Kangina

Kangina is a centuries-old Afghan technique of preserving fresh grapes in airtight discs made from mud and straw, functioning as passive controlled-atmosphere storage that restricts airflow, moisture, and microbes to keep grapes fresh for up to six months. The method, recorded as far back as the 12th century by Sevillan agronomist Ibn al-'Awwam, is still used in rural Afghanistan for winter consumption and market transport. A 2023 study found kangina comparable to polystyrene foam boxes in effectiveness, though the containers are heavy and moisture-absorbent.