I shocked my Korean friends when I told them we have oak and mulberry trees on our property and the acorns and mulberries mostly just rot on the ground because nobody eats acorns and the only people who eat mulberries are the kids who go out in the summer and gets sweaty and all stained pink and purple while picking and eating mulberries.
They shocked me by telling me they eat acorn jelly and dried mulberries are a popular and expensive treat.
I did try gathering and drying mulberries a few years ago- or rather, I had the kids gather, and I dried. I also have used the mulberries in muffins, but collecting enough to feed us was an awful lot of work, especially when the mulberries do not have nearly as much flavour as the other berries widely available to me at home
Here’s how to make the acorn meal: https://www.geniuskitchen.com/recipe/acorn-meal-267533#activity-feed
Here’s how to make the acorn jelly using storebought acorn meal powder/jelly powder: https://www.maangchi.com/recipe/dotorimuk-muchim
Here are some other recipes for the dotorimuk muchim: http://aeriskitchen.com/2013/10/acorn-jelly/http://aeriskitchen.com/2013/10/acron-jelly-muchim/https://www.seriouseats.com/2008/04/grocery-ninja-eating-acorn-jelly-the-unorthodox-way.html
I guess you can make a white or clear jelly using a bean powder: http://drbenkim.com/how-make-korean-jello.htm
My friend asked me what recipes I used with mulberries and I had to tell her I don’t really cook the mulberries. The kids just eat them out of hand, and occasionally I put them in muffins.