Scalping phenomena: sorption kinetics of white wine aroma compounds into HDPE, PET and PLA

Plastics packaging for wine is not very popular, though it offers several advantages such lower environmental impacts and lower cost compared to glass, and may represent a viable alternative especially for short-lived products. However, it is crucial to investigate the packaging-product interaction and its possible impact on wine flavor stability. The scalping of aroma compounds by plastics, indeed, may negatively impact the sensory quality of wines by altering the aroma profile. The present study evaluates the sorption kinetics of four volatiles (ethyl hexanoate, ethyl octanoate, ethyl decanoate and phenethyl alcohol) characteristic of white wine, into HDPE, PET and PLA. The extent of scalping was evaluated combining MHS-SPME technique for volatiles extraction, which allows a quantitative evaluation of the compounds of interest absorbed in solid matrices, and GC-MS analysis for the identification and quantification of the compounds. The experimental data of volatiles sorption kinetics were fitted by a mathematical model based on Fick’s second law. Results highlight a higher affinity of esters and alcohols for HDPE while PET and PLA showed lower sorptive power compared to HDPE. PLA showed a comparable behaviour to PET, both standing as valid alternative materials to glass for short-lived wines.