kangina

thumb|upright=1.15|A paper-lined , opened to access the grapes stored inside (Dari: , ), also called , is the traditional Afghan technique of preserving fresh fruit, particularly grapes, in airtight discs 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 -preserved fresh grapes throughout the winter, and merchants use to safely store and transport grapes for sale at market. Grapes preserved using in modern Afghanistan are typically of the thick-skinned or varieties, which are harvested later in the season and remain fresh in the mud vessels for up to six months.

thumb|Video of a being opened 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. Discs are formed from two bowl-shaped pieces, which are sculpted from mud and straw, and baked in the sun before being filled with up to of un-bruised fruit and sealed with more mud. They are kept dry and cool, away from direct sunlight. Gradual permeation of gas through the clay barrier allows oxygen to enter the container, keeping the grapes alive, while the elevated concentration of carbon dioxide inside the package inhibits the grapes' metabolism and prevents the growth of fungus. The grapes are prevented from drying out, and the mud absorbs liquid which would otherwise lead to bacterial and fungal growth.