Environmental Engineering Reference
In-Depth Information
Organic waste at these stages is the result of expiration, spoilage, quality, and cosmetic rea-
sons. Some products are discarded because they are close to reaching the expiration date or due
to spoilage. Other products, such as bread, are discarded because of quality deterioration even
when they are suitable for consumption, but they do not have the freshness expected by custom-
ers. Produce, in particular, is discarded because of spoilage, overripening, or because of blem-
ishes. Overall, total losses of food at the retail level are about 2 percent (Kantor et al., 1997).
During consumption
Consumption of food at home, restaurants, or institutions produces both organic and inor-
ganic wastes. The organic component consist of food scraps, spoiled and expired food,
brown grease, and kitchen wastes such as peels, stems, seeds, and trimmings. The amount of
food waste generated by consumers in the United States before recycling reaches 34 million
tons a year, which represents 14 percent of the total municipal solid waste stream. Less than
3 percent is recycled, so 33 million tons are landfilled or incinerated (“Food Waste,” n.d.).
It is estimated that in the United States, an average 26 percent of the food that reaches the
customer (e.g., households, foodservice, grocery stores, and institutions) goes to waste
(Kantor et al., 1997). Losses are a combination of uneaten food, preparation scraps, food
reaching expiration date, spoilage of perishable products, and biological deterioration of grain
products. Figure 10.3 compares the food consumed versus food loss for different categories of
food products.
Inorganic waste resulting from food consumption is essentially packaging material, which
includes primary packaging made of cardboard, aluminum, glass, plastics, textiles, or steel and
secondary packaging constructed mainly with cardboard, wood, and shrink-wrap films.
Food eaten
Food lost
Fresh fruits and
vegetables
Fluid milk
Processed fruits and
vegetables
Meat, poultry, and fish
Grain products
Caloric sweeteners
Fats and oils
Other
0.0
5.0
10.0
15.0
20.0
25.0
30.0
Billion kilograms
Note
: “Other” includes eggs, peanuts, tree nuts, dry beans, peas, and lentils, and
dairy products other than fluid milk.
Figure 10.3
Food losses of different food products in the United States during 1997.
Adapted from Kantor et al., 1997.
