Determinação de contaminantes em bebidas não-alcoólicas acondicionadas em garrafas PET Pós-Consumo Recicladas (PET-PCR)

Abstract

The production of bottles PET (polyethylene terephtalate) for the preservation of foods grows gradually, and to prevent damages to the environment, a solution is the recycling, generating the post consumer recycle food-grade PET (PCR PET). From the bottles can have migration of contaminants to the food or drink. The present study intended to determine possible contaminants in PCR PET, to evaluate if there is migration to the not-alcoholic drinks and to propose methodologies that take care of these objectives. Bottles were used as samples, cut in flakes,made of 100% recycled resin PET. In the methodology, using gas chromatography, with column DB-624, and sampling for headspace, with detector for ionization in flame, had been identified contaminants in the PET, being acetaldehyde the main contaminant of found toxicological relevance. The other identified components had been etanol, 2-butenal, butanal, derivatives of acetaldehyde, and linoleic acid and oleic acid. For confirmation it was used gas chromatography with headspace, and detector for mass spectrometry. For the tests of migration of acetaldehyde for not-alcoholic drinks, the acid 4-hidrazinobenzoic was used (HBA) as agent of derivatization for carbonilic compounds in two simulants: distilled water, corresponding to the water mineral, and acetic acid, corresponding to cooling juices and refrigerants. After that, analysis for spectrophotometry was carried through, where the concentration of the formed derivative was measured in the wave length of 290 nm. In the migration tests three conditions of temperature and time had been simulated: 40ºC per 10 days, simulating storage in the commercial establishment; 60ºC for 4h, simulating the conditions of transport for drink deliverers; and 60ºC per 10 days, representing extreme conditions. These methods of determination of the acetaldehyde migration had presented for the water simulation agent linear band from 4,44 to10,36 mg/L and limits of detection and quantification 0,718 mg/L and 2,10 mg/L respectively. For the acetic acid simulation agent, the linear band was of 3,15 – 9,41 mg/L, and limits of detection and quantification 0,093 mg/L and 0,279 mg/L, respectively. The acetaldehyde has raised potential mutagenic and carcinogenic, then its production in the manufacture of bottles PCR PET must be prevented and be monitored. There is, therefore, necessity of constant fiscalization of bottles PCR PET and stored not-alcoholic drinks in these bottles, in order to provide greater alimentary security to the consumers.