I realized yesterday that I didn’t have the cornstarch a recipe called for. I texted my father in law and he brought over a container. The expiration date in a year out. He didn’t buy it and his wife has been deceased for almost 3 years. She was sick and not cooking for the year prior to that. So, this stuff must be good for at least 4-5 years. What products have a longer shelf life than that? I thought 4 years or more was pretty extreme.