Remediating sealing mud in Baijiu production by an innovative micro-nano bubble method

Sealing mud is essential for brewing Maotai-flavor Baijiu, which has an annual output value exceeding 20 billion dollars. However, this rare loam deteriorates after use, making soil remediation a challenge due to strict prohibition against chemical additives for food safety. Discarding soil continuously leads to environmental pollution and its eventual depletion. In response, we developed a micro-nano bubble remediation method (MBRM) for its remediation, increasing its porosity from 26.2% to 33.5%, nearly matching its original state. Furthermore, we reduced ammonium nitrogen levels by 40% and eliminated most off-flavor compounds, including butyric acid. The cosine similarity between the remediated and original sealing mud reached a maximum of 94.7%. This improvement is attributed to the dominance of aerobic bacteria after remediation, which significantly boosts their metabolic activities.