Sub Zero Polypropylene Grade Selection for Packaging Molders
Heterophasic polypropylene copolymers with controlled rubber dispersion prevent brittle container shattering during sub-zero cold chain transport and drop impact.
Organoleptic Properties
Meaning
Sensory characteristics of a material including its taste and smell define how it interacts with the human senses during use. Assessing organoleptic properties is a critical step in the development of plastics intended for food contact or potable water transport. These traits are determined by the presence of volatile organic compounds that can migrate from the polymer into the contents of a package.
The evaluation stops being relevant for industrial parts that never come into contact with consumers or sensitive products.
Migration Mechanism
Small molecules from the resin or its additives move through the plastic matrix and enter the surrounding medium. Since organoleptic properties are affected by temperature and contact time, testing often involves storing water in a container for several days before tasting. High temperatures can accelerate the release of these compounds.
These migrations can create off flavors or metallic scents in bottled water.
Consumer Acceptance
Perception of a product quality is often tied to the absence of any detectable plastic odor. If the organoleptic properties of a package are poor, the consumer may perceive the food inside as being contaminated or expired. Brands spend resources to ensure that their materials are neutral.
Neutrality is especially difficult to achieve with recycled plastics.
Material Certification
Labs use panels of trained human testers and gas chromatography to verify that a resin is suitable for sensitive applications. While chemical analysis identifies specific molecules, the human nose is often better at detecting the complex mixtures that influence organoleptic properties. Passing these tests is a requirement for many global food safety standards.
Consistent batches are necessary to maintain a reliable supply of high quality packaging. Evaluation of these traits ensures that the plastic does not compromise the flavor of the final product.