The idea for this topic came to me while reading another thread. One of the big challenges with Jacks is that they come in such large packages. As has been pointed out, it can be hard to eat that much fruit before it goes bad. Here is what has worked for me:
1). Clean the jackfruit
2). Freeze the jackfruit in quantities you can eat before it spoils
3). Thaw and enjoy
Remarkably, I have noticed very little change in texture with frozen and thawed jackfruit, but I have not kept it for long periods of time. Please feel free to comment and add other ideas or thoughts.