The global food industry generates 2.5 billion tons of food waste annually, of which over 30% is lost or wasted. This contributes 8–10% of greenhouse gas emissions and results in economic losses of USD 1 trillion 1, 2. Food waste, broadly defined as food intended for human consumption that is discarded or lost, occurs throughout the supply chain — from post-harvest processing, storage, handling, and transportation to consumer-level waste from uneaten food. Industrial food waste sources, such as those from agriculture, seafood, dairy, and poultry industries, primarily consist of inedible discards or spoiled harvests. In contrast, urban food waste stems from households, restaurants, bakeries, supermarkets, and unconsumed food. Traditional disposal methods, including landfilling and incineration, not only produce significant greenhouse gas emissions but also contribute to ecosystem acidification and eutrophication [3], highlighting the urgent need for more sustainable solutions. This review will explore approaches to food waste valorization, the role of synthetic biology in advancing these efforts, and the challenges associated with commercialization in this field.