AOAC 981.10
Nitrogen in meat and meat products (reference method) — listed together with ISO 937.
Nitrogen content of meat and meat products by the Kjeldahl reference method; Sonnen's application list pairs AOAC 981.10 with ISO 937.
Meat and meat-product testing laboratories determining crude protein for composition and labelling.
Method principle.
Kjeldahl: catalytic digestion in concentrated sulphuric acid, alkaline steam distillation into boric acid, then titration of the absorbed ammonia. Read the full Kjeldahl method note →
Sonnen's published application list references AOAC 981.10 together with ISO 937 for nitrogen in meat and meat products. Confirm the current method text and scope in the AOAC compendium before compliance use.
Laboratory workflow.
Digestion
The sample is digested in concentrated sulphuric acid with a catalyst on a digestion block (Smart, X, S or Gr series), converting organic nitrogen to ammonium.
Distillation
Alkali is added and steam distillation releases the ammonia, which is absorbed in boric acid — automated on every K-series analyzer.
Titration
The absorbed ammonia is titrated to a colorimetric end point detected by a 16-bit tri-primary color sensor (built in on K06, K12, K18 and K1306; external on K1305/K1301).
Data handling
Results are calculated, stored and exported — K12/K18 store up to 5,000,000 test results with USB, Wi-Fi and host-control output; K18 adds LIMS connectivity.
FAQ.
Which SONNEN analyzers list AOAC 981.10?
Working to AOAC 981.10?
Tell us your sample type — we will map the instrument to the method.