Safety stock is the cushion above expected demand that protects you when a customer orders more than usual or a supplier delivers late. Too little and you short orders; too much and, for perishables, you write product off.
For perishable food, safety stock has a shelf life. A buffer that covers a two-week delay is no use for an item that expires in five days, so perishable buffers are usually smaller and rely more on reliable suppliers and frequent orders.
Forecast ranges help size safety stock: a wide range around expected demand means more uncertainty and a case for a larger buffer.