What You Need to Know
During 24–48 h of fermentation at 4–8 °C, lactic acid bacteria convert sugars in the blood‑pork mixture to lactic acid, dropping the pH to 5.0–5.5 and creating an acidic environment that suppresses spoilage microbes. Sodium nitrite (≈50 ppm) reacts with hemoglobin to form nitrosylhemochrome, giving the sausage its characteristic pink hue and providing additional antimicrobial activity against Clostridium botulinum. Exposure to air oxidizes hemoglobin to methemoglobin, producing a brownish tint if the mixture is left unsealed for more than 2 h before stuffing.
The Science
Primary Reaction
lactic acid fermentation and nitrite curing