Of course, and it takes often time to find out about the true origin and the real ingredients!
And many consumer organisations, and with them, public control services, are investigating since many years, but too often, they are facing closed doors and "professional or manufacturing" secrets. Also public authorities can rarely intervene against well protected multinational trusts.
Even fruits, crops and vegetables labelled with "local production", or "fair trade" and "bio" might have been contaminated by pesticides from more or less neighbouring industrial cultures, or packed abroad, mixed with imported goods, or treated to prolong the shelf life, etc. And also fraud and adulteration are going on - since very long.
Here's an article in English:
https://www.theguardian.com/lifeandstyle/2015/feb/21/a-feast-of-engineering-whats-really-in-your-food
About food scandals:
https://en.wikipedia.org/wiki/List_of_food_contamination_incidents
http://www.forbes.com/sites/larryolmsted/2016/07/11/fake-food-scandals-a-bad-year-for-food-lovers/#158ef2293202
http://www.foodiejunky.com/10-biggest-food-scandals-that-shook-the-world/
https://en.wikipedia.org/wiki/Food_industry
The problem is that as good as everybody is being lied at and fooled.
This old parody - a fiction not thought (really?) to warn against mass production, big food industries and their bosses, but to entertain with much sarcasm - illustrates very well what really happened and still happens behind closed doors:
https://en.wikipedia.org/wiki/The_Wing_or_the_Thigh
About how a chicken is manufactured: