Sending your cat to catch Hell-Rats yields between 1 to 4 doses of any of the spice colours. The Hell-Rat Behemoth in the southern room always drop 4 doses of the spice they guard. Spices of the same colour can be used on each other to combine up to 4 doses to save space. Once all doses are used it becomes an empty spice shaker.
The locations of the coloured spices the Behemoths guard.
Comparison to guaranteed stat boosts
A single dose of brown spice in a stew causes the affected stats to increase or decrease by a maximum of 1. Two doses affect those stats by -3 or +3, and three doses bring the maximum up to -5 or +5. Because of the uncertainty of the boost, players may prefer boosts that give a guaranteed boost every usage. The following table displays guaranteed boosts that let you complete actions above your current level: