Hi I am doing a research project on banana ripeness and cannot find a way to tell the ripeness of a banana from the inside of it. I cannot use taste to measure the ripeness but I would really like to have a chart of some kind and if possible a url where you found the chart. Thank you!
Ripe bananas are softer and sweeter. You can pretty easily tell how ripe a banana is simply by biting or cutting into it, or even poking it with a finger. Ripe bananas are also more prone to bruising, which is visible on the inside of the banana as well.
If you really want to try to measure, you could indeed try to measure the sugar content. As bananas ripen, they get sweeter because starch is converted into sugar, so the sugar content should indicate ripeness. You'd need a refractometer to do that, not generally an everyday household item.
I think that the best, most accurate, measure of the ripeness of a banana is the ratio of sugar to starch.
The absolute sugar levels (ratio to mass) may be misleading, as only starch is converted to sugar, and the amount of starch is variable.
If you don't need very high accuracy, you may be able to use colour as a proxy for sugar content. The banana flesh will turn darker as it becomes sweeter. I know that hospitals use a device for checking if newborns are jaundiced. It basically measure the "yellowness" of the skin. Something like that would work well here. At the very least, a digital camera and computer will give you a decent sense of relative yellowness.