raw vs. cooked bananas
Since 2003 all bananas I've been able to get here in Ottawa Canada have been treated with systemic fungicides for banana black leaf streak, and the residues kill yeast when used the way I used to for banana bread (all the liquid supplied by bananas - 14 oz for 4 cups flour). It turned out that even bananas labelled organic had the residues because the exporting countries have no legal definition of organic.
Following on my experiments with raw potato, I tried cooking bananas first (boiling in water), and the yeast was hardly affected at all. I'm told by a chemist friend that most fungicides are deactivated by the heat of boiling, so this makes sense.
Has anyone found that their source of bananas gives no problem with yeast when used at the rate of a banana per cup of flour? If so, I'd like to see if I can buy it here. Banana bread was a Christmas tradition in my family for 50 years before this happened.