I am in Portland, OR.
We have a stand of summer-bearing red raspberries- not sure of variety as they came with our house. Last year, they produced loads of tasty fruit.
This year, they are again covered with fruit, but I have noticed that many of the berries taste bad. They have a musty, sour, somewhat metallic taste. Other berries from the same stand taste fine. No sprays of any kind have been used on the berries or nearby. The berries and plants look entirely normal- no signs of mold, mildew or disease. The berries are not mushy, dwarfed or deformed. They look just like the berries that taste fine. Unfortunately, the only way to find the bad-tasting berries is to taste them!
I researched every raspberry disease I could find but didn't find mention of any that caused bad-tasting berries.
Any ideas of what might be going on here?