The kinetics of swelling and migration: A case study of plasticized polylactic acid food contact plastics tested with ethanolic food simulants
Viktor Konstantin Dragan
, Noémi Petrovics
, Csaba Kirchkeszner
, Tamás Tábi
, Bálint Sámuel Szabó
, Zsuzsanna Eke
, Noémi Petrovics
, Csaba Kirchkeszner
, Tamás Tábi
, Bálint Sámuel Szabó
, Zsuzsanna Eke
Vol. 18., No.4., Pages 391-405, 2024
DOI: 10.3144/expresspolymlett.2024.29
DOI: 10.3144/expresspolymlett.2024.29
GRAPHICAL ABSTRACT

ABSTRACT
The
effect of swelling and plasticizer content of a plastic, as well as the ethanol
content of the food simulant on the migration kinetics of three stabilizer-type
additives from polylactic acid (PLA)-based food contact plastics has been
investigated. The results proved that the parameters that affect the diffusion
of substances inside the polymer matrix, i.e.,
swelling, plasticization, and the size of migrants, are the decisive factors in
the migration from PLA to ethanolic food simulants. Both swelling and migration
were negligible when ethanol 10% (v/v) was used. Contrarily, the specific
migration limits of Commission Regulation (European Union, EU) No. 10/2011 were
exceeded in ethanol 50% (v/v) for all investigated stabilizers. Migration was
promoted by plasticization, but this effect could only be observed when the
applied food simulant swelled the plastic (at least 20% (v/v) ethanol content).
The dependence of the plasticizer’s migration-enhancing effect on the swelling
has not been shown before. When the plasticization caused increased migration,
it also led to specific migration limit exceeding within a shorter period of
time. It happens even if PLA-based plastics are dedicated to the storage of
hydrophilic food, which is the most common application area of these products.
These results can support the improvement of both consumer safety and active
packaging development.
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