humectant

noun

1. Any substance that promotes the retention of water, especially one used to keep a food product moist.

   “[…] that you have induced a horrid phlegmatic condition with will soon require a liberal and generous humectant to keep the very membranes of your very entrails from desquamating, chipping off and blocking up all the pipes of your body.”

   “The humectant is preferably added at this stage, subsequent to centrifuging, because it increases the viscosity of the slurry. The centrifuged material with the combined humectant is then dried to remove all or most of the water.”

   “Sorbitol is an excellent humectant and is used to extend the shelf life of many baked goods and fillings.”