butterfly bait lifetime extension/ quickly ripening bananas?

[joniverson]

I live in an area of the US where I have only recently started using my standard butterfly traps. However, the weather has been hit and miss for butterflies. I find from the past that they would frequent the traps most often when the temps are in the 80's or 90's and very humid. That has not been the case lately. My question concerns the banana mash. The mash I use is mostly Nigel Venter's recipe, which is mainly banana, sugar and a bit of yeast. How can I extend the bait's life after making? Nigel says that such bait has a normal lifetime of like 5-7 days when used at room temperature and above, but it may be close to that before I get decent weather once again, and I've already made a couple of batches. Can I refrigerate it to extend lifetime? What about freezing?

On a separate issue, is there any way to rapidly ripen bananas other than the paper bag and warm temperature tricks? I recently tried an experiment that failed. The local supermarket here (Walmart) keeps only well green bananas in stock. In the past, I've asked them about possibly obtaining over-ripened ones and my request was refused. So, I usually place about 4-5 in the bag and try to expose to as warm of temps as I can. Even so, it usually takes at least 2 weeks, sometimes even more! I read online that a banana can be quickly riped by placing in the oven at 250-300 F until the skin turns black. I tried it and it seemed to work... until I tried using it in the bait recipe. No matter how long I let the bait sit and in the sun, etc, it wouldn't ripen any further. My guess is that I must have "sterilized" banana ripening this way. Any thoughts on this would be welcome also.

Thank you in advance.