There have been many reports of mcdonalds burgers and chicken products having plastic components found inside them, one being known as "silly putty" no its not a joke!
A CNN report said chicken McNuggets contain the chemical preservative TBHQ, or tertiary butylhydroquinone, a petroleum-based product, this is toxic waste from oil after it has been refined.
many "fanatics" have conducted experiments where they have left burgers in isolation for up to months to years to come back to them looking brand new as if it was just bought.
This might explain it:
http://english.peopledaily.com.cn/90001/90778/90860/7053840.html
It has been no secret as for years all fast food restaurants around the globe, but most severe in the coorporation known as the UNITED STATES, have been using plastics and anti-foaming agents to preserve food and make it last longer as it sits to be bought by its victim