What You Need to Know
The 12–15 % NaCl penetrates the meat, lowering water activity below 0.6 and creating a hyper‑osmotic barrier that dehydrates microbes. Simultaneously, the pit’s 30–40 °C daytime heat accelerates moisture loss, while the 15–20 °C nights allow gradual re‑equilibration, preventing rapid spoilage. The salt also slightly lowers pH from ~5.6 to ~5.2, further inhibiting mesophilic bacterial growth.
The Science
Primary Reaction
Osmotic dehydration and salt‑induced protein denaturation reduce water activity and inhibit microbial growth