Growing up, the butter in our house was always stored in the cupboard, and it seemed to keep well for days at a time at room temp. I filled a 4 oz nalgene wide mouth jar for a trip last year and it kept for a week with no problems. When we go fishing in hotter places, we bring lots of lard. It keeps well even if it 100 degrees outside, and is great for frying freshly caught fish. Olive oil is great, but very fragrant, so if there are bears that is a consideration.