Ever pulled out a green-edged crisp and disregarded it without thinking, simply due to its off-putting look? One woman who did stop and ponder the reasoning behind the undesirable colour took to Facebook to share a snap in the Dull Women's Club. Perplexed by her crisp, she asked the group's 1.3 million members: "As a dull woman, I have this question - why is the edge of the chip green?" While many were quick to state the obvious - of course part of the potato it came from was green - others took the time to offer a more scientific explanation.

"The potato it was cut from was exposed to too much light or sun causing chlorophyll to develop in parts of the potato that were above ground," another Facebook user explained. While someone else detailed: "Potatoes exposed to light will produce chlorophyll (just like the leaves). Usually the tubers are under the ground and it doesn't happen, but if a potato grows too close to the surface or is stored in sunlight it'll turn green.

" A botanist couldn't but get in on the act too, meanwhile, keen to add detail from a horticultural perspective. She said: "Botanist here. Potatoes are underground stems - not roots.

If they get too close to the surface of the soil, the chlorophyll (the green pigment) develops because of the sunlight, just like in a leaf. "Not harmful to eat and the potato was not unhealthy in any way. It was just doing potato things like it should and then suddenly became a chip.

" A fourth person, however, moaned the manufactu.