EFFECT OF GAMMA-RADIATION ON MIGRATION BEHAVIOR OF DIOCTYLADIPATE ANDACETYLTRIBUTYLCITRATE PLASTICIZERS FROM FOOD-GRADE PVC AND PVDC PVC FILMS INTO OLIVE OIL/

Food-grade PVC and PVDC/PVC films containing 28.3 % dioctyladipate (DO A) and 5.0 % acetyltributylcitrate (ATBC) plasticizers, respectively, were brought into contact with olive oil and were irradiated with gamm a-radiation [Co-60] at doses equal to 4 kGy and 9 kGy corresponding to ''cold pasteurization''. irradiation was carried out at 8-10 degrees C and samples were subsequently stored at 4-5 degrees C. Contaminated oil samples were analysed for DOA and ATBC at intervals between 7 h an d 97 h of contact, using an indirect GC method. identical nonirradiate d (control) samples were also analysed for DOA and ATBC content. Resul ts showed no statistically significant differences in migrated amounts of DOA and ATBC between irradiated and non-irradiated samples. Neithe r were differences observed between samples irradiated at 4 kGy and 9 kGy. This was supported by identical LR spectra recorded for irradiate d and non-irradiated samples and leads to the conclusion that at such intermediate radiation doses (less than or equal to 9 kGy) the migrati on characteristics of both PVC and PVDC/PVC films are not affected. Th e amount of DOA that migrated into olive oil was dependent on time, re aching equilibrium after approximately 47 h of contact (302.8 mg/l). T he amount of ATBC that migrated into olive oil was non-detectable (< 1 mg/l) for all samples stored at 4-5 degrees C after 97 h. In non-irra diated samples (PVDC/PVC in contact with oil) stored at 20 degrees C, small amounts of migrated ATBC were determined (3.3 and 5.1 mg/l after 29 h and 94 h of contact respectively). Furthermore, in thermally tre ated samples heated to 80 degrees C for 30 min and 60 min, the respect ive amounts of migrated ATBC determined were 2.9 mg/l and 19.3 mg/l.