Kangina

'treasure', Dari pronunciation: [kʌn'ɡiːnɜ])[1][2] is the traditional Afghan technique of preserving fresh fruit, particularly grapes, in airtight discs (also called kangina) formed from mud and straw.

The centuries-old technique is indigenous to Afghanistan's rural center and north, where remote communities that cannot import fresh fruit eat kangina-preserved fresh grapes throughout the winter, and merchants use kangina to safely store and transport grapes for sale at market.

[2] Grapes preserved using kangina in modern Afghanistan are typically of the thick-skinned Taifi or Kishmishi varieties,[1] which are harvested later in the season and remain fresh in the mud vessels for up to six months.

[3] The method, a form of passive controlled-atmosphere storage, works by sealing fruit in the clay-rich mud, restricting flow of air, moisture and microbes, much as a plastic bag would.

[4] The practice of storing grapes in mud and straw has been recorded as far back as the 12th century: in his Book of Agriculture, Sevillan agronomist Ibn al-'Awwam noted layering grapes with straw in mud-sealed glass containers or "cowpat bowls" as an extant technique of preservation in Andalusia.