Elimination of a Flavor Defect in Milk Treated for Iodine-131 Removal by Ion Exchange

Abstract

Milk processed through a regenerated anionic resin revealed a flavor defect that required discarding the initial resin bed volumes (rbv) of treated milk. Most of this flavor defect was eliminated by removing a 1% nonionic detergent (Triton X-100) solution treatment that had been used to wash the milk residue from the resin during regeneration. The milk flow rate was increased from 0.12 to 1.0 rbv/minute to decrease additional flavor loss caused by iodine-131 removal processing. Milk was then passed through an anionic resin (Dowex 2-X8) in a chloride:phosphate:citrate cycle at 1.0 rbv/minute for five processing cycles of 175 rbv each. Between the fourth and fifth cycles, the resin was regenerated through the 2 n HC1 (industrial grade) strip, then stored in pH 2 solution for one month. The flavor was acceptable on all five cycles without discarding any treated milk and without employing HC1 of reagent grade to strip iodine-131 from the resin. Approximately 96% of the iodine-131 was removed from milk processed through an anionic resin at 1.0 rbv/minute for 175volumes.