Zinc is a vital trace element for our bodies. However, the ingestion of increased amounts of dissolved zinc results in poisoning symptoms immediately after intake. Zinc is used as metal coating in technology, dissolving easily when in contact with acidic foods (e.g. apple juice).
Nickel is a trace element that is an essential part of all stainless steels, but can get into food through mechanical abrasion or chemical effects caused by acidic foods. Thus, only material expressly suited and authorised for foods should be used in their processing and storage.
Mycotoxins -- secondary metabolic products of moulds -- are of special interest as food contaminates. Patulin is an issue, particularly in the production of juices from pomaceous fruit. Patulin is classified as genotoxic, teratogenic and extremely damaging to the liver. The substance is relatively temperature-resistant, especially at acidic pH levels. Patulin mostly occurs in mould-infested fruit. The mould is often caused by insects in otherwise healthy fruit tissue on the inside of the fruit and leads to the occurrence of patulin inside fruit with no visible damage to the outside.
"Commission Regulation (EC) No. 1881/2006 of 19th December 2006 setting maximum levels for certain contaminants in foodstuffs" has defined the maximum levels of patulin in fruit juice in the European Union since November 2003. Very low levels have been specified for children’s foods.
The European Commission compiled its "Commission Recommendation of 11th August, 2003 on the prevention and reduction of patulin contamination of apple juice and apple ingredients in other beverages (2003/598/EC)" for businesses in the apple processing industry.