At one time just the sound of the name Camille could start people coughing, recalling the tragic Lady of the Camellias, the heroine played by Greta Garbo in the vintage film based on a Dumas story, but that image has faded, replaced by a sleek, chic, highly attractive one.
The expiration date stamped on the baking soda box in the Ochef test kitchen is three years off. We assume that means if you opened the box for the first time 35 months from now, it would still be good.
Shelf-life: Homemade rinses like this don't have any of the preservatives you'll find in store bought rinses and the baking soda in the rebalancing rinse is converted to sodium carbonate after a few days at room temperature. Sodium carbonate is still alkaline, but baking soda is a bit more gentle of an ingredient.