Polyesters

Polymers containing ester linkages, a large family that includes PET, the clear polyester behind soft-drink bottles, water bottles, and thermoformed food trays. Their strength, clarity, light weight, and barrier properties have made them dominant in beverage and food packaging. Safety assessment focuses on migration of monomers and additives into food, on controlling acetaldehyde that can taint flavor, and on the quality of recycled polyester, which must be cleaned through validated super-clean processes to food-grade standards before reuse in new containers. Properly manufactured and recycled polyesters are considered safe for direct food contact.