What is this grassy crap in the spinach?

January 17, 2012 3:51 PM

Has anyone else noticed that in loose-leaf packages of spinach from the store there's often a few leaves of a grass-like green in with them? What are they, and why do they go bad so fast?

I have done a little farm work and grown some veggies myself and I still have no idea what this might be. I was thinking it might be a kind of young spinach leaf, as the feel of the green is about the same, but that doesn't seem right based on what I have seen growing. Then I thought maybe it was a complementary green they plant along with the spinach for pest control or shade or nitrogen-fixing or something, but I dunno.

All I know is these annoying little leaves are *always* the first thing in the bag of spinach to go bad and slimy, and then they seem to take the rest of the bag with them. I sort of wish I could convince food growers not to include them, whatever they are.

posted by gusandrews to home & garden (7 answers total)

It's a spinach cotyledon leaf (the first pair of leaves that emerge from a seed).
posted by purpleclover at 3:57 PM on January 17, 2012 [4 favorites]

Man, I am so glad someone asked this, and I am so glad purpleclover answered! Not that any more evidence is needed, but the fact that those leaves exist in spinach bags in the US and Australia does support the hypothesis they're cotyledon leaves.

So do they rot first because they're the oldest leaves, or because of some property they have that mature spinach doesn't?
posted by gingerest at 4:01 PM on January 17, 2012

Huh. Great link, purpleclover. I'm willing to buy that it's a cot leaf, even though I haven't seen those leaves get beyond looking like alfalfa sprouts (I haven't had much success with my spinach...). I do wish I knew why they got so grody so fast.
posted by gusandrews at 4:08 PM on January 17, 2012

Purpleclover has the right answer. I can't remember where I read this from (it was on a different site), but if you want to prevent the spring mix from getting gross then take out these spinach leaves and separate them from the rest of the leaves. Eat the spinach cotyledon leaves first and that way you can make sure the mix lasts longer without getting all gross and slimy!
posted by livinglearning at 4:11 PM on January 17, 2012 [2 favorites]

gingerest: "So do they rot first because they're the oldest leaves, or because of some property they have that mature spinach doesn't?"

The latter(ish). A real plant biologist should feel free to step in and correct me, but essentially the cotyledon acts as a food reserve and photosynthetic kick-start during sprouting and leaf development. Once the real leaves have developed, the cotyledon is "programmed" to die off fairly quickly.
posted by Pinback at 4:33 PM on January 17, 2012

The older a leaf is on a plant, the larger a load of endophytes (fungi and bacteria that cause no outward disease symptoms) it contains. Since cotyledons fall off most plants when they are pretty young, you could avoid getting them in your spinach bag by not buying "baby spinach," and going for the mature leaves. But there'd still be older leaves in that bag, you just wouldn't be able to identify them as easily. So to preserve your spinach the longest: pick out the cotyledons, wash the spinach, and store it in the crisper drawer.

Sources: five years in grad school studying the genetics of plant-endophyte symbiosis, please don't make me look up references I'll get flashbacks
posted by emyd at 4:38 PM on January 17, 2012 [10 favorites]

Great question! I have said for a long time that those leaves are put in the spinach specifically to make it rot faster so you'll have to buy more spinach. It's a great green conspiracy.
posted by looli at 7:00 PM on January 17, 2012 [1 favorite]