In Life of Pi, there are two separate accounts of what happens on the lifeboat: in one, Pi is alone with animals from the zoo, including the orangutan, Orange Juice. In the other, Pi is on the boat with his mother, a sailor, and the ship's cook. The first story is a symbolic retelling of the second—animals in the first story are representations of people in the second.
In this way, Orange Juice in the first story is meant to represent Pi's mother in the second. In the first story, Orange Juice is a comforting presence to Pi, although it is clear the animal is in shock over its status in the lifeboat. Even though orangutans and hyenas never interact in nature, Orange Juice intuits that the hyena is a predator. To Pi's surprise, the orangutan defends itself against the hyena, but ultimately she is decapitated. In the second story, Pi is surprised by his mother's anger at the cook, who, like the hyena, is also a predator. Like Orange Juice, his mother fights the cook, who beheads her.
Pi's association of his mother with Orange Juice reveals certain attitudes about his mother. Orange Juice, like his mother, is out of place on the boat but, also like his mother, surprises him in her determination to defend herself and protect Pi.