Hi Trap,
any plant grown inside will suffer sunburn when moved outside
and some stress from the much greater transpiration of water
out of their leaves. Nothing odd about it at all. If you spend
most of your time inside, like over winter, your skin will be a lot
more likely to burn from even a little time spent in the sun.
Take the plants out on overcast days. 1) they tend to be more
humid 2) the sun, which is behind the clouds, will do less damage.
When the sun starts coming though, move the plants in to the shade
so they get only morning and evening sun which is weak. After
a week or so they will be ready for more light.
D