Evaluation of portable vibrational spectroscopy for identifying plasticizers in dairy tubing

ABSTRACT

Plasticisers are commonly used to increase the flexibility of a wide variety of food contact materials including the plastic tubing, liners, and gaskets used in the dairy industry. In recent years, some classes of plasticisers have come under scrutiny due to the potential for transfer of these compounds into the milk itself, which can then be further processed into foods such as powdered milks and cheeses, infant formula, and baked goods. One such set of plasticisers that is being evaluated for frequency of use, potential routes of exposure, and risk to consumers is ortho-phthalates, hereafter referred to as phthalates. In order to better understand the actual use of phthalate versus non-phthalate plasticised tubing, a robust, rapid, and portable analytical method is necessary for on-site screening. Laboratory Raman and near-infrared spectrometers have been used extensively for polymer and additive evaluation, and advances in portable/hand-held technology could lead to feasible plasticiser evaluation in the field. This research overviews efforts to evaluate six portable spectroscopy devices for their ability to identify phthalate versus non-phthalate plasticised polyvinyl chloride (PVC) dairy tubing, liners, and gaskets. The most successful method, a hand-held Raman spectrometer along with a plasticiser spectral library or a chemometric model, can rapidly and accurately identify phthalate containing PVC and has the potential to be employed as a future field screening technique for regulators and the dairy industry.

KEYWORDS:

• Food contact
• ortho-phthalates
• chemometrics
• near-infrared
• Raman spectroscopy

Acknowledgments

Thank you Milk Barn/Agri-Service (Hagerstown, MD) for their insights into the dairy industry. The authors would also like to thank Dr Sam Timpa for providing the PVC sheet samples from BASF. Dr Moskowitz acknowledges the support provided by an appointment to the Research Participation Program at the Center for Food Safety and Applied Nutrition, administered by the University of Maryland, Joint Institute for Food Safety and Applied Nutrition through a cooperative agreement with the FDA, #FDU001418.

Disclosure statement

No potential conflict of interest was reported by the author(s).

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Funding

The author(s) reported that there is no funding associated with the work featured in this article.