Sunlight and wort?

My brewing area outside is partially shaded until maybe 9:30 am.  Do I need to make sure I’m finished brewing  before the sun gets closer to overhead?

Will direct sun during a 60 or 90 minute boil skunk the wort and carry over into the fermented beer?  Also because my immersion chiller sticks up higher than the rim of the boil pot, I can’t completely cover it.

Thanks in advance for your advice.

Ray Daniels wrote an article about this a few years ago.  What I remember without searching for it is that in order for skunking to occur an enzyme has to be present which only happens after fermentation.

Jeff is correct. It takes isomorized AA, sunlight and riboflavin from the fermentation for the reaction to occur.

Does only UV light affect this?

I asked a similar question and was told in my Brewing Chemistry class at Central Washington Univ. that the whole light spectrum will skunk beer.

There is a hop product that is engineered to not go skunky.  Think Miller or Corona in the clear bottles.  To my knowledge it is not available to the homebrew market.

More info…

https://byo.com/mead/item/2263-lightstrike-advanced-brewing

http://articles.chicagotribune.com/2004-03-10/entertainment/0403100092_1_skunky-bottled-beer-brown-bottles

http://hopsteiner.com/wp-content/uploads/2014/03/wm-use_downstram.pdf