Livestock's Long Shadow "that livestock are responsible for 18 percent of greenhouse gas emissions" GHG emissions arise from feed production (e.g. chemical fertilizer production, deforestation for pasture and feed crops, cultivation of feed crops, feed transport and soil organic matter losses in pastures and feed crops), animal production (e.g. enteric fermentation and methane and nitrous oxide emissions from manure) and as a result of the transportation of animal products. Following this approach the report estimates that livestock contributes to about 9% of total anthropogenic carbon dioxide emissions, but 37% of methane and 65% of nitrous oxide emissions. Along the animal food chain, main
Nitrous oxide and thus creates foam. Used in this way, it produces whipped cream four times the volume of the liquid, whereas whipping air into cream only produces twice the volume. If air were used as a propellant, oxygen would accelerate rancidification of the butterfat, but nitrous oxide inhibits such degradation. Carbon dioxide cannot be used for whipped cream because it is acidic in water, which would curdle the cream and give it a seltzer-like "sparkling" sensation. The whipped cream produced with nitrous oxide is unstable, however, and will return to a more liquid state within half an hour to one hour.