In order to explain the "amtlich" bit:

In this Act “authorised officer”, in relation to a food authority, means any person (whether or not an officer of the authority) who is authorised by them in writing, either generally or specially, to act in matters arising under this Act; but if regulations made by [F6the Secretary of State] so provide, no person shall be so authorised unless he has such qualifications as may be prescribed by the regulations.

http://www.legislation.gov.uk/ukpga/1990/16/section/5

Food sampling:

Food sampling is a process used to check that a food is safe and that it does not contain harmful contaminants, or that it contains only permitted additives at acceptable levels, or that it contains the right levels of key ingredients and its label declarations are correct, or to know the levels of nutrients present.

https://en.wikipedia.org/wiki/Food_sampling





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Note added at 18 hrs (2018-08-03 15:46:47 GMT)
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Or Just:

Authorised food officer

https://www.businesscompanion.info/en/quick-guides/food-and-...