Meeting Abstract
O-78
New GPC method for methylcellulose and hydroxypropyl methylcellulose food gums as soluble dietary fiber in foods. R. G. Harfmann (1), M. TUROWSKI (1), J. R. Conklin (1), B. K. Deshmukh (1), S. K. Lynch (1). (1) The Dow Chemical Company, Midland, MI, USA.
Methylcellulose (MC) and hydroxypropyl methylcellulose (HPMC) food gums are water-soluble celluloses, which resist digestion in the human GI tract and exhibit health benefits associated with soluble dietary fiber. Due to their solubility in 80% ethanol solutions they not precipitate during analysis by AOAC methods 985.29 and 993.41. A method has been developed and validated to quantify MC and HPMC in food and food products. It uses the same enzymic digestion principle as AOAC methods, but employs GPC analysis of the aqueous reaction mixture instead of gravimetric determination. The results of single-lab and collaborative study protocol will be presented, previously approved by AOAC to determine method suitability for official AOAC recognition. 14 independent laboratories entered the study and results of those that completed to date indicate repeatability and reproducibility with RSD values at levels typical for such collaborative efforts.