Recently there have been many cases wherein foreign bodies have been found in food in the UK. Foreign bodies are any undesirable solid objects in food which are entirely unconnected with the food in question. 
Food is commercially produced these days at such large scale that often hygiene goes for a toss.
The list of foreign objects which have been found in food is almost endless. Metal , plastic and glass fragments,insects,egg shells,bone fragments etc have all been found in food at one or the other time and many general food hygiene regulations are aimed at eliminating possible sources of foreign objects in food during preparation procedures. Some of these regulations are wearing of hair covers by workers, guards over adhesives or bandages on workers, the prohibition on smoking, and the removal of jewellery before entering a food processing.
The causes of foreign bodies in food are accidental as well as criminal. One malicious contamination case was caused by a factory worker “who was feeling a bit down” and picked up a handful of broken windscreen glass, later putting it in a crispy pancake.
Most companies method of transmitting low power microwaves through the material. The microwave radar can detect objects from 2 – 3 mm. Other companies use mechanical separation techniques for finding foreign objects in powdered and flowing products on the basis of size and weight. Some also use low intensity ultrasonic techniques because of their large applicability, reliability, safety and low cost. However still some objects remain unidentified.
Via:IOL
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