ESTIMATION OF MINERAL OIL RESIDUES IN SOIL AND APPLE FRUIT BY GAS CHROMATOGRAPH WITH FLAME IONIZATION DETECTION (GC-FID)

摘要

The present invention concerns a method to quantify mineral oil residues in foods and food products (such as apple fruit and soil). The method involves dry the sample, crush and then Pass through sieve and spike 150 gm of sample with paraffin standard at 1µg g-1 then mix with 20g of anhydrous sodium sulphate, put the mixture in soxhlet thimble and Reflux with refluxing solvents for 4 hours, After that take 30ml of sample and dry over anhydrous sodium sulphate, after that take 2ml of extract in rotary vacuum evaporator and evaporate to near dryness, Reconstitute with 1ml hexane, Filter through 0.22 µm Polytetrafluoroethylene (PTFE) filters, Transfer the extract in 1ml autosampler vial and analyze on GC-FID.