Well, you can ferment almost anything, but the question is does it make sense? Fermentation is controlled spoilage of food. You let food to rot and you try to control the process. Foods which ferment well contain sugar as bacteria will break sugar either into lactic acid and carbon dioxide (sauerkraut) or yeasts will break sugar into alcohol and carbon dioxide (wine). Potatoes, rice, grains. sauerkraut, beets, all those foods are loaded with sugar and will ferment well. Great Polish vodkas are made from rotten potatoes and believe me, you don't want to be around fermenting potatoes.
Meat ferments very well, however, better be good at it, as meat can spoil easy. It is no fun to throw away you salamis after playing with them for 2 months. Talking about meats, you don't ferment them with brine, you use salt and sodium nitrite and in some extreme cases salt only. All said, it makes a lot of sense to try to ferment different foods in one gallon containers. If experiment goes bad, you can always drink some of a freshly fermented wine. It is a pity that in the US we cannot distill alcohol which is allowed in most European countries. Check some of the equipment we were using in Poland. We made better stuff that was available in stores.