Abstract:
Non-branded deep fried manioc chips were evaluated by following a newly
developed and validated method to determine the migration of Terephthalic acid
(TPA) and Isophthalic acid (IPA) from the frying oils adulterated with PET
bottles to make the snacks crisp and long last. Reporting method was comprised
of Soxhlet extraction of oils from 400 deep fried manioc chip samples, solvent
extraction of TPA and IPA using centrifuged oil samples, sample preparation for
High Performance Liquid Chromatography (HPLC) analysis of samples along
with the TPA and IPA standard series. The percentage recovery range for TPA
and IPA was in between 80-120% for 20 manioc chip samples fried in edible oils
incorporated with PET bottles. The results showed that the specific migration of
TPA and IPA into the manioc chip samples conform to European Union
legislation that identifies specific migration limits (SML). The intraday assays for
TPA and IPA were expressed as Relative Standard Deviation (RSD) 5.123% and
2.015%, respectively while inter-day precision assays for TPA and IPA were
expressed as RSD 2.089% and 2.105% respectively. Results highlighted that the
data is tightly clustered around the mean with a good precision. Analytical
curves for TPA and IPA were found to be linear over a wide concentration range
(6 – 120 ppb) with a correlation coefficient of 0.998 for TPA and 0.999 for IPA.
The lower limit of quantification was determined to be 6 ppb, with a RSD lower
than 10%. TPA and IPA in sample are well separated from each other and from
the background oil. The study shows that the method presented in the
methodology can be used as a suitable method for analytical determination of
TPA and IPA in deep fried crispy snacks like manioc chips with high precision
and accuracy.
