Description
Dehydration, freeze‑drying, and pickling reduce water activity or lower pH to inhibit microbial growth in vegetables.
Technical
Dehydration removes water through heat, lowering a_w to ≤0.6 and preventing bacterial and fungal metabolism. Freeze‑drying sub‑freezes and sublimates water at –40 °C, achieving a_w < 0.1 while preserving volatile flavor compounds. Pickling acidifies the product (pH ≈ 2.8–3.5) and, when combined with high salt or sugar, creates osmotic stress that suppresses spoilage microbes.
Science
Primary Reaction
Water activity reduction and acidification
Sensory Profile
Origin & History
Civilization
Ancient civilizations
Era
Ancient to modern
Region
Global