It's a bit tricky to call them "accessory organs," as they are essential for digestion. However, here are the five organs often considered accessory organs of the gastrointestinal system:

1. Salivary glands: Produce saliva, which moistens food, starts the breakdown of carbohydrates with enzymes, and helps with swallowing.

2. Liver: Produces bile, which aids in fat digestion and absorption. It also filters blood, stores glycogen, and plays a role in metabolism.

3. Gallbladder: Stores and concentrates bile produced by the liver, releasing it into the small intestine when needed.

4. Pancreas: Produces digestive enzymes that break down carbohydrates, proteins, and fats in the small intestine. It also secretes insulin and glucagon, which regulate blood sugar levels.

5. Teeth: These are not technically organs, but they play a crucial role in mechanical digestion, breaking down food into smaller particles for easier swallowing and further digestion.

Therefore, while not strictly "accessory" to the digestive tract, these five organs are vital to its proper functioning.