AOAC Official Method 935.48« Nitrates and Nitrites in Meat
Xylenol Method
First Action 1935
Surplus 1994
Final Action 1996
A. Apparatus
Use simple distillation apparatus, including distillation bulb.Type of glass condenser utilizing thin, rapidly moving H2O film as cooling medium (West type) is recommended.
B. Reagents
(a) m-Xylenol.—2,4-Dimethylphenol. Eastman Kodak Co. No.1150, or equivalent.
(b) Silver–ammonium hydroxide solution.—Dissolve 5 g nitrate-free Ag2SO4 in 60 mL NH4OH. Heat to bp, concentrate to ca 30 mL, cool, and dilute to 100 mL with H2O.
(c) Bromocresol green indicator.—Dissolve 0.1 g bromocresol green in 1.5 mL 0.1M NaOH, and dilute to 100 mL with H2O.
(d) Nitrate standard solution.—Dissolve 0.1805 g recrystallized KNO3 in H2O and dilute to 1 L, or dilute 17.85 mL 0.1M HNO3 to 1 L; 10 mL contains 0.25 mg nitrate N.
