Packaging is an integral part of complete food supply chain management. Without proper packaging, the quality of the food will be degraded and it may not be stored for longer period. Another important aspect of packaging is to provide an aesthetic look so that it can get proper consumer attention.
There are various kind of packaging terminologies associated with food packaging; when the food is in direct contact with packaging it is known as "primary packaging" or "immediate food wrapping", similarly when food is not in contact with the food or packaged item, it is known as "Secondary Packaging" or "external packaging". In the context of Printing ink, the terminologies are slightly different - when the ink through printing is in direct contact with food, it is known as "direct food contact ink", when it is in indirect contact, it is known as "indirect food contact ink". Sometimes, occasional food contact is also possible such as while using disposables like paper napkins, liquid-food drinking straws etc.
When the chemicals present in printing ink and/or other packaging parts like substrates, adhesive etc. migrate by any means to the packaged-food and contaminate it, the process is known as migration. Migrations are of various types, such as set-off migration, diffusion migration, gas-phase migration etc. That is the reason, it is very essential to control the use of chemicals in the complete process of food packaging and Printing ink is one such important and integral part of packaging as it is a composition of various chemicals such as ink binder, pigments, solvent or monomers, and additives.
Globally, the ink migration regulations use primarily two principles, such as restriction of the ink chemicals through a "Negative List" or through a "Positive List". These phenomena are very easy to understand - a negative list indicates a set of listed chemicals which can not be used in the ink formulation; while on the other hand, the regulation which follows a positive list allows the formulators to choose the chemicals only from the set of positive list. However, the concept of migration limit such as SML (specific migration limt) or OML (Overall migration limit) of chemicals applies here. Usually, it varies even from 60 ppm (parts per million) to 10 ppb (parts per billion) levels. It is worth to mention here that very specialized skill-set is used to understand these chemicals or the its association as impurities in the ink raw materials, while formulating the ink pertaining to various regulations.
In India, the FSSAI (Food Safety and Standards Authority of India) protects the food safety. In the context of Ink standards, FSSAI refers to Indian Standards IS 15495: 2004 which is reaffirmed in 2015 as "Printing Ink for food packaging - Code of practice". Until now, IS 15495 is a voluntary standard as per Food Safety and Standards (Packaging and Labeling) Regulations 2011, however, FSSAI is in process of modifying the regulation through its upcoming Food Safety and Standards (Packaging and Labeling) Regulations 2018; where the use of IS-15495 will be mandatory. The draft version is available in the official FSSAI website for gathering public opinion on the draft version. Anybody can provide their opinions (can be mailed to firstname.lastname@example.org ) by 26th May 2018 using the standard format given in the website.
IS 15495 is applicable for all the four categories of printing ink as mentioned above such as inks for external or secondary food packaging, inks for primary food packaging, direct ink contact on packaging and inks for disposables. There is an exclusion list provided in Annex-A, which is nothing but an negative list. Until now, no official information is available from BIS for any further revisions to IS 15495:2004 (reaffirmed 2015). Please note that commonly used ink-raw materials in Indian market such as Toluene, Titanium acetyl-acetonates, organo-tin catalysts, benzophenone or its derivatives & ITX photoinitiators, harmful cross-linkers etc. are not yet excluded in this Annex-A.
It is always advisable for the ink formulators to go through this IS 15495 as well as FSSAI regulations carefully before formulating the printing ink for food packaging applications in India