Right-clicking an Enlarged Bear Heart and selecting "Drain" will give you 1 liters of Blood of Bear. An empty Vessel, or one already containing Blood of Bear must be in your Inventory when Draining a Enlarged Bear Heart, otherwise the Blood will be lost. Blood of Bear can be stored in a Vessel or Wet Goods Container.
When poured into a Drinking Vessel and equipped to the left Hand slot, Blood of Bear can be Sipped to recover ???% of your max Blood. Each Sip will add 10 to the Quaffed & Quenched debuff.