In Afghanistan the grapes are stored for up to six months, kept fresh in airtight mud-straw containers. Afghans developed this method of food preservation, which uses mud-straw containers and is known as kangina, centuries ago in Afghanistan's rural north. Mechanism According to Associate Prof Jean Hunter of Cornell University, “From a food science perspective this would be considered passive controlled-atmosphere storage. Grapes and other fruits are composed of living cells which use oxygen and