Propolis Propolis Propolis or bee glue is a resinous mixture that honey bees produce by mixing saliva and beeswax with exudate gathered from tree buds, sap flows, or other botanical sources. It is used as a sealant for unwanted open spaces in the hive. Propolis is used for small gaps (approximately or less), while larger spaces are usually filled with beeswax. Its color varies depending on its botanical source, with dark brown as the most common. Propolis is sticky at and above , while at lower temperatures, it becomes hard and brittle. While foraging, worker bees primarily harvest pollen and nectar,
Animal glue acid solution. The hides are heated, in water, to a carefully controlled temperature around 70 degrees Celsius. The 'glue liquor' is then drawn off, more water added, and the process repeated at increasing temperatures. The glue liquor is then dried and chipped into pellets. The significant disadvantages of hide glue – its thermal limitations, short open time, and vulnerability to micro-organisms – are offset by several advantages. Hide glue joints are reversible and repairable. Recently glued joints will release easily with the application of heat and steam. Hide glue sticks to itself, so the repairer can apply new hide glue