of generation, possible contamination with other food waste, seasonality, etc. will be used to develop an appropriate whole system thinking around food waste collection, reprocessing, and production of new food products. The ultimate objective of our proposed research is to achieve a whole systems thinking "closed-loop" manufacturing of food products, with all input materials fully utilised. The ramifications and any unintended consequences associated with the proposed alternatives will be assessed, at an industry level, working with previously identified partners, and within a broader scope, determining the consequences of these changes in the entire UK food manufacturing sector, linking into the work of the highly networked EPSRC Centre for Innovative Manufacturing in Food.