AOAC OMA# 2011.14 (Final Action Review)-OMB

2011.14 (Oct. 2018) – MTE-03 Final Action Review FOR ERP USE ONLY DO NOT DISTRIBUTE

without sealing. Predigest for at least 10 min at room temperature or until vigorous foaming subsides. Close MDC vessels and distribute onto microwave carousel to ensure uniform microwave power application on all samples. ( c ) Test portion preparation with MDO flask or tube.– ( 1 ) Infant cereals or fortified milk powders .–Accurately weigh 1.00 ± 0.01 g into a 100 mL volumetric flask for MDO. ( 2 ) Milk and whey .–Weigh 4.0 g to the nearest 1 mg into the MDO flask or tube. ( 3 ) Dried milk, dried whey, and infant formula .– Weigh 1 g powdered product to the nearest 1 mg (or sample mass on a dry weight basis in the prepared slurry) into the MDO flask or tube. ( 4 ) Cheese.– Weigh 0.3 g to the nearest 1 mg into the MDO flask or tube. ( 5 ) Butter .–Weigh 0.5 g to the nearest 1 mg into the MDO vessel. ( 6 ) Blank.– In parallel with test portion digestions and analyses, carryout a blank test using the same procedures and reagents. ( 7 ) Carefully add 5.0 ± 0.1 mL HNO 3 and then 5 mL H 2 O 2 into MDO flask or tube. Predigest for at least 10 min at room temperature or until vigorous foaming subsides. Distribute flasks or tubes onto microwave carousel to ensure uniform microwave power application on all samples. [ Note : An optimal analytical test portion mass of 0.5 g (1.0 g for MDO) is based on an empirical maximum energy release by the food of 3 kcal and 90–110% recovery.] [ Note : Line the MDC vessel walls or Pasteur pipet with weighing paper during sample transfer to keep sample from adhering to sides of vessel or use a Pasteur pipet to transfer liquid samples. Remove weighing paper from sample prior to next step. Weigh fluid samples or test portion from slurry test sample directly after mixing.] ( d ) Food-grade salt sample preparation .—Weigh 0.20 ± 0.01 g food-grade salt into a 100 mL volumetric flask. Add deionized water and 10 mL HNO 3 . Dissolve salt and dilute to volume with deionized water.