Source: FAO (2011) Global Food Losses and Food Waste.
There are five major sources of food waste along the food supply chain:
- Agricultural production. For fruits, vegetables, and cereals, harvesting can be a source of losses of the food product that is damaged mechanically, spilled, or threshed. Meat losses are accounted for by animal deaths during breading. For fish losses, they represent discarded specimens (improper size or species) during fishing.
- Postharvest handling and storage. Spillage and degradation losses taking place after the harvest as the food items are stored at the production unit. For meat, it includes losses during transportation to slaughterhouses. For fishes, it involves losses while icing, packaging, and storage once a fishing ship has reached the shore.
- Processing. Losses when food items are processed, such as washing, peeling, slicing, boiling, or other forms of more advanced processing (e.g. mixing, baking). Some items, particularly fruits and vegetables, can also be discarded if judged not of the right shape and size (consumer preferences). For meat, losses are during cutting and trimming. For fishes, it includes losses during canning and smoking.
- Distribution. An array of losses once food items are distributed through the market system (wholesalers, distributors, grocers) and often linked with inadequate storage and transportation or unforeseen delays resulting in spoilage.
- Consumption. Losses and waste during consumption at the household level, which can include during storage and preparation. It considers food items that are not consumed and discarded.