Henry C. Hollifield

Migration into food of polyethylene terephthalate (PET) cyclic oligomers from PET microwave susceptor packaging

A quantitative method has been developed to measure the migration of polyethylene terephthalate (PET) cyclic oligomers from aluminized PET susceptor film-type food packaging into several food types. Microwaveable French fries, popcorn, fish sticks, waffles and pizza sold in susceptor-type packaging were purchased in local markets, cooked according to package instructions and analysed for PET oligomers. Appropriate food blanks were cooked in glass containers. Quantities of PET oligomers found in the foods ranged from less than 0.012 micrograms/g to approximately 7 micrograms/g.

Effects of temperature and mixing on polymer adjuvant migration to corn oil and water

The effect of mixing on the migration of Irganox 1010 antioxidant from polypropylene and high-density polyethylene to water and corn oil was compared at 77, 100, and 135 degrees C. Irganox 1010 migration to water is enhanced almost five-fold by mixing at 77 degrees C, whereas at 135 degrees C, mixing has only a nominal effect on migration. Irganox 1010 migration to corn oil is virtually unaffected by mixing at the temperatures studied. Migration data indicate a similar trend for Irganox 1076.

Determination of migrants in and migration from nylon food packaging

A method was developed to determine the amount of residual oligomers in nylon food packaging. In addition, a method was developed to measure oligomers that migrate to a food-stimulating liquid (oil) during oven cooking conditions. It was found that the total amount of nylon 6/66 oligomers that migrated from an oven baking bag to oil after heating for 30 min at 176 degrees C was 15.5 micrograms/g (ppm) or 11.9 micrograms/cm2, which represented 43% of the total amount of oligomers present in the packaging material.

Evaluation of polyethylene terephthalate cyclic trimer migration from microwave food packaging using temperature‐time profiles

The polymer polyethylene terephthalate (PET) is widely used for packaging food that will be heated or cooked in the PET container. A procedure was developed to predict the potential of PET to migrate from the container into the food. Migration experiments using crystallized polyethylene terephthalate (CPET) and corn oil were performed at 115, 146 and 176 degrees C. From these experiments diffusion coefficients were calculated for the cyclic trimer in PET. By using an Arrhenius plot to obtain the diffusion coefficient and a temperature versus time plot of a microwave susceptor-heated CPET tray, it was possible to predict migration of the cyclic trimer into corn oil under microwave conditions. Predicted values were in good agreement with measured results.

Migration of dibenzoate plasticizers and polyethylene terephthalate cyclic oligomers from microwave susceptor packaging into food-simulating liquids and food

Migration of diethylene and dipropylene glycol dibenzoate and the polyethylene terephthalate (PET) cyclic oligomers from microwave susceptor packaging into oils (food-simulating liquids) and food (french fries) has been determined. The PET susceptor film did not provide a barrier to migration of adhesive components when oils or food were cooked in contact with the PET susceptor film. The dibenzoate plasticizers migrated to a greater extent into oils and food then did the PET oligomers.

Approaches to evaluating high-temperature food packaging materials as sources of food contamination

We have developed several new analytical protocols to provide data for evaluating the safety of high-temperature food-contact articles like microwave susceptors and dual ovenable trays used in cooking and reheating. The improved protocols simulate high-temperature use conditions encountered in both microwave and conventional ovens, and are conducted using food substitutes and test cells appropriate for these environments. They are suitable for the identification and quantitation of multiple volatile chemicals as well as non-volatile adjuvants, oligomers and contaminants. These procedures lend themselves to analysis of various food-contact articles containing poly(ethylene terephthalate), polypropylene, polycarbonate and nylon. Gas chromatography—mass spectrometry, high-performance liquid chromatography and supercritical fluid extraction and chromatography are the techniques used in these tests for analysis of food simulants and extracts.