How long can homegrown sprouts be eaten?

I have found that they get bitter after they start to sprout that far... I think you shouldn't eat them, just in case... I don't think they become toxic or anything, but they might be a little harder to digest once they mature (I am not sure about this fact, that's speculation only!)

And yes, you might get some mung bean plants, though you might want to transfer them from a sprouter into actual soil if you want to grow mung beans, and a handful of plants won't give you much yield... I had a kidney bean plant when I was a pre-teen for a school project, it produced a few dozen beans at most throughout the course of a single year... and then it froze and died...

Each type of sprout has it's own unique grow time. Mung beans are suggested to sprout between 3-5 days; the longer you sprout, the stronger the flavor and the larger the sprout. It comes down to preference, really. I like to grow most of my sprouts for the longest time possible so that they are large and have leaves. I like that I get more if I wait longer, even though it changes the taste. Unless you see mold or other problems, just grab a pinch of your sprouts each day and take a taste. If you like the flavor, regardless of how long they have been sprouting, then they are done!