Chemical Residual
Low molecular weight polymers formed during the production of polyethylene and polypropylene are found as unintended by-products in many plastic materials. Food safety assessments investigate polyolefin oligomers due to their potential to migrate from packaging into the contained products.
Migration Path
Small molecules move through the porous structure of paper or cardboard when plastics are used as coatings or adhesives. These polyolefin oligomers are classified into two groups based on whether they are saturated or unsaturated. Saturated versions are often referred to as mosh while the unsaturated versions are called moah.
Analytical testing identifies these compounds to ensure they stay below safety limits.
Control Mechanism
Selection of high-grade resins and optimized extrusion parameters reduces the formation of these short-chain molecules. Monitoring the temperature during the coating process prevents the breakdown of the polymer into additional polyolefin oligomers. Functional barriers like aluminium foil or specialty films block the movement of these substances.
Testing the finished pack over time reveals how much material reaches the food. Manufacturers must balance the need for strong seals with the requirement for low migration. Regular audits of the supply chain ensure that virgin resins are not contaminated by recycled materials.
Precise laboratory methods are needed to distinguish these compounds from natural waxes.
