Light Strike: Why Wine and Sunlight Don’t Mix

Written by Holly Borntrager

Unless you want its fruity and floral aromas to become those of cooked cabbage, wet cardboard, and wet dog, make sure your wine and sunlight stay far away from each other. Keep reading for more on this and what else you can do to protect your wine.


How sunlight and light strike affects wine

Does Sunlight Effect Wine?

Did you know that direct sunlight exposure can change a wonderful bottle of wine to nasty swill? This unfortunate phenomenon is light strike.

Light strike occurs when the sun’s ultraviolet (UV) rays flood the bottle. This excites the wine’s naturally occurring riboflavin (Vitamin B2) and pantothenic acid (Vitamin B5).

These energized molecules then react with naturally present amino acids. This yields sulfur-containing compounds that we can smell at very low levels, and they stink!

3 hours of sun exposure is all it takes for wine damage to occur in clear bottles. Wine in green bottles takes only 18 hours. Be mindful of where a store has placed its wine before purchasing.

Choose a wine that is not near a window or exposed to the sun.

But is there another solution for fighting off those UV rays?


uv-light-wine-bottle-color-damage-illustration-winefolly
The color of the bottle greatly affects UV exposure.

Bulbs & Bottles: More Wine-Saving Methods

Who would have thought that the color of the bottle makes such a difference?

As proof, a study showed that amber glass, not the winemaker’s usual choice, offers near TOTAL protection from UV rays. Green glass offers moderate protection, and clear glass very little.

Historically, green glass was the easiest to produce in large quantities. It predates any understanding of light strike, thus making it the most common today. Clear glass is a newer choice that offers practically no protection.

This is a real shame, as most of us like to see the beautiful shades of white, yellow, green, and rose within.

Expensive bottles of wine being stored in direct sunlight.
Storing expensive bottles under fluorescent lights can cause light strike too. Be wary of bottles displayed under non-LED lighting.

Lastly, if you want to get technical and put a stop to UV damage altogether, install LED bulbs. This is a great solution, as they do not emit any UV rays.


It’s Not Impossible!

Keeping wine and sunlight separate might seem tough. But as we’ve seen, there are tons of methods for keeping your wine delicious and sun-free!

Protecting your wine from UV rays, considering the bottle’s color, and even installing LED bulbs will prolong the life and flavor of your wine.

Do you have any tried and true methods for keeping UV rays away from your wine? Let us know!

Written byHolly Borntrager

Sharing hospitality, good food and wine is my passion. Performing complex, scientific analyses is my career. Combining them, I possess a unique perspective and desire to contribute.