Yes, the milk keep longer with Iodine
in it. I dont use milk much, ;the little I buy, I keep for a month or even two. But just a small drop per liter, if more it may taste iodine.
Sour kraut is easy, it will keep for a long time if done the old fashion way by cooking and sterilizing everything.
The fermented cabbage is not cooked, so it is a challenge. With vinegar, sugar, salt, iodine; it fermented without me having to check the batch up every day. 2-3 days on the bathroom floor, then off to a cooler area for 10 days. Then refrigerated it.