Package of Beef Jerky. Tasty and pretty much last forever.
In-game description

Beef jerky is a food item in The Long Dark.

The design of the item is likely based on the real-life "Jack Link's" brand of beef jerky, which is rich in preservatives and like the description will probably last forever.

When stored outside, it takes 100 days for beef jerky to decay by 1%. Its extremely slow decay and high energy density make beef jerky a very valuable food item.

Food and drink
Canned Condensed milkDog foodPinnacle peachesPork and beansTomato soup
Animal meat Black bearMooseRabbitVenisonWolf
Fish Coho salmonLake whitefishRainbow troutSmallmouth bass
Plant Cat tail stalk
Miscellaneous Beef jerkyCandy barEnergy barGranola barMilitary-Grade MREPeanut butterSalty crackersTin of sardines
Water UnsafePotable
Soda OrangeGrapeSummit
Miscellaneous Herbal teaCoffeeEnergy drink