Has this happened to your lemons or other citrus you have taken home or picked from your tree? Did you wonder (after thinking…ick! ) what is this powdery white, blue-green stuff, and why does it so quickly turn a perfectly nice lemon into a gooey moldy mess?
A few months ago, we posted about the difference between the terms biodegradable and compostable (view post here).
In nature, mold helps food and other materials rot and is part of the composting process. Mold is a recycler, since the rotten items return back to our soil and provides nutrients for other living things.
Because lemons have thick rinds that have aromatic oils, it can usually stop most types of mold…except that is, for the penicillium digitatum –— a type of bluish-green mold that specializes in citrus.
After about a week outdoors (in Central California coastal weather) the lemon looked like this… sort of mummified. Indoors with warmer temperatures, the lemons can sometimes collapses into a gooey mess, and much quicker.
Penicillium types of mold are common and usually not harmful to healthy people — it is one of most common causes of spoiling fruits and vegetables, and what makes blue cheese.
If you find one of your citrus fruits infected with mold, it is best to remove it (very carefully) from your lemon bowl as the spores can be easily dispersed and then infect the other lemons!
Native Leaf Blog Post – Difference between the terms biodegradable and compostable
How to Put Moldy Food in Compost – from SFgate.com
The Best Way to Keep Lemons Fresh – from the TheKitchn.com
Video below from Cornell Plant Pathology Lab shows a (36 seconds long) 12 day time-lapse movie of a lemon being devoured by the fungus Penicillium digitatum.
P. digitatum causes green mold, a common post harvest disease of citrus. This is the fungus you find in your fruit bowl… as you go to grab that juicy looking orange, your finger sinks into the soft rotten flesh not knowing Penicillium beat you to it. Images were taken at 15-minute intervals.