Blood Fraction Effects on the Antibotulinal Efficacy of Nitrite in Model Beef Sausages

Toxin production by Clostridium botulinum was studied in a model cured beef sausage containing 0–5% added dried bovine blood fractions. Controls which contained nitrite but without blood fractions, were toxic by bioassay in 3 wk at 27°C. Controls without nitrite or blood fractions were toxic at 1 wk, while model sausages supplemented with hemoglobin, red cells, or whole blood were toxic in 1–3 wk. Plasma yielded no detectable toxin for 4 to > 10 wk depending upon addition level. Sausages showing delayed toxigenesis had pH values lower than those which developed toxin earlier. These results demonstrated that use of blood fractions that increased iron levels in beef above 30 μ.g/g interfered with the antibotulinal efficacy of sodium nitrite.