Packaging has become an indispensible element in the food manufacturing process, and different types of additives, such as antioxidants, stabilizers, lubricants, anti-static and anti-blocking agents, have also been developed to improve the performance of polymeric packaging materials. Recently the packaging has been found to represent a source of contamination itself through the migration of substances from the packaging into food. Various analytical methods have been developed to analyze the migrants in the foodstuff, and migration evaluation procedures based on theoretical prediction of migration from plastic food contact material were also introduced recently
Polyethylene, polyvinyl chloride and allied compounds are used to produce flexible packaging material. While this method of packaging is very convenient, it must not contain any noxious thermal breakdown products which could be injurious to health. Further, temperatures used for heat sealing, or sterilization should not result in formation of toxic residues. It has been observed sometimes that in foods like pickles the acid and oil could attack the plastic packaging material and create a health hazard. To avoid such incidences, it is essential that only food grade plastic packaging materials be used for packaging foods.
These include adulteration of legumes with imported toxic lentils and local Subabul (Lencana leucocephala) seeds, veterinary drug residues in milk, flours made from mouldy wheat, strychnos potatorum, a forest produce in arecanut, animal fat in bakery products and industrial contaminants like orthonitro aniline in vanaspathi.
The Lathyrus sativus, Lens Culinaris (lentils) and Vicia sateva are three closely related species containing unusual amino acids which are used to adulterate some dhals.
Some times Turkish lentil which contain the diaminopropionic derivatives is sold as Indian red gram (Cajanas cajan) dhal and Australian vetch (Vicia sativa) which contains toxic amino acid pcyanoalamine is sold as Indian masur dhal (Lens culinaris) .
Dry ginger is often coated with a blue coloured dye ultramarine blue to prevent insect infestation. It is an inorganic pigment used as laundry whitener.