I figured out quite by accident that you can make your own potato starch which can be substituted where you would normally use cornstarch. I checked what I did online and sure enough, I did it right. I didn't even mean to. I just found the starch after grating potatoes and decided to try drying it.
Feel free to reply to this thread and include techniques and recipes for things you can make at home, but most people buySo here's what to do:
Potato StarchGrate potatoes (use later for hash browns or tater tots)
Scrape everything (potatoes and any liquid) into a bowl of cold water. Be sure to scrape ALL milky water off of plate or out of processor or whatever you used to grate the potatoes. That milky stuff is the starch!
Place a colander inside of a bigger bowl and line colander with cheese cloth doubled over.
Pour potatoes and water into colander
Gather up corners of cheese cloth and squeeze out the water. Transfer this water to another bowl and place colander back. Place potatoes back into original bowl and cover with more cold water. Lay cheesecloth back in colander. Dump back into cheesecloth and squeeze. Transfer that water to the bowl with the first batch of water. Repeat until water is pretty clear when squeezed out of cheesecloth. Basically you're just rinsing the potatoes over and over.
Now, put your potatoes into some cold water and a dash of lemon juice and set aside (in fridge if you're not using them right now)
By now, your potato rinsed water should have a bunch of white sediment. This is the starch. Carefully pour off the water and gather the white sludge from the bottom of the bowl. Using a scraper, spread it either onto a fruit leather tray for a dehydrator if you have one or spread it on some parchment on a cookie sheet.
If you plan to use a dehydrator, put it on low 105F to 115F for about an hour.
For the cookie sheet, I put it in my oven on low (200F on my oven) and it took about 10 minutes to fully dry. I scraped it off and put it in a jar. You can run it through any type of processor to get it really fine and powdery. I used my little electric coffee grinder. A magic bullet would work well too. I'm sure you can use it unprocessed as well.